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Safety

    When Should You Upsize Your Canopy?

    At the end of the day, skydiving is a dangerous sport. I’ve lost many friends and even family members– under properly functioning parachutes. We can’t regulate stupid behavior, but we can at least spread good information so more people can make wise decision.
    So why would someone consider upsizing?
    10. Cannot land consistently standing up. If you’re having troubles standing up consistently or even in the same area in all weather conditions, then you need to upsize and take a canopy course to understand the concepts basic flight characteristics.
    9. Not current. You can be uncurrent after a winter vacation without skydiving, coming off an injury or just life getting in the way. According to USPA, you are uncurrent if:
    A-license holders who have not jumped within 60 days
    B-license holders who have not made a freefall skydive within the preceding 90 days C- and D-license holders who have not made a freefall skydive within the preceding six months
    DZ policy: Every DZ has their own policy for uncurrent skydivers. Be sure to check in with them before coming out to the DZ to see what you may have to do. Also check the USPA Skydiver’s Information Manual for more info. 8. Jumping at a Higher Elevation. At higher elevations the canopy is going to perform faster and act more responsive because of the air being less dense. So landings will feel faster and turns will feel more aggressive. If you’re traveling to places like Colorado or Utah, you may want to pack a larger canopy.
    7. Gained Weight/Wearing Weight. Well, what can I say? Sometimes during the winter, it’s easy to pack on some pounds and that invariably negotiates your wingloading. Also, if you haven’t jumped all winter and you’ve accumulated a new wingloading, you may want to consider getting current on a bigger canopy.
    Next, if you’re a small girl, or decide to get on a 4-way team, you may be wearing weights. This added weight will definitely make your canopy fly differently than expected. So before making a decision on what canopy to buy or whether or not to downsize, consider the use of weights to make the best wingloading decision for your experience.
    6. Reserve Size. Generally, your main and reserve should be about the same size. If you were quick to downsize or couldn’t find the right sized container, but have a larger reserve, with little experience under a bigger canopy, may be a good reason to upsize your main. (Having the same sized canopies also reduces other problems should 2 canopies out occur.)
    5. Types of Jumps. Doing big ways? Wingsuiting? Demos? Some jumps may warrant a bigger parachute. When I do world record jumps, I usually opt for my bigger canopy so I’m not fighting my way through traffic and have a larger range of floating. Wingsuiting can cause line twists or other malfunctions and jumping a more docile canopy can help you negotiate them better. On demos, having a lower wingloading will give you more range to negotiate smaller landing areas or areas surrounded by obstacles – as long as you understand the flight dyamics of your wing.
    4. Age/Health/Agility. Take an inventory of your overall health. How are your knees? Wrists? Ankles? Eyesight? Depth perception? Reaction Time? These may be considerations to upsize.
    3. Attitude/Experience. Someone’s overall experience and attitude about the safety of themselves and others is a vital component in skydiving safety. Disregard for your own experience and/or safety is an obvious sign to upsize.
    2. Because You Downsized and You Shouldn’t Have. Having inconsistent landings? Not standing up your landings? Stabbing out your flare? Landing by touching down on your knees first then popping up to your feet thinking it was an awesome swoop? Spiraling in traffic cause it’s freakin’ fun on a small canopy when not necessary? Scared of line twists? Having a hard time kicking out of line twists? Not paying attention to others in the sky? Land downwind for fun? Don’t follow a landing pattern? What the hell is a landing pattern? Don’t understand the flight characteristics of your wing? Pretty much don’t follow the rules?
    1. Finally, if you cannot answer yes to all of these questions, you need to upsize:

    Can you land your main crosswind?
    Are you comfortable landing crosswind?
    Can you land your main downwind?
    Are you comfortable landing downwind?
    If you had to land out and the only option was a tight area surrounded by obstacles, do you know you could land your canopy accurately?
    Do you feel that you completely understand the flight characteristics of your wing?
    Do you understand what happens to the flare, landing pattern, stall characteristics and overall flight characteristics when you downsize?
    Have you used your rear risers & do you know why and when you’d need to use them?
    Have you used your front risers & do you know why and when you’d need to use them?
    Have you performed braked turns? Braked turns for landing?
    Can you land within 10 meters of a target center at least 5 times in a row?
    Did you take a canopy course beyond the B-license requirements? When I first started skydiving, I was young and pretty much invincible. I was on the fast track to get on a small canopy and go fast! And it’s all fun, until you get hurt or you watch someone die. I’d seen a lot of crazy things (especially people “getting away” with bad decisions) in my 20-year career, but in 2003, I witnessed my father’s fatal canopy collision. Then without your permission, things change.
    It’s amazing how death will completely transform your perspective on safety, especially when the sport is your livelihood.
    We spend more time under canopy than we do in freefall, so this is a moment to check in and evaluate how much canopy education have you gotten? My dad used to tell me, “take stock into your destiny.” So, take that Flight 1 course you’ve always wanted to, finish your B-license canopy training, ask questions, and just know, there ain’t no shame to upsize that thang!
    How at risk are you?
    Below is a canopy risk calculator that was created by the USPA, which can give you an idea of just how big of a safety risk you're at with your current canopy and experience level
    Calculate My Canopy Risk Useful Resources

    Barry Williams on Canopy Safety (Skydive Elsinore 2013 Safety Day) [Video]

    Barry Williams on Canopy & DZ Safety (Skydive Elsinore 2012 Safety Day) [Video]
    Performance Design's "Survival Skills for Canopy Control"
    Contributors: Melissa Lowe, Barry Williams and Jason Moledzki

    By admin, in Safety,

    Parachute Malfunctions

    A malfunction is any failure of the system to provide a normal rate of descent and this includes loss of canopy control. Malfunctions are normally caused by one or a combination of the following: bad packing, poor body position during canopy deployment and/or faulty equipment. There are some malfunctions, however, that just happen (Acts of God); parachutes are good but not perfect. Failures of the main parachute can be divided into two areas. Either nothing comes out and you have a total malfunction or the canopy starts to open but something is wrong with it and you have a partial malfunction. Each of these two areas will be broken down still further in this chapter.
    It is because of the possibility of an equipment malfunction that the USPA’s Basic Safety Requirements list the opening altitude for students at 3,000 feet AGL. (For tandem jumps, it is set at 4,000 feet AGL. For A and B licensed skydivers, it is set at 2500 feet.) The BSRs and the FARs require that a second (reserve) parachute be worn for all sport jumping. It is important that you are drilled in its use. But even with the stated opening altitude safety margin or cushion, you must be aware of the time, speed and distances involved. If you exit the aircraft at 3,000 feet AGL, for example, you will begin to accelerate; you start off at zero vertical speed and then fall faster and faster until you reach terminal velocity (more about that later). If you didn’t have a parachute, it would take you about 22 seconds to reach the ground. In the case of a partial malfunction, you will have a little braking from your canopy and this means even more time. But even if you have a total, allowing for reaction time, you should be open under your reserve at well above 1,500 feet. In fact, while it seemed like an eternity to you, your friends on the ground will tell you that you performed your procedures quickly and efficiently; you will be surprised at how fast you react to a malfunction. Your main parachute takes 3-4 seconds to open and the reserve may be just slightly faster. Even at terminal velocity, which in a face-to-earth,stable position is about 110 mph, (the fastest you can fall in that position), four seconds translates into about 700 feet.
    If you haven’t been jerked upright by the sixth segment (second) of your exit or pull count, you should already be into the emergency procedure for a total malfunction. Static lines not hooked up, in-tow situations, lost or hard ripcord pull or pilot chute problems have already been discussed and won’t be repeated here.
    Total Malfunctions
    Of all the possible equipment malfunctions, the total (pack closure) is the safest to deal with because there is no other garbage over your head to interfere with the deploying reserve. While the total is the easiest malfunction to rectify, remember it also presents you with the least amount of time in which to act. Do not spend time trying to locate a lost handle; you do not have time. Do not waste time breaking away; a loose riser could tangle with a deploying reserve. When in doubt, whip it out. (Pull the reserve ripcord.)
    Partial Malfunctions
    A partial malfunction is one in which the canopy comes out of the container but does not properly deploy. The canopy may not inflate (e.g. a streamer that hardly slows your descent at all) or it may take on some air and be spinning violently (e.g. a line over or slider hang-up). You could have an end cell closure that will probably slow you enough for a safe landing. So, partial malfunctions may be major and minor. An additionally important consideration is that they may be stable or spinning. Most partials can usually be attributed to an error in packing or poor body position on opening. Some partials, however, just happen.
    Some partials are so minor, most instructors do not even classify them as malfunctions; they call them "nuisances." Some of these things that just happen are line twists, end cell closures and a slider that has not fully descended. These are correctable problems which you will be trained to handle.
    A good canopy is rectangular (square) and flies straight once the slider is down and the brakes are released. It is stable through the flare and turns properly with the correct toggle inputs. (Remember the controllability check?)
    Major partial malfunctions. Ones that you don’t waste time to correct.
    Bag lock presents you with trailing lines, bag and pilot chute but the canopy will not come out of the bag. This problem is not likely to clear itself. Breakaway and pull your reserve.
    Horseshoe. This malfunction can result from bad maintenance, failure to check equipment and incompatible canopy/container systems. It can happen when the locking pin or ripcord is dislodged from the closing loop, allowing the bagged canopy to escape before you have removed the pilot chute from its stowage pocket.
    The horseshoe can occur if you tumble during the deployment sequence, allowing the pilot chute to catch on your foot, your arm, or some other part of your body, but these are rare occurrences today. Another possibility is a poor launch of a pilot chute from your container, allowing it to fall back into your “burble” (the partial vacuum behind you) where it can dance around and snag on something, preventing it from properly deploying. Improper hand deploy procedures can lead to the pilot chute being caught on your arm.
    The danger of a horseshoe malfunction is that a pulled reserve may tangle with the horse-shoed main as it tries to deploy. If you experience a horseshoe, and you are using a hand deployment technique, pull the main’s hand deploy pilot chute immediately. Then, and even if you can’t pull the main hand deploy pilot chute, execute a breakaway and deploy the reserve. Chances are that there will be enough drag on the lines and canopy to separate the risers from their attachment points and present only a single line of “garbage” for the reserve to clear (rather than a horseshoed main).
    Violent spin. Unless you can tell immediately that you have an unstowed brake, breakaway and pull your reserve. If you have plenty of altitude and the problem is not compounded by line twists, push the toggles down to the crotch for two seconds, then let up slowly. If the spin continues, break away and pull your reserve.
    Line overs can occur when a brake lock releases during the opening sequence allowing one side of the canopy to surge forward over itself, or due to a packing error or an Act of God. If you are on a very high clear and pull, you may try to pull down on the end lines (by the risers) to make the other lines slip off. However, if you deployed at the normal pull altitude, you do not have time for this maneuver on the main. Break away and pull your reserve ripcord. If this happens on a square reserve, pulling down on the side the lines are over is your best hope, along with a great PLF.
    Partial Malfunctions That May Be Majors Or Minors
    Partial malfunctions that may be majors or minors. You may have time to make a decision as to how to handle them.
    Rips and tears are not common on ram-air canopies and may usually be ridden in. Even a rip from leading edge to trailing edge on one surface can probably be controlled. Internal rips may not be visible. See whether the canopy is controllable with toggle pressure no lower than your shoulder. If your controlability check indicates a serious problem, break away and pull your reserve ripcord. If the check does not indicate a serious problem, make slow, shallow turns and flare slowly for landing.
    The snivel is a slow, mushy opening. The canopy’s fabric weave opens up slightly after a few hundred jumps and becomes more porous. Higher permeability leads to sniveling. Look up after pulling to watch your canopy open. Learn to distinguish a slow-opening snivel from a never-opening streamer. Sometimes replacing the pilot chute will lead to quicker openings. Try packing the nose of the canopy in different positions but check with a rigger before you experiment. Contact the manufacturer about resetting the brakes two inches higher. Then the canopy will take to the air with the tail somewhat higher giving the leading edge a better bite of air.
    Slider hang-up, at the canopy. The slider may hang up at the top of the lines because it is caught in the lines or caught on the slider stops. Grommets become battered and rough as they slide down and hit the connector links at the risers. The links should be fitted with plastic sleeve buffers. Make sure the grommets are smooth. A slider hang-up at the canopy is a high-speed malfunction and will be hard to clear. You may be upright but you are descending quickly. There is little time to deal with a slider hang-up at the canopy, so jettison your main and pull your reserve ripcord.
    Slider hang-up, halfway. A slider hang-up halfway down the lines will slow you down but possibly not enough for landing. Check your altitude and if there is time (you are still above the decision altitude for emergency procedures), release the brakes and pull the toggles down to your crotch for two seconds in an effort to stall the canopy and relieve some of the spanwise spreading of the canopy. Repeat if necessary, pump the steering lines up and down. If the slider descends to within 10 or 12 inches of the connector links, that is close enough. Sometimes, the slider is caught higher in a suspension line or steering line. Let both toggles up to determine whether the canopy will fly straight. If you have to pull down the opposite toggle to more than shoulder level to maintain straight flight, the canopy will probably be unstable. If you don’t gain total control of the canopy by the decision altitude (sometimes called the hard deck), break away and pull your reserve ripcord.
    If the slider comes down the lines halfway and stops, the canopy has probably changed in some way. After you are safely on the ground, measure the line lengths and compare opposite lines. Check the slider grommets for damage. Bring the canopy to the equipment manager (if it is student gear), your rigger, or send it to the manufacturer for inspection.
    Broken suspension line(s). Most line breaks only put the canopy into a slight turn. Correct the turn with opposite toggle pressure. Occasionally the broken line causes the slider to hang up. Do a controllability check. If there is any internal damage to the canopy, it will not perform as expected. Failing a controllability check will dictate a breakaway and a reserve deployment.
    Minor Malfunctions
    Minor malfunctions are more like nuisances that can be dealt with and don’t threaten you unless they get worse or are complicated by other problems.
    Line twists. Sometimes, the bag rotates a few turns as it lifts off. Now you may find it difficult to get your head back to look up at the canopy. The problem is that the risers are closer together and twisted instead of spread. These twists can happen with or without your help. If you are kicking, rocking or twisting just as the bagged canopy lifts off, you can impart a twist to it. The principle is the same as when you give a Frisbee disc a flip of the wrist on launch. Line twists are more common on static line than freefall jumps.
    Determine quickly whether the canopy is flying straight, your altitude and which way the lines are twisted. Reach above your head, grab the risers and spread them to accelerate the untwisting. If necessary, throw your legs in the twist direction. Line twists are worse on a ram-air canopy than a round because you cannot pull down on the steering lines to control the canopy until the twists are cleared and this may take up to 30 seconds. If the canopy is spinning in the same direction, you may not be able to untwist faster than it is twisting. Do not release the brakes until untwisted. While you have the risers spread, check your canopy to make sure nothing else is wrong with it. A spinning canopy descends quickly. If you haven’t untwisted the lines by 1,800 feet AGL, break away and pull your reserve.
    Premature brake release. Ram-air canopies are packed with their brakes set to prevent the canopy from surging on opening. If one brake releases on opening, the canopy is likely to turn rapidly which can escalate into a spin and/or an end cell closure if not corrected immediately. If the canopy doesn't have line twists, grab both toggles and pull them down to your waist. (Grabbing both eliminates having to choose which one to pull.) This maneuver will release the other brake, reduce your forward speed, stop the turn and let you see if any lines are broken. If the premature brake release is compounded with line twists, releasing the other brake may have some or no effect. Be aware of your decision altitude and try to unspin from the line twists. If you are sure that just one steering line is still set in its deployment setting, you might try to release it.
    Broken steering line. When you find one of your steering lines has snapped or floated out of reach, release the other brake and steer the canopy by pulling down on the rear risers. Do not try to steer with one control line and the opposite riser. The turns will be inconsistent and you may find yourself in a dangerously low turn when you flare for landing. Pulling down on the risers may be hard but it will steer the canopy. The canopy will probably want to turn in the direction of the good control line. If you cannot make the canopy fly straight with the opposite riser, break away and pull your reserve. If the broken line wraps around the slider, do not try to pump the slider down any further. It will only make the turning worse. Reserve some energy to pull down on both risers at about ten feet from the ground to flare the landing. You want to start this flare lower because pulling down on the risers results in a more pronounced flare.
    Steering line(s) won’t release is similar to dealing with a broken steering line, except that one may release while the other won’t. If neither steering line releases, simply fly the canopy to a safe landing using the rear risers. If only one releases, then you can pull that steering line down to the point at which the canopy will fly straight, then control the direction the canopy flies by either using the rear risers or using the one working steering line. Quite often, you will have time to grab the riser of the steering line that won’t release and work towards getting it released. Be mindful of your altitude as you work on the problem. You don’t want to steer yourself to a hazardous landing while you are distracted with this release challenge.
    Pilot chute "under/over" problems. The pilot chute may fall over the leading edge of the canopy and re-inflate underneath, usually causing a turn in the distorted canopy. Attempt to stall the canopy slightly so that it backs up, possibly allowing the pilot chute to come back up and over the front of the parachute. If the canopy cannot be controlled with toggles, break away and pull your reserve ripcord.
    End cell closures occur when the pressure outside the canopy is greater than the pressure inside. They usually happen during canopy surge on opening but they can also be caused by radical turns or turbulent air. Turbulence can occur on hot, no-wind days, on windy days downwind of trees and buildings, and during stormy conditions. Lightweight jumpers under large canopies (called low wing loading) will experience end cell closure more frequently. To avoid end cell closure, fly with one-quarter to one-half brakes. To counteract end cell closure, push the toggles down to your crotch for a few seconds, until the cells inflate, then let the toggles up slowly. Repeat if necessary. End cell closures are not a major concern. Keep the canopy and land it if it is not spinning. If the end cells collapse below 200 feet, do not try to re-inflate them.Pull to half brakes to stabilize the canopy. When you flare for landing, the cells will probably pop open.
    Combination Malfunctions
    When confronted with more than one malfunction, correct for line twists first. The canopy will be uncontrollable until the twists are removed. When in doubt, whip it out, especially if you are at or below decision height (1800 feet AGL).
    Two Canopies Open

    You may find yourself confronted with two fully open canopies. This can happen in several ways: The automatic activation device on your reserve could fire when you are happily flying your canopy through 1,000 feet; you may have reacted very quickly to a pilot chute hesitation without effecting a breakaway; or the main release system may have failed to separate during an emergency procedure.
    If the two canopies take off at different times, they may not deploy into each other, but you need to be prepared to handle that possibility. At the Parachute Industry Association Symposium in Houston in 1997, a detailed report was presented on the performance of two ram-air canopies out — a very dangerous situation.
    First, quickly check the condition and position of the main and reserve canopies, then make your decision based upon the following:

    If the two canopies are flying side by side, steer yourself to a safe landing area by using gentle control inputs on the larger canopy. Due to the nearly doubled surface area supporting your weight, the effective lift of the parachute system will make flaring the canopies unnecessary. Flaring one could create a hazardous situation, especially close to the ground.
    If the two canopies are both flying downward towards the ground (called a downplane), jettison the main. Note:Certain reserve static line lanyards may have to be disconnected so as not to foul the reserve parachute when the main is disconnected. Ask your instructor about the specifics concerning your system.
    If the canopies are flying one behind the other and in the same direction (called a biplane), make gentle steering inputs with the lead canopy (which is usually the main). Do not release the rear canopy’s deployment brakes. Do not flare the landing.
    If the reserve container has opened but the reserve canopy has not yet, or not completely deployed, make gentle steering inputs with the main and try to haul in the reserve and stick it between your legs.

    Tandem Jumping Malfunctions
    Tandem jumping malfunctions may be aggravated because the weight is doubled while the effective drag area of the two falling bodies is not. As long as the drogue pilot chute has been deployed properly, freefall speeds are about the same as a single skydiver. If the drogue is not deployed or fails to work properly, the terminal velocity will be much faster than that of a single skydiver (110 mph); perhaps as much as 160-170 mph. The greater speed places a much greater strain on the parachute system and on the jumpers.
    Large Ring And Ripcord Handle
    Older harnesses used a plain round ring for the largest of the rings in the 3-Ring canopy releases. When the main canopy is jettisoned, the largest of the riser-release rings remains on the harness. If the rings flop down on the lift web, the one near the reserve handle may be mistaken for that handle. Both are large silver rings and the reserve handle may have shifted from its normal position. Some jumpers have broken away only to tug on the wrong ring. Some never lived to tell about it. Newer equipment may have a shaped large ring or a smaller (mini) ring that is more difficult to confuse with the reserve handle. If you have older equipment, you should be aware of this potential problem.
    Change Of Emergency Procedures
    Anytime you change your equipment or emergency procedures, make sure you are thoroughly trained. Practice in a suspended harness until proficient on the new equipment. Each corrective procedure is different and you must not waste precious seconds in an emergency thinking about what you should do. You must act automatically and quickly. Review your emergency procedures prior to each jump and touch all your handles before you proceed to the door.
    Breakaway Training
    Breakaway training is essential to assure that it will be accomplished completely, quickly and well. Training must take place in a suspended harness that is easy to rig up. Simply tie an old set of risers to an overhead beam and attach them to your harness. The drill must be repeated again and again until it becomes mechanical and automatic so that you will perform correctly and without hesitation should the time come. When you take your reserve in to be repacked, ask your rigger if you may practice the breakaway to include the reserve pull. It is a valuable experience and in this controlled environment, it is safe for your gear.
    Emergency Priorities
    Think about and review the seven priorities of skydiving:

    Pull - Open the parachute.

    Pull by the assigned altitude or higher - whether stable
    or not.

    Pull with stability - to improve canopy-opening reliability.

    Check the canopy - promptly determine if the canopy has
    properly opened and is controllable.

    If necessary, activate the reserve - perform the
    appropriate emergency procedures if there is any doubt that the main canopy is
    open properly and is controllable.

    Land in a clear area - a long walk back is better than
    landing in a hazardous area.

    Land safely - be prepared to
    perform a PLF with the feet and knees together to avoid injury.

    Canopy Collisions
    Let’s assume that your canopy has just opened properly and you are reaching up for the toggles when suddenly, you look ahead and see another canopy coming directly towards you. What should you do? If the collision is avoidable by steering to the right or left, choose the right. The turn to the right is virtually universal in all forms of navigation. If the collision is unavoidable, spread your arms and legs out to absorb the impact over the most surface area possible. Chances are that spreading out will allow you to bounce up and over the lines and canopy you will be colliding with. You may get a bit hurt, but you will be alive so long as you don’t make full body contact with the other jumper. If you find yourself entangled with another parachute, the general rule of thumb is that the lower person has the right to perform emergency procedures first. Communicate with each other as to what you want to do, what you’re going to do, then do it while you still have enough altitude to do it safely.
    Most canopy collisions occur during the landing phase of the skydive, when too many people are trying to get into one tiny area all at the same time. Vigilance in canopy control and choosing a less congested area can help avoid this emergency. If you do end up tangled at an altitude too low to break away (less than 500 feet AGL), ride about half brakes and get set to do a fantastic PLF.

    By admin, in Safety,

    Downsizing Checklist

    While I was an S+TA, I spent a considerable amount of time telling people they shouldn't be loading their canopies so heavily. 90% of the time it didn't work. Skydivers can have a bit of an ego, and when I told them they probably shouldn't downsize yet they heard "I think you're a crappy canopy pilot who can't handle a smaller wing." So they downsized and broke their legs, backs and pelvises with some regularity.
    A few years back I met up with Brett, one of the people I'd been lecturing to whle I was an S+TA. He told me that he wished he'd listened to me back then. He had broken his femur during a botched landing, been out of the sport for a while, and then came back and really learned to fly his canopy. He took a canopy control course and actually upsized to get more performance out of his canopy. He ended up coming in first in one of the events at the PST that year.
    That started me thinking. Maybe the approach I was taking was wrong. Since jumpers tend not to listen to other people who tell them they're not as good as they think they are, perhaps if you could give them better tools to evaluate themselves they could make better decisions about canopy choices. It's one thing to have some boring S+TA guy give you a lecture about not having any fun under canopy, quite another to try to perform a needed manuever under canopy - and fail. In that case there's no one telling you you can't fly the canopy, it's just blatantly obvious.
    So I came up with a list of canopy control skills everyone should have before downsizing. Some are survival skills - being able to flat turn would have saved half a dozen people this year alone. Some are canopy familiarization skills - being able to do a gentle front riser approach teaches you how to judge altitude and speed at low altitudes, and how to fly a parachute flying faster than its trim airspeed, a critical skill for swooping. It's important to do these BEFORE you downsize, because some manuevers are a little scary (turning at 50 feet? Yikes!) and you want to be on a larger canopy you're completely comfortable with before trying such a thing.
    The short version of the list is below. Before people downsize, they should be able to:
    flat turn 90 degrees at 50 feet
    flare turn at least 45 degrees
    land crosswind and in no wind
    land reliably within a 10 meter circle
    initiate a high performance landing with double front risers and front riser turn to landing
    land on slight uphills and downhills
    land with rear risers
    Details:


    1. Flat turn 90 degrees at 50 feet.
    This is the most important of all the skills. The objective of this manuever is to change your direction 90 degrees losing as little altitude as possible, and come out of the manuever at normal flying speed. Coming out at normal flying speed means you can instantly flare and get a normal landing. If you can do this at 50 feet, and come out of the manuever with normal flying speed at 5 feet, you can flare and land normally.
    Every year people die because they decide they simply have to turn at 100 feet and know only one way to do it - pull down a toggle. The parachute dives and they hit the ground at 40mph. To prevent this, not only do you have to know how to flat turn, but you have to practice it enough that it becomes second nature. Then when you do need it, you won't have to think about it.
    To pull off this manuever, start by toggle turning the parachute gently. IMMEDIATELY follow that with some opposite toggle. The idea is that you want to flare just a little to counteract the canopy's desire to dive. Continue adding opposite toggle until you've stopped the turn. At this point let both toggles all the way up. If you feel the parachute accelerate after you let go of the toggles (i.e. it feels like you just flared) use less opposite toggle next time. If you feel like the parachute is diving, like you just did a toggle turn, use more opposite toggle next time. Basically you want to start the turn with one toggle, stop it with the other one, and use just enough toggle to keep the wing from diving but not so much that it does a flare.
    It should go without saying that this manuever should be practiced up high before you ever try it down low. If and when you do try it out low, start at lesser angles (i.e. try a 15 degree turn first) make sure the pattern is clear and make sure conditions are good (soft ground, good winds.) Work up gradually to a full 90 degree turn. I do think it's important to try at least a gentle flat turn very low; we are horrible judges of exact altitudes when we're at 1000 feet, and it's hard to tell if you've lost 50 feet or 200 in a turn. By trying it out down low, you'll get a better sense of what it can do for you, and you'll have the "sight picture" better set in case you have to use it for real one day.
    A variation on this is to go to half brakes and then let one brake up. This gives you a flat turn, but by flaring first you "use up" some of the canopy's energy so you can't turn as effectively. On the plus side the turn happens more slowly. If you are about to hit a tree and want to make a last minute turn, this variation might be the way to go, as it combines a turn and a flare, thus reducing your speed before impact. A version of this is currently taught in the ISP, so it might be a good way to make your first flat turns before transitioning to the less-braked variety.

    2. Flare turn at least 45 degrees.
    This does two things - it gives you another tool in your arsenal to dodge last minute obstacles, and teaches you to fly your canopy all the way through to the landing. The #1 mistake jumpers with new HP canopies make is to "reach out to break their fall" while they're flaring; this of course turns the canopy in the direction they are reaching. Most people decide that this is due to a side gust just as they're landing. I remember one jumper at Brown who, amazingly enough, experienced a side gust seconds before he landed (and always from the right) 40-50 times in a row! Learning to flare turn will help eliminate this problem.
    To flare turn, start with a normal flare, then flare slightly more with one toggle. The canopy will turn. Bring the other toggle down to match it, and the canopy will straighten out. It's a dynamic process; rather than put the toggles at a certain position, you have to speed up one toggle for a second, then speed up the other to match it, before you level them and finish the flare. If you balloon upwards, then don't flare as quickly. If you drop to the ground, bring both toggles down more aggressively when they are 'split.' One thing that helps people is to think about where your canopy is rather than what it's doing. Use the toggles to put it off to one side for a moment, then use them to put it back over your head.
    This can be hard to practice with a large canopy. I can pull off a 45 degree turn on a Manta, but the flare is over so fast that it's hard to explain what I just did. It's much easier on a canopy loaded around 1:1, so you may want to wait on this one until you get to that loading.
    Note that if you combine a flare turn with a flat turn, you can pull off nearly a 180 degree turn at just above 50 feet. Also note that knowing how to do flat and flare turns doesn't mean you can always turn at 50 feet and get away with it - sometimes it's better to accept a downwind landing than make a turn at a dangerously low altitude. But if you do have to turn low (say, you're on course for the electrified fence around the pit bull farm) a flat/flare turn will let you either turn and land normally or turn and minimize the damage caused by landing in a turn.

    3. Land crosswind and in no wind.
    These are straightforward. No wind landings are pretty easy; the only issue is that your perception of speed and altitude will be off. Since you seem to be moving faster over the ground when there's no wind (which you actually are) it can seem like a good idea to add just a little brake to 'slow you down' before you land. Resist that urge! Keep that speed in your canopy; you can turn the speed into a good flare only if you start the flare with decent (i.e. full flight) speed.
    Crosswind landings can be a little more tricky because of that strong tendency to want to "reach out to break your fall." Counter this by flaring with your hands in towards the center of your body. You may have to PLF on these landings, since you'll have some decent forward speed and have some sideways motion from the wind. If you want to get fancy, try a flare turn after you start your flare on the crosswind landing - you can easily pull off a standup landing if you get turned enough before you put your feet down.
    If these work well you may want to try a downwind landing. The benefit to doing that is it will prepare you to accept a downwind landing in the future; you won't be tempted to turn too low to avoid it. Choose an ideal day for this one, with a slippery landing area (wet grass is perfect) low winds and a clear landing area. Prepare to PLF, and think about "laying it down" on your thigh as you land to start sliding. You can slide across grass at 30mph without getting hurt, but planting your feet and cartwheeling at those speeds can be very dangerous.

    4. Land reliably within a 10 meter circle.
    This is essentially the PRO requirement. This is critical because your accuracy skills are what will keep you from having to turn low. It's very comforting to know that you can land in any 50ish foot clearing if you find yourself having to land out; it's especially important as you get to smaller canopies that need longer and longer runways to land well. Your only option may be a section of road, and you may have to hit the beginning of the road dead-on to have enough room to slow down.
    The subject of canopy accuracy is too long to do justice to here, but the top 3 hints I've heard are:
    - If you're not sure if you're going to make it over a wire or tree, look at what it's doing with respect to the background. If more background is appearing from beneath the wire or tree, you're probably going to make it.
    - As you look at the ground, most points will seem to move away from a central point. Some will rise, some will fall, some will go out to the side. If you look long enough you'll find one point that's not moving - that's where you're going to land if the winds don't change all the way in (which is rare.)
    - Going into brakes usually makes you land short in high winds, but can extend your glide in no wind. Front risers almost always make you land shorter.



    5. Initiate a high performance landing with double fronts, and a front riser turn to landing.
    I am pretty convinced that front riser high performance landings are a lot safer than toggle turn high performance landings, and double fronts are the safest of all. If you do it too low, or become worried about the landing - just drop the risers and you're back to normal flight.
    For double front riser landings, set up a normal landing, aiming for a point a little farther away than you normally do. At 100 feet or so, pull down both front risers. Your canopy will drop and accelerate. At some point above the ground (30-10 feet depending on your canopy) drop the front risers. Your canopy will begin to recover. Before it completes the recovery to normal flight, you should be at flare altitude. Start the flare normally. You may need to use less toggle than normal, since the canopy is now going faster than you're used to, and the same amount of toggle gives you more lift. You will also plane out farther, since you have more speed you have to bleed off before you come to a stop.
    For front riser turns to landing, first try front riser turns out above 1000 feet and get used to how your canopy recovers. Then start by coming in 10 degrees off the windline, and making a gentle front riser turn to line up with the wind at ~100 feet. The canopy will dive and accelerate, so be prepared to drop the front riser instantly and flare if you have to. Also be prepared to steer in the flare, since the canopy may not have stopped turning completely before the flare begins. Done correctly, you'll start the flare with more forward speed, giving you a longer planeout.
    Make sure your flares are smooth for this! A smooth flare generates more lift for a longer period of time than "stabbing" the brakes. However, don't start the flare at 30 feet - starting the flare that high will slow the canopy down, negating the effects of the front riser approach. If you do find yourself stabbing the brakes to prevent hitting the ground, move the altitude at which you start front risering up.
    Probably the most critical skill you will get from this exercise is the development of the "sight picture." Below 200 feet your altimeter is pretty useless, and you should be looking at traffic and the landing area anyway. Eventually you'll develop a sense of what "picture" you should see just before you start that riser turn. The picture will vary with wind, landing area etc. If you arrive at the point where you would normally start the front riser turn, and the picture's not right - abort it and land normally.
    Once you have the picture down, and are doing front riser turns that transition to gradual flares, then start increasing the angle. Once you get to 90 degrees you're going to be gaining a lot of speed, so be sure to adjust your sight picture up to compensate. As always, bail by dropping the risers if you feel like there's anything wrong. Once you drop the risers, level the wing with your toggles and prepare to flare. At worst you'll have to land crosswind - but that's a skill you should have by this point anyway.

    6. Land on slight uphills and downhills.
    Often, land away from the DZ isn't perfectly flat; sometimes you can't tell this until you're at 20 feet. To prepare for this, find a place in your LZ that's not perfectly flat, scope it out, and plan on landing there. There's not too much magic concerning landing on a slope. You flare more aggressively to land going uphill, less aggressively to land going downhill.
    Obviously not all DZ's have slopes. If you don't have a good slope on your DZ somewhere, you may have to put this one off until you're at a DZ that does have one. Beaches are a good place to practice this, since they have pretty predictable slopes down to the water, and overrunning the landing just means you get wet.

    7. Land with rear risers.
    Knowing how to land with rear risers can help you deal with a canopy problem like a broken or stuck brake line, and can help you make a better land/cutaway decision when you do have such a problem.
    Again, this is best practiced up high. See how far you can pull the rear risers before the canopy stalls. It will stall much earlier with rear risers; memorize where that happens so you don't do it near the ground.
    When you try it for real, choose an ideal day - steady moderate winds, soft ground, clear pattern. Be sure to try this for the first time on a largish canopy (one of the reasons you should do these things before downsizing.) Leave your hands in the toggles and wrap your whole hand around the rear riser. That way if things go awry you can drop the risers and flare normally. Start the flare at a normal flare altitude, and prepare to PLF. You may get the sort of lift you're used to, but you probably won't slow down as much before you're near that stall point. Make sure your feet are on the ground (sliding preferably) before you get there.
    On smaller canopies, you may want to start the flare with rear risers. Then, once the canopy is leveled out, drop the risers and finish the flare with the toggles (which are still around your hands.) That way you get your vertical speed to zero, which is the critical part of a safe slide-in landing, and can still stop the canopy without hitting the ground going too fast. (This is also a technique used by swoopers to extend their swoops BTW.)

    The above list is not meant to include all the skills you need to safely fly a canopy; it’s just a checklist for a cross-section of skills you should have before downsizing. Some of these will be easier on a larger canopy, and can be practiced right away. Landing downwind, for example, is easier on a larger canopy simply because it can slow you down more before stalling. Some skills are more difficult on a larger canopy. It can be difficult to get a planeout at all on a larger F-111 canopy, so practicing things like a flare turn may best wait until you approach a 1:1 loading on a ZP canopy. At that loading, the canopy begins to perform more along the lines of how we expect a HP canopy to fly. More importantly, skills like the flare turn become both possible and necessary to practice, so you can hone your skills while you are under a canopy that tolerates minor mistakes.
    As I mentioned in the beginning, these are skills you should learn before you downsize, although some (like the flare turn) can be difficult to practice at very light loadings. If you can't do some of them yet? Get some coaching; it makes a lot more sense to learn them on your larger canopy, before you start jumping a smaller canopy that scares you. Once you can do them all, then try the smaller canopy. And if someday someone cuts you off under the smaller canopy, you'll have the reactions you learned under the larger canopy. Even if you haven't completely adapted those manuevers to the smaller canopy yet, those reactions will more likely than not save your life.

    By billvon, in Safety,

    Five Quality Canopy Skills Every Beginner Should Have

    So you whipped through your student program, graduated AFF, moving towards or already got your A license, eyeing a rig to buy and well on your way to your first 100 jumps. Canopy or parachuting skills are an integral part of every training program, but are also the most important skills these days. There are five quality canopy skills every student should know: awareness of your rig and canopy, awareness of your self and others in the pattern, awareness of target and setup, good depth perception, and a proper two stage flare.
    A Few Parachuting Tips That Are Very Important

    1. Awareness Of Your Rig And Canopy
    Developing awareness of your rig comes with time. Unfortunately, when you're a student, time is not a comfort you always have. You need to be comfortable and confident with your rig on every jump. If it is a new rig you're jumping, wear it around the house, while your cooking dinner, sitting on the couch or doing chores so that you can get used to it.
    If you rent rigs, get suited up extra early like on the twenty minute call, so you can go through all your emergency procedures. This comfort and confidence is paramount when you are up in the air. If you are not confident in your parachuting equipment, you will have "gear fear" and this can affect your judgment.
    If you have a new rig and there are things you don't like about the rig, change them. You would be surprized the little things a rigger can do to make a rig fit better. I recommend buying a custom rig when you have reached a size you will be on for a while 190-170 sq feet on average. Even with a new rig, small alterations can be made. The easiest fixes that I see students can do is a bungee cord to connect your leg straps, padded reserve handle, shortening the closing loop, and modifying the laterals to make the rig fit tighter. All these modifications are freefly specific but a tighter rig is a safer rig.
    Know your canopy when parachuting. Know each stage of deployment and the equipment on your canopy which is responsible for each stage. Learn how to pack! Packing your parachute is an intimate way to get to know your equipment. If you can pack your rig well, you will more likely have a greater understanding of your equipment and confidence with it. Packing comes with experience. Pack at home over and over again, watch people pack, and ask lots of questions. If a packing course is offered, take it.
    I know when I was starting out, I wasn't that interested in my canopy. It was a docile vehicle to get me from 3,000 feet to the ground, which I had to pack every time to go up. I definitely feel different about my canopy now. When you are under canopy and not in the pattern above 1000 feet, play with your canopy, practice your landings over and over again. Experiment with front risers, rear risers and toggles.
    Two intricate tips with your equipment can improve the performance of your canopy immensely. The first is simple, stow your slider and bring it down behind your head. Keep weary of where you are located relative to the drop zone, and other jumpers. Don't mess with the slider as you might end up in another county. Stowing your slider helps reduce drag and can increase your glide. It also gets rid of that annoying flapping noise.
    The second tip is for a student who can land on his target consistently. After your slider is stowed elongate your chest strap all the way out, without undoing it. Practice on the ground. You want your chest strap to be as wide as possible for three reasons: the canopy is designed to fly like this as it increases the glide of your canopy, second it gives you another control surface to fly, that being your hips, and lastly it allows you to lean forward in your harness which gives you more control. All three of these points can be seen on a good canopy pilot and a moderate student can start practicing these skills early on in his career, even though it will play a bigger part later.
    When your chest strap is elongated your hips are now hooked directly to your canopy instead of your shoulders through the harness. It will be hard to turn the canopy with your hips at first especially with large canopies, but it can be done. Simply scissor your legs and throw the leading leg over the trailing leg and lean in to it. Then try it the other way. This will become more important when you get to sizes like 150 sq feet and below.
    A word of caution, don't spend too much time elongating your chest strap under the canopy while you are parachuting, you definitely will end up in a different county. Opening shock makes it more difficult to elongate the chest strap then on the ground. The buckles cinch up with opening shock to make sure you don't fall out. Do not undo your chest strap! If you elongate the chest strap properly you will not fall out of the harness. The canopy will feel slightly wilier but nothing dangerous. Stow your slider and elongate your chest strap before you unstow the brakes. This will make it infinitely easier. If you unstowed your brakes already, let the alterations go and remember to do these things on the next jump. You must have a certified instructor watch over you when you practice on the ground and in the air. Make sure these alterations are done before 1000-1500 ft. Be careful, use common sense.
    2. Awareness Of Your Self And Others While Parachuting
    I have briefly touched on this subject already, but since canopy collisions and landing off are a reality, awareness of yourself and others is a Quality Skill unto it self. Always know where you are relative to the drop zone. Are you up wind or downwind? Can't tell, figure it out! Watch the wind on the trees, or a nearby lake. Watch other skydivers, are they landing in the same direction your facing, or the opposite.
    I tell my students to watch the drop zone in the plane and where you are relative to it and the wind. This serves multiple purposes: you gain an awareness of where the pilot is in his jump run and his tendencies, you have a better understanding of the area you are jumping and potential outs and hazards, and on jump run you will be able to anticipate where you will be if you look out the window while other people are getting out.
    Look out for other people under canopy, especially during and right after opening. Check your canopy then look for others immediately. Look up and down the jump run for the people who got out before you and right after you. Get a visual then go through your checklists of things to do. If you are playing with your canopy up high always look before you turn or yank on a control surface. Find the pattern; be mindful of people out side the pattern. Do not spiral in the pattern. The best way to have clear space around you is to go last and deploy high.
    One easy thing that you can do especially when you are traveling to a different drop zone is find how they operate their pattern. You would be surprised how many experienced jumpers do not ask about or forget the pattern. I think this is the biggest problem at destination DZs where people are visiting. Follow the rules laid out; the rules are there for you as skydiver's safety and the safety of others.
    3. Awareness Of Your Target And Setup
    You should be aware of where your landing target is in freefall. I have left countless jumps early because the spot was off, people took to long in the door and spread the spot to thin, or the wind was stronger when we exited then when we took off. The point is, develop an awareness of where your target is in freefall by doing solos. Don't be afraid to deploy a little early if you see you are entirely too long to get back.
    After you are open and you have made sure the canopy is safe, you have made your control checks and alterations, size up the distance and altitude you have from your target. Execute the pattern your instructor and you have gone over. Try to stay up wind of your target before you start to execute your pattern. Go over in your head, how you are going to execute, see the legs of your pattern, check for others, and then go!
    Hitting your target is not done in the last 150 feet, that is how people get hurt. Hitting your target comes from proper briefing of the landing area before the jump, your spot, and how you set up for your pattern at 1000 feet. Good target acquisition comes from practice but also preparation.
    4. Good Depth Perception
    Depth perception is a key element of being a good canopy pilot. It is a learned skill but can be greatly improved through various techniques. If you wear glasses please tell your instructor. Do not be ashamed of your sight. Your sight will put you at a great disadvantage if you do not use your glasses or contacts while parachuting. With proper use of glasses and contacts you can enjoy the sport with no problems. If your goggles don't fit your glasses buy ones that do. If you do not like glasses and your contacts dry up, change your goggles to a snugger fit, or possibly look into laser surgery. I know many people in the sport who swear by laser surgery. The bottom line is that when you skydive, use what you use to drive your car. Skydiving is as critical as getting behind the wheel with your eye sight.
    If your sight isn't a problem or you use one of the corrective measures above, you can dramatically increase your depth perception of the drop zone and the ground. Look at the drop zone while you are in the plane and gage it with your altimeter so you get an idea of how high you are. Get a highly visible altimeter and don't forget it on the ground! When you get within the last 150 feet do a quick check for people around you, then lock in on your target. When you get 50 feet from your target, shift your eye sight from looking down to looking in front of you. Open your vision so you still include the ground but try to look forward. Begin your two stage flare at about 10-15 feet depending on the winds. Keep your vision open and wide; do not fixate on the target. Consult your instructor.
    5. A Proper Two Stage Flare
    I know some drop zones do not condone a two stage flare. Do not buck the trend on this one. If your drop zone doesn't allow it, come to me I will teach you. Ask your instructor about the two stage flare. I know from my experience some students have a tough enough time doing a symmetrical flare at the proper altitude. So maybe the two stage flare is not right for you, right now. I do believe it is an important part of being a good canopy pilot, and mixed with all the alterations mentioned above can give you your first swoops coming straight in with no riser input. In fact I have seen students who collapse and stow their slider, elongate their chest strap, and use a proper two stage flare swoop 50-60 feet with no wind.
    The two stage flare is quite simple.10-15 feet above the ground quarter flare your canopy. This action planes out your canopy and translates your vertical motion forward. Make sure that the flare is quartered not a half flare. There is a dramatic difference. A quarter flare will plane the canopy out and accelerate you forward; a half flare will distort your canopy and make you sink. When you are five feet above the ground, full flare to come to a complete stop. I see many people just leave the canopy in a quarter or half flare. This action makes you hit the ground moving forward and a little hard, you might have to run it out.
    Make sure you have a consistent symmetrical flare on target before you practice a two stage flare. The two stage flare is difficult without video to show you what you are doing. So, get coaching with video, people just telling you what to do will not get it done. You must have feedback and video is the best for this. Also if your instructor uses radio this is a plus, but not essential.
    I have commented on many things in this article. Do not try to do them all at once. Concentrate on one thing per jump. Focus on one thing for 20 jumps if you get flustered easily, till you get it right and it becomes habit.
    If you incorporate all these things with the over site of a quality coach, you can swoop coming straight in with no riser input on target safely negotiating others and the physical hazards around you. Be very careful under canopy while you are parachuting. Nothing replaces common sense, good judgment and asking lots of questions. You too can be an excellent canopy pilot with these five quality skills.

    Steven Blincoe has 4,000 jumps and 300 Skyventure hours in the wind tunnel. He is the founder of the New School Flight University in Orlando, Florida. He also has 10 years of experience in the sport coaching, competing, and filming. Steven Blincoe can be reached by phone 530-412-2078 USA, or by email [email protected]. You can also go to www.blincoe.org.

    By admin, in Safety,

    The Stall

    The stall is one of the least explored and most feared aspects of flying. Avoidance of this flight mode causes many canopy pilots to be uncomfortable with flying slowly, and unpracticed in this important art. This article will discuss the governing variables relating to the stall, in hopes that this knowledge will help parachute pilots to become less afraid of this essential aspect of the flying experience.
    First we must explore what a stall is. The assumption made by most canopy pilots is that the stall is caused by slow speed flight. This is not true. It is correlated with low speed flight, but a wing can stall at high speed too. A stall is caused by an excessive angle of attack. When the relative wind flows over an airfoil, it is bent in the general direction of down. This causes an opposite force called "Lift". When the orientation of the airfoil is changed to a higher angle with respect to the relative wind, it is said to have an increased angle of attack.
    Air is quite cooperative. It is willing to be redirected and still flow in a fairly organized manner…up to a point. At a specific angle, all airfoils fail to bend the air into submission. This discrete angle of attack is referred to as a stall. It is coupled with a sudden drop in lift, and thus a significant increase in decent rate. Whether you are flying an F-16 or a Lotus 190, recovery from a stall is always the same: the pilot must reduce the angle of attack. On an airplane this requires forward pressure on the yolk or stick. On a parachute, we are simply required to let off the downward pressure on the toggles or rear risers that has increased the angle of attack in the first place.
    Each parachute stalls and recovers differently. Depending on several governing variables, some parachutes will recovery nicely from a stalled configuration no matter what the recovery technique, while others will require very careful execution. Let's take a look at these issues one by one.
    The characteristics of a stall on any ram air canopy are based on two main variables, and several lower order variables. The most significant governing variable is the flight mode when the stall is reached. If the canopy is in a sink, rather than level flight (zero decent surf), it will tend to stall in a more forgiving and docile manner. The second primary variable is the attitude about the roll axis when the stall is reached. In other words, if there is any bank angle when the stall precipitates, it will cause the lower wing to stall first, resulting in significant yaw energy, which can result in line twists.
    There are several other things to consider when testing the stall of a canopy, including: canopy design, density altitude, wing-loading, aggressiveness of the control input, and most importantly, recovery technique. This will be discussed next.
    If the wing is allowed back into forward flight quickly, it will dive aggressively toward the ground, causing a drop in the angle of attack, as well as the lift and therefore the overall line tension. This may allow the wing to surge below the suspended weight (you), and possibly cause a jumper/canopy entanglement. Further, if the release of the brakes is asymmetrical, the lack of line tension can allow the wing to surge unevenly about the yaw axis, causing line-twists.
    The key to stalling any wing is to enter the stalled configuration in a sink, with the wing level and static about the roll axis. As soon as the stall is reached, the toggles (or rear risers) should be released only a few inches to allow for only a slight drop in the angle of attack. As soon as the brakes are released, the jumper should be prepared for a sudden increase in toggle pressure, as the tail of the parachute is about to get hit with a pulse of relative wind. If the pilot is unprepared for this, the toggles will usually be pulled upward and possibly in an uneven manner, often resulting in an aggressive stall recovery that may result in line twists.
    When the brakes are released quickly to the full flight position, the wing doesn't have much drag. This means that there is very little to prevent it from surging forward in the window. When the brakes are released slowly, and then held down just above the stall point, the wing has a great deal of drag. You have two big barn doors at the back of the wing helping to prevent and aggressive surge.
    Further, as you become more familiar with the stall and recovery characteristics of your wing, you may begin to fly "actively" with respect to the recovery process. In other words, as soon as the wing begins to fly forward in the window, the pilot jerks on the brakes to dampen the forward surge. It is important to do this minimally enough to prevent re-stalling the wing. A well-timed reapplication of the brakes during the recovery process will significantly reduce the amount of altitude lost in the stall. This can be very useful in the event of a low altitude stall. This maneuver can be practiced in relative proximity to another canopy in deep brakes. Be sure to keep your distance when you do this. By definition, a stall is a loss of control of the wing.
    Rear riser stalls tend to be sharper at the onset, but quicker on the recovery. Therefore it is advisable to stall the parachute on the rear risers first before attempting to stall it on the brakes. Further, such maneuvers should always be performed at an altitude that will allow for a safe cutaway.
    Given all of these concerns, one must ask "Why should I stall my parachute in the first place". There are several valid reasons why each jumper should rehearse stalls at altitude.

    In high angle of attack approaches, such as may be necessary in a tight landing area, stalls can happen inadvertently while maneuvering. This is why it is also important to practice slow flight maneuvering by lifting the toggle on the outside of the turn, rather than depressing the one on the inside of the turn.
    In order to reach a (near) zero ground-speed on a no-wind day, the pilot must have full "Toggle Authority". In other words, if the toggles are set too long, the pilot will be unable to access the slowest possible airspeed, and therefore will be forced to land with more ground-speed without the advantage of a headwind. Being able to finish the flare completely and then let up after landing to prevent the stall from pulling you onto your heels in an essential part of any no wind landing.
    When you decide to practice stalls, I suggest taking the process step by step. Simply honking your brakes down with your eyes squinting in negative expectation usually results in a wild ride, and sometimes a cutaway. Try hanging out in slow flight for a while. Bring your toggles down to a bit more than half brakes and leave them there. If you are above the stall point, it isn't going to just stall all by itself. Watching people fly in deep brakes is usually similar to watching them light a firecracker. Your parachute isn't going to explode…promise.
    When you get your canopy into the deep brake mode, take a deep breath in and let it out slowly. Relax your muscles. Let your legs hang limp. I find that nervous pilots can't connect with their parachute because it isn't touching their bones. If you soften your muscles, your will allow the leg straps to sink into you so that you can feel what is happening with the newest addition to your body: your wing. By truly relaxing under canopy, we begin to sober up from the adrenalin that is blurring our vision and skewing our perspective toward the negative.
    Stalls are an essential part of flight. If you are to be fully in control over the wing, you must explore all aspects of your parachute's performance envelope. Ultimately, flying slowly is the most important aspect of flight because we land in slow flight. The more comfortable you are with your slow flight skills, the better your touchdown will be. Remember, the definition of a good flight is one that ends well.
    BSG
    www.BrianGermain.com
    BIGAIR SPORTZ

    By BrianSGermain, in Safety,

    Collapses and Turbulence

    There are many variables to consider when looking into a canopy collapse:
    What was the pilot doing?
    How fast was the canopy flying when it collapsed?
    Where was the pilot flying?
    What is the canopy design?
    What is the wing-loading?
    Was there any re-active solution employed? These are the principle considerations, but not the only ones. I will take each one separately.
    1) The way in which a parachute is flown can increase or decrease the "G" loading on the lines. A rapid release of one or both brakes significantly increases the chances that the canopy will collapse. This allows the parachute to surge forward to a lower angle of attack, decreasing the lift of the parachute. This reduces the amount of energy exerted by the parachute away from the suspended load, allowing the "negative" portion of the lift to take over and allow the wing to fly towards the jumper.
    2) Airspeed is what creates lift. Lift is what causes the wing to strive to fly up and away from the jumper. This is the formula for line tension and therefore stability. The slower you are flying, the more likely your parachute will collapse due to low internal pressure and low line tension.
    3) Was the wing flying in clean air when the collapse occurred? This is an important part of the question. All parachutes can collapse in "bad" air. We must always fly considering the invisible dangers that the sky presents us. If you wouldn't fly a kite there, don't fly or land your parachute there.
    4) Certain parachute designs do better in turbulence than others. I must avoid pointing fingers here, as this is a volatile industry that can be taken down by non-skydiving lawyers. Nevertheless, certain wings have an increased propensity to go "negative" when presented with adverse condition, while others bump around a bit and keep on flying. This is a complex issue, and the best way to decide which parachute to buy and fly is to listen to the actual statistics, and to your own experience when flying a particular design. I have not experienced any kind of collapse on the parachutes I fly, ever.* If you have on yours, you may want to reconsider what is over your head.
    *(This does not include nasty, ill-conceived prototypes that seemed like a good idea at the time. I am talking about production-model canopies here)
    5) Parachutes perform differently at different wing loadings. The lighter the wing loading, the slower it will fly. This means that the internal pressurization of the wing will be less on larger canopies. In general, lightly loaded parachutes experience more small collapses than heavily loaded ones. Not only is there less internal pressure in the wing, but the dynamic forces area also less with decreased airspeed. This means that the average line tension tends to be less on a lightly loaded wing, and the wing tends to have a increased propensity to surge forward in the window when flying at low air speeds. This is why very small, highly loaded parachutes tend to experience fewer distortions, especially when flown at high speed. Flying at high speed increases the drag of the canopy itself, relative to the jumper, so the relative wind holds the parachute back in the window and at a higher angle of attack. This is why I make carving, high "G", high speed turns to final approach heading, especially in turbulence. The speed actually reduced the chances of a collapse by increasing the forces that keep the parachute at the end of the lines. I am literally increasing my wing loading by flying fast and at high "G's", and the increases velocity reduces the amount of time that I fly in bad air. I am not saying that you should downsize just to increase your stability. I am saying that until your skills and knowledge are ready to fly smaller, faster parachutes, you should stay out of the sky until the winds come down. I still haven't been hurt by a jump I didn't do.
    6) This is all about "Pitch Control". If you are flying a good design with lots of airspeed and significant line tension, and in a reasonable location that has no obvious precursors for collapse, you can only deal with a collapse in a re-active manner, as you have addressed all of the relevant variables up to this point. If your wing tries to aggressively surge forward in the window, you must notice it and quickly stab the brakes to bring it to the back of the window. A collapse always begins by a surge to a low angle of attack, but there is very little time to deal with the problem before I folds under. Here are the signs:
    The first sign is a change in Pitch. The wing moves forward in the window. This is the limited flying space over your head. Too far forward and it collapses. Too far back and it stalls.
    The "G" loading drops dramatically and almost instantly. In other words, your apparent weight in the harness drops because the wing is producing less lift. This is the time to jerk on your brakes: quickly, sharply, but not more than about 50% of the total control stroke. This action is to pull the wing back in the window, not to stall the parachute. By putting the wing further back in the window, we are increasing the angle of attack. This increases the lift, and forces the wing to fly away from the suspended load and thereby increase the line tension. This can prevent a collapse entirely, or cause the wing to recover to stable flight before things get really out of control.
    If the wing is allowed to collapse, it may recover quickly on its own. This is why the more modern airfoils have the fat point (Center of Lift) so far forward. It causes the wing to pitch nose-up when it begins to fly again, bringing it back to the end of the lines. Nevertheless, parachutes can still collapse fully, which often involves significant loss of altitude and possibly a loss of heading. If your wing goes into a spin because of a collapse, your job is to stop the turn first, as you increase the angle of attack. If it is spinning, there is less chance of recovery until the flight path is coordinated and the heading stable.
    Conclusions:

    Don't fly an unstable parachute. If it is prone to collapse, ground the parachute. Do not sell it to an unsuspecting jumper at another drop zone. These people are your brothers and sisters.
    Don't fly in crappy air. Land in wide open spaces, in light winds, and never directly behind another canopy.
    Practice stabbing your brakes in response to forward surges on the pitch axis. This must become a "learned instinct" that requires no thought at all. Like pulling emergency handles, pulling the wing to the back of the window when the lines get slack is essential for safe skydiving.
    Keep flying the parachute. If your parachute does something funny near the ground, don't give up. If you keep your eyes on YOUR ORIGINAL HEADING, you will unconsciously do things that will aid your stability and keep you from getting hurt. Looking toward what you don't want is how you make it occur. I hope this little article helps you understand the phenomenon of collapses a bit better. I know as well as anyone how painful a collapse can be. I do not want to go back to that wheelchair, and I don't want anyone else to have to experience that either. You morons are my family, and if information can help protect you, I will give it until my lungs are out of air.
    Blue Skies, Sky People.

    Bri
    Article Discussion

    BIGAIR SPORTZ

    By BrianSGermain, in Safety,

    Skydiving Incident Reporting: For Mass Media Reporters

    Reporting a skydiving (or any other technical sport) accident isn't an easy job, but making the effort to do it thoroughly can give your readers a better product that tops competing publications in this area. Why is improving coverage of this relatively rare event important? The reason is because turning out boilerplate or inaccurate coverage of these incidents angers many skydivers, who might then become ex-readers, and gives the non-jumping segment of your audience nothing special to take away from the story and thus doesn't reinforce your publication's brand.
    Accuracy, Not Generalities
    Before you think I'm suggesting that you write a full investigative report of any sport accident, let me say that I don't suggest any additional words in your reports. What I am suggesting is making those words count, with more solid information. Often the sentences that appear in skydiving accident coverage are misleading as to the true nature of the accident. For example, the explanation of "The parachute failed to open" that is so often used in such reports is not a simplification for an audience uneducated about skydiving; it's just plain wrong nearly all the time. It's comparable to saying of a single-vehicle accident, "The car failed to stay on the road," implying that the car is at fault rather than the driver.
    Such a statement implies that the skydiver did everything in his power, correctly, and still his/her equipment failed to function. However, this is exceedingly rare-occurring far less often than once per year. What is far more common is that a skydiver makes a mistake landing a perfectly good canopy (39% of the 35 U.S. skydiving deaths in 2002, the most common cause of death), collides with another skydiver in freefall or under his parachute (21% of the 2002 deaths), or fails to respond correctly to a survivable equipment malfunction (12% of the 2002 deaths). (Note: skydivers do carry reserve, or backup, parachutes; a malfunction of the main parachute does not automatically kill the skydiver.)
    We all like to think that we'll make all the right decisions when the chips are down, but the unfortunate truth is that nearly all skydiving deaths are caused by "pilot error"-a mistake on the part of the skydiver. This doesn't mean that we have to crucify this person who made the mistake, but we shouldn't imply that the equipment was at fault when it wasn't necessarily the main factor in the accident.
    Getting the Scoop
    Reporting the specific cause of sport accidents gives more "meat" to your story, which both your skydiving and non-skydiving readers will appreciate. But how do you know what to write when you're not a skydiver and don't understand the topic you're supposed to report? Work with the experts-foremost of whom is that drop zone's safety and training adviser (S&TA). The S&TA is an individual appointed at almost every drop zone in the U.S., and abroad, by each Regional Director of the United States Parachute Association (USPA), regardless of whether or not the drop zone is a Group Member of USPA. This individual is tasked with many different safety and administrative-related duties at their appointed drop zone, one of which is investigating skydiving accidents and fatalities. Investigating incidents is one of the less enjoyable responsibilities of an S&TA.
    Other interview possibilities include the coroner (if the skydiver involved is deceased) and the rigger (person licensed by the Federal Aviation Administration to pack reserve parachutes, and usually knowledgeable about skydiving gear malfunctions) who inspected the gear--if applicable and if the S&TA directs you to talk to this person. A third possibility is the drop zone owner/manager if an S&TA is not available. The USPA is a good source of general skydiving information, but is not a good source of information on specific incidents.
    The local sheriff or a representative often becomes a media liaison by default, but unless this person is a skydiver working closely with the drop zone's S&TA, then working only with this person is not good. A sheriff with no skydiving experience is no better information source on a skydiving incident than a reporter with no skydiving experience, and will often garble information he or she is given simply through unfamiliarity with the topic.
    Ask the previously listed skydiving professionals to explain to you, in layman's terms, the cause of the accident so that you can accurately report it. They may not yet have all the answers, especially if certain equipment malfunctions are suspected, but if you are polite and interested rather than forceful about getting the story before an early deadline you will get a lot more cooperation. A good working relationship with the drop zone in question is ideal, because not only will this help you on this story, but you will also get a much better story for other drop zone events such as charity fundraisers (skydiving is interesting to your non-skydiving readers, and can sell publications when good events happen as well as accidents).
    Introducing more specifics to your report will be good for your readers, but more information requires more fact-checking. If possible, send a copy of the article to your source at the drop zone before publication. The source will likely jump (pardon the pun) at the chance to review the coverage for accuracy.
    Don't Make These Mistakes
    Skydivers do not skydive because of a death wish. If that were the case, they'd only make one jump apiece. They most definitely are thrill seekers, but they are dedicated to skydiving safely, even while pushing the envelope, so they can continue to skydive. Portraying skydivers and skydiving as irresponsible, imminently dangerous, or suicidal is an inaccurate disservice.
    It is also inaccurate to imply that drop zone management is to blame for most skydiving deaths, because it is every skydivers' choice to exit the aircraft; once they have done so, the only person who can keep one safe is himself/herself. For the most part, blaming a drop zone for an experienced skydiver's death (nearly always skydiver error, as previously stated) is similar to blaming the highway system for a motorist's death. The system simply provides the place for the motorist to drive; the drop zone merely provides an aircraft and landing area for the skydiver to jump and land. What a skydiver does with those resources is his or her responsibility alone.
    Also, keep in mind that stating or implying that a drop zone is to blame for an incident could lead to a libel suit if there is no evidence to back up the accusation.
    While the following isn't technically a mistake, it is the author's firm belief that in most cases, the practice of including a roll call of any deaths that have previously occurred at a drop zone (or any other sports facility) with an accident article serves no good purpose. If all of these deaths were attributable to the management or equipment provided by the drop zone, then there is something going on that should be exposed. Without proof of such culpability, however, listing previous deaths generally just angers skydivers and creates the mistaken assumption by non-skydiving readers that there is something going on that should be stopped. Again, keep libel laws in mind.
    Jump Plane Accidents
    Thankfully even less common than skydiving fatalities, jump plane accidents present a different reporting challenge mainly because aviation accident investigation falls under the authority of the National Transportation Safety Board (NTSB). The local skydivers might or might not have an aviation and accident investigation background, and might or might not know the cause of the accident; they are not the people you should interview about aircraft incidents. Just because the accident involved a jump plane doesn't make it a skydiving accident. The pilot would be a good source if he survived, but NTSB is the final authority on aircraft accidents, and their reports tend to take some time to come out. They do send public affairs officers to the scene of aircraft accidents; these people are the ones you should talk to in this instance. Resources for journalists regarding aviation accidents can be found on their web site at www.ntsb.gov/events/journalist/default.htm.
    The end goal of this article is more informative, balanced, tasteful reporting of skydiving and other sport incidents in order to better serve readers and thereby the commercial publications they purchase.
    Thanks to Randy Connell, S&TA, S/L Instructor, AFF Instructor; Chris Schindler, ATP, CFII; and Jim Crouch, AFF/I, USPA Director of Safety and Training, for their contributions to this article.
    Resources:

    www.uspa.org

    www.ntsb.gov

    Christy West is a journalist and gold/silver skydiving medalist with over 1,800 jumps.

    By admin, in Safety,

    Skydiving Glossary

    This glossary of skydiving terms accompanies the Student Skydiver's Handbook, by Bryan Burke.
    Click on the letter corresponding to the first letter of the word you are looking for:
    A B C D E F G H I
    J K L M N
    O P Q R S
    T UV W XYZ
     
    Return to the top of the Glossary to search for more words or just browse them alphabetically.
    The Letter A
    AAD. Automatic Activation Device. A device that senses rate of descent and altitude and which will attempts to mechanically activate the reserve parachute if the skydiver passes below a set altitude at a high rate of descent.
    A/C. Aircraft.
    Accuracy. Also known as Precision Landing, this is a competition discipline in which the skydiver attempts to land on an established target. At the National level the target is 3 cm in diameter, about the size of a quarter. Accuracy landings of various difficulty, from 20 meters to 2 meters, are required for USPA licenses. See the SIM for details.
    AFF. Accelerated Free Fall. An AFF student receives training on freefall jumps of 40 seconds or longer, accompanied by a qualified jumpmaster,
    as opposed to Static Line training which does not involve long freefall in the initial training phase.
    AGL. Above Ground Level. Altitudes are in reference either to Ground Level of Sea Level (see MSL). Skydivers always use AGL when referring to
    altitude.
    Airspeed. The speed of a flying object through the air, commonly used in reference to aircraft or canopies.
    Altimeter. A device indicating altitude.
    Angle of attack. The angle at which the wing is presented to the apparent wind. With square parachutes this changes when the brakes are
    applied.
    Angle of incidence. The angle at which a canopy is trimmed to glide through the air.
    Apparent wind. The wind perceived by an observer. See relative wind.
    ASP. Skydive Arizona's version of AFF, the Accelerated Skydiving Program includes two tandem jumps and an enhanced version of the AFF
    syllabus.
    ASTRA. An AAD made by FXC Corporation.
    Aspect ratio. The ratio of a canopys width (side to side) to breadth (front to back). Seven cell canopies typically have an aspect ratio of about 2.2 to one, while nine cell canopies are usually between 2.8 and 3.0 to one.
    The Letter B
    Backslide. To move backward in freefall relative to a neutral reference. Usually unintentional and undesirable, caused by poor body position.
    Bag. The deployment bag in which the canopy is packed.
    Base. The core around which a formation skydive is built. Can be a single person or a group of people, depending on the number of skydivers involved.
    BASE jump. A jump made from a fixed object rather than an aircraft. BASE is an acronym for building, antennae, spans (bridges) and earth
    (cliff).
    Beech. Short for Beechcraft, an aircraft manufacturer. Usually used in reference to a Beech D-18, a.k.a. Twin Beech. At one time these were common skydiving planes, but they are becoming obsolete.
    BOC. Bottom of Container. Refers to the location of the pilot chute. An increasingly common position for main deployment devices, as opposed to belly or leg mounted.
    Body position. Ones freefall body posture. Variations in body position are what make a wide range of freefall maneuvers possible.
    Boogie. A gathering of skydivers, usually focused on fun rather than competition. Big drop zones host several boogies a year, often on long holiday weekends.
    Bounce. To land at unsurvivable speed. Also to frap, or go in.
    Box man. A neutral, face to earth body position in which the arms form right angles at shoulder and elbow, and the legs are spread at about 45 degrees from the long axis and bent 45 degrees at the knees. Generally considered the ideal position for Formation Skydiving.
    Brakes. The brake lines of the canopy are synonymous with steering lines. Used together, they slow the parachute. Used independently they result in a turn.
    Break off. To cease formation skydiving by tracking away from the formation prior to deployment.
    Bridle. The thin webbing strap from the pilot chute to the top of the canopy. Part of the deployment system which consists of pilot chute, bag and bridle.
    BSR. Basic Safety Requirements. BSRs are USPA guidelines. They do not have force of law but are generally regarded as excellent minimum safety standards.
    Burble. The area of turbulence behind an object going through the air, whether a person in freefall or a canopy in flight.
    The Letter C
    Call. The time remaining until you are to board the aircraft. For example, a fifteen minute call means you will board in fifteen minutes.
    Canopy. The construction of fabric and lines used to land safely after a freefall. Usually used in conjunction with a type reference (round, square, zero-p, main or reserve).
    Cascade. The point where two lines join together so they run smoothly into one. Cascading the suspension lines results in reduced bulk and drag.
    Cell. Square canopies are made up of pressurized cells, usually seven or nine. Each cell consists of a load bearing rib at each side to which the suspension lines are attached. A third, non load bearing rib runs down the middle of the cell. The cell is pressurized through the open mouth at the front and also through cross ports in the ribs. Adjacent cells share load bearing ribs.
    Center point. The point around which movement takes place. In an individual the center point is considered to be in the middle of the torso. In a group, it is the point that the formation centers around.
    Cessna. An aircraft manufacturer. Single engined Cessnas such as 180s, 182s and 206s are the workhorse of smaller drop zones, carrying four to six jumpers.
    Chute assis. French for sit flying, or freefalling with one's seat presented to the relative wind.
    Closing loop. The small loop that holds the flaps of the container closed once the pin has been guided through the loop.
    Coach. A skydiver with some formal training in the art of instructing freefall technique.
    Container. The element of the parachute that houses the canopies. Technically, the Harness/Container but usually just referred to as the container.
    Crabbing. A canopy is crabbing when it is flown at an angle sideways to the ambient wind, resulting in a path across the ground that is sideways as well as forwards.
    Creep. To creep is to practice formation skydiving sequences while laying prone on a creeper.
    Creeper. A board equipped with wheels on which a skydiver lays to simulate freefall maneuvers.
    Cross ports. Holes in the ribs of a cell that allow air to flow from one cell to another.
    Current. To "be current" is to have jumped recently enough to retain proficiency in the sport. Uncurrent skydivers, depending on their experience, must be supervised to some degree when they resume jumping. See the SIM.
    Cut away. To release the main parachute, cutting away is a standard emergency procedure prior to deploying the reserve. More properly known as a breakaway, the technique did involve using a simple release system activated by pulling a handle.
    CRW. Canopy Relative Work, now officially known as Canopy Formations. CRW involves flying open canopies in close formation, where the pilots actually take grips on each other's parachutes.
    CYPRES. A type of AAD. Made by AirTech of Germany, this is the most common type of AAD and the first modern design to be widely adopted by expert skydivers.
    The Letter D
    DC-3. A type of aircraft, the Douglas DC-3 is a large, twin engined airplane capable of carrying over 40 jumpers. Like the Twin Beech, DC-3s are being rapidly replaced by more modern turbine engined aircraft.
    De-arch. To flatten out or reverse one's body position from the normal arched box man. A de-arch results in a slower fall rate than an arch.
    Dacron. A common construction material for canopy suspension lines. Dacron lines are thicker and softer than so called "microlines".
    Data card. Every parachute carries a data card with information on the reserve parachute, including type, last date packed, owner, serial number, etc.
    Dead spider. Slang for de-arch.
    Decision altitude. The altitude at which a skydiver is trained to begin execution of emergency procedures. Usually 2,500 feet AGL for students, and 1,800 feet for expert skydivers.
    Deployment system. The components of the parachute that control deployment of the canopy. Includes pilot chute, bridle and bag.
    Dirt dive. To rehearse a skydive on the ground.
    Dive floater. A dive floater is a skydiver who is inside the airplane in the exit line up, but leaving prior to the base. This configuration only occurs on large formations.
    Dive loops. Many advanced skydivers have loops or "blocks" on their front risers to make it easy to grip the front risers for steering purposes. Also called front riser loops.
    Diver. Anyone diving out of the plane during a formation skydiving exit.
    Door jam. To practice an exit in the aircraft door of a mock up of it prior to the skydive.
    DOS - Double or Dual Action System
    Down plane. A CRW formation with two canopies, both pointed toward the ground. This can also occur to a single skydiver with both main and reserve deployed.
    Drop zone. Common slang for a skydiving center, also DZ.
    Dytter. A brand of audible altimeter.
    The Letter E
    Elliptical. A wing shape characterized by a tapering leading and trailing edge so that the middle of the canopy is wider, front to back, than the ends. This configuration is typical of many high performance canopies.
    End cell. The cell furthers out on a canopy.
    Exit weight. The total weight of the jumper and all equipment and clothing.
    The Letter F
    F-111. A fabric common in mid range canopies, F-111 is slightly permeable to air and wears faster than zero-p fabric. Pronounced "F one eleven".
    FAA. The Federal Aviation Administration is the agency of the US government that regulates aviation activity, including skydiving.
    FAI. Federation Aeronautique International. The international organization governing air sports.
    FARs. Federal Aviation Regulations, the laws governing aviation.
    Fall rate. The speed at which a skydiver falls. Matching fall rate is essential to successful formation skydiving. This is done with jumpsuits, weights and body position.
    Finger trap. A method of installing a loop in a brake line without producing rough spots on the lines, the finger trap is accomplished by sliding one line into the other. The loop serves as a method of setting brakes in the desired position for the parachutes deployment.
    Flare. The act of pulling down the brakes of the canopy in order to slow it down, resulting in an increased angle of attack and reduced descent rate.
    Floater. Skydivers who leave the airplane before the base are called floaters since they must use a slow fall rate to get up to the base. Floating also refers to an exit position outside the airplane.
    Freestyle. A type of skydiving characterized by acrobatic individual flying, reminiscent of gymnastics.
    FS. Formation Skydiving, formerly known as relative work. In FS, skydivers attempt to go through a predetermined sequence of freefall formations.
    Formation. 1) A freefall skydiving formation of more than one jumper. 2) A flight of more than one jump plane.
    Funnel. A funnel occurs when one or more skydivers find themselves in an unstable body position and end up in a skydivers burble. The resulting loss of stability for the other skydivers usually causes the formation to break up.
    FXC. A company manufacturing AADs. One FXC design is common on students but considered by many to be unsuitable for expert skydivers. A new FXC design, the ASTRA, went on the market in the spring of 1996 and is relatively unknown.
    The Letter G
    Glide ratio. The distance a canopy flies forward compared to down. A canopy with a 3:1 glide ratio flies three feet forward for every foot of vertical descent.
    GPS. Global Positioning System. By picking up signals from satellites, a GPS receiver can tell the user position over the ground. Used in skydiving aircraft to spot the exit.
    Grips. Using the hands to hold onto another skydiver in freefall or during the aircraft exits. In formation skydiving, the formations are scored as complete when every skydiver has taken the correct grips.
    Grippers. Hand holds built onto formation skydiving jumpsuits to make it easier to take grips.
    Ground speed. The speed of an airplane or skydiver over the ground, as opposed to through the air.
    The Letter H
    Hand deploy. To activate the parachute by manually deploying the pilot chute as opposed to pulling a ripcord.
    Harness/container. The webbing and fabric holding the main and reserve canopies to the skydiver.
    Heading. The direction an aircraft, skydiver, or parachute is facing. The ability to recognize and maintain heading is crucial to jumping
    with others successfully. "On" or "off" heading are terms commonly used to describe exits and deployments.
    Holding. When a parachute is flying directly into the ambient wind, it is said holding. See running and crabbing.
    Hook knife. A small knife carried in the jumpsuit or on the parachute harness, the hook knife is designed to cut lines or webbing. A small razor blade is recessed in a hook shaped handle to prevent unintentional cuts.
    Hook turn. A turn of 90 degrees or more executed close to the ground. Because of the high risk associated with this maneuver, hook turns have an unfavorable connotation.
    Hot fuel. When the airplane does not shut down during fueling. Do not board the aircraft while fueling is in progress.
    The Letter I
    In date. A reserve packed within the previous 120 days is said to be "in date". If more than 120 days have elapsed since the reserve was packed it
    is"out of date" and illegal to use.
    Instructor. Someone who has held a USPA jumpmaster rating for at least one year and passed an Instructor Certification Course.
    IPC. The International Parachuting Commission oversees sport parachuting. It is a committee of the FAI.
    The Letter J
    Jump run. The flight path taken by the jump plane to put the skydivers in position over the airport.
    Jumpsuit. A cover all type garment designed for specific skydiving applications such as FS, freestyle or accuracy.
    Jumpmaster. Someone who has successfully attended a USPA Jumpmaster Certification Course. A jumpmaster has all of the privileges of an Instructor except that they cannot supervise a first jump course, sign off licenses, or manage a student program without an instructor's supervision.
    The Letter K
    Key. A signal to move on to the next step in a skydive.
    King Air. A turbine aircraft made by Beechcraft and common in medium sized drop zones.
    The Letter L
    Line of flight. An imaginary line corresponding to the jump plane's path over the ground, the line of flight is a useful reference line on larger formation
    skydives. Also, during the jump run the skydivers will be distributed along this line of flight.
    Log book. Like pilots or sailors, skydivers log their activity and achievements in order to document their experience.
    LORAN. A navigational system similar to GPS except based on ground transmitters, LORAN is relatively obsolete.
    The Letter M
    MSL. Mean sea level. Used by pilots when defining altitude, MSL refers to feet above sea level as opposed to above the ground. Pilots always use MSL when referring to altitude.
    Main. The primary parachute.
    Manifest. 1) The list of skydivers on the jump plane. 2) The act of going to the office where this list is maintained to put yourself on a plane. 3) The location where manifesting takes place.
    MARDS - Main Activated Reserve Deployment System
    Microline. A modern type of suspension line considerably smaller than dacron line.
    The Letter N
     
     
    The Letter O
    Organizer. Someone with leadership skills and skydiving expertise who plans formation skydives.
    Otter. The DeHavilland Twin Otter, a very popular turbine jump ship carrying up to 23 jumpers.
    Out landing. Landing off target.
    Out of date. See in date.
    The Letter P
    Packing data card. See data card.
    Peas. Pea gravel, used in the landing area as a target reference and because it is forgiving of hard landings.
    Pin. 1) The skydiver who first gets to the base. Base/pin are the two people around which many formations are built. 2) The act of docking
    on the base. 3) The closing pin of the main or reserve container, which should both be checked prior to jumping.
    Pit. The pea gravel area.
    Pilot chute. A small, round parachute that acts as a drogue to extract the main parachute from the container and deploy it.
    PLF. Parachute landing fall. A technique used to minimize injury during rough landings, a PLF distributes the landing shock along feet, calves, thighs, hip and shoulder.
    Porter. A single engined turbine aircraft carrying up to ten jumpers.
    Post dive. Review of a skydive after everyone has landed.
    PRO rating. A USPA rating indicating competence to perform difficult demonstration jumps.
    Pull out. A type of hand deploy pilot chute where the pilot chute is packed inside the container and pulled out using a handle with a lanyard to the pilot chute.
    Pull up cord. A piece of cord or line used to pull the closing loop through the grommets of the container.
    Pud. Slang for the handle on a pull out pilot chute system.
    The Letter Q
     
     
    The Letter R
    RSL. Reserve static line. This is a line from the main risers to the reserve cable. In the event the main is cut away, it may pull the reserve pin.
    Note: this system is only effective in malfunctions where the main is at least partially deployed.
    RW. Relative work, the term used to describe formation skydiving until a change in nomenclature made by the International Parachuting Commission in the early 90s.
    Relative wind. The apparent wind felt by a jumper in freefall, relative wind is the result of the skydiver's speed through the air.
    Reserve. The auxiliary parachute carried on every intentional parachute jump.
    Rip cord. The deployment system on all reserves and most student parachutes. The ripcord is a piece of cable with a handle at one end and a pin at the other. When pulled, the pin comes out of the closing loop holding the container shut, and the pilot chute is released.
    Rig. Skydiver slang for the entire parachute, including main and reserve canopies and the harness/container.
    Rigger. Someone with a certificate from the FAA stating they have successfully met the requirements to be a parachute rigger.
    Rigger's certificate. The certificate possessed by a rigger as proof of competence. Senior riggers may make minor repairs and pack reserve and main parachutes. Master riggers may make major repairs and alterations as well as packing parachutes.
    Risers. The webbing that connects the harness to the suspension lines. At the bottom of the risers will be a mechanism for attaching and releasing the risers and harness, usually in the form of a three ring release. On the rear risers are the brakes/steering lines. The suspension lines attach to the top of the risers with connector links, also known as rapid links.
    Round. 1) A formation where each skydiver has grips on the arms of those next to him, also known as a star. 2) A round parachute, as opposed to a modern ram-air "square" parachute.
    Running. When a canopy is flying with the ambient wind it is said to be running. This produces the greatest possible ground speed.
    The Letter S
    S&TA. Safety and Training Advisor. The S&TA is a volunteer representative of USPA who attempts to disseminate information about safety and act as a liaison between the DZ and USPA. Most S&TAs hold instructor ratings.
    SCR. The oldest award for formation skydiving achievement, for those who have been in a star of at least eight people in which each person left the aircraft separately and flew to the formation.
    SIM. Skydiver's Information Manual. Published by the USPA, the SIM is a comprehensive manual on USPA policies and training methods. It also
    includes FARs pertinent to skydiving.
    SOS. Single Operation System. This system simplifies emergency procedures by combining the functions of the cut away and reserve handles in a
    single handle.
    Seal. Reserve parachutes have a small lead seal on a piece of red thread around the closing pin. This seal indicates the reserve has not been
    opened since it left the riggers hands.
    Sentinel. A type of AAD.
    Single operation system. See SOS.
    Skygod. Although on the surface this term refers to a superior skydiver, in drop zone use skygod is a derogatory term for a skydiver whose ego has grown faster than his skydiving ability.
    Slider. A rectangular piece of nylon fabric with a grommet at each corner through which the canopy's suspension lines are routed. Packed at the top of the lines, the slider controls the opening of the canopy by preventing the parachute from expanding too rapidly.
    Slot. A position in the skydive or on the plane. Uses: "dock in your slot", or "two slots left on the next Otter".
    Spectra. A material from which microline is made.
    Spot. The position of the aircraft when the jumpers exit. Spotting duties (selecting the spot) can be done by a skydiver or the pilot.
    Square. A ram air parachute as opposed to a round parachute.
    Stabilizer. The vertical strips of cloth depending from the end cells of the canopy. Stabilizers improve the canopy's ability to fly straight ahead and enhance efficiency by reducing tip vortices.
    Stall. When the angle of attack of a wing becomes too high to sustain lift, the wing is said to be stalled.
    Static line. In static line deployments the parachute deployment system is attached to the airplane, with a cord ten to fifteen feet long, resulting in deployment immediately after exit.
    Steering lines. The lines that run from the steering toggles on the rear risers to the trailing edge of the parachute.
    Steering toggles. Handles attached to the end of the steering lines to facilitate their use. Toggles and lines are configured so they can be stowed in a partially down position to enhance the opening of the parachute.
    Stow. To neatly arrange suspension lines on the deployment bag or steering toggles in their keepers.
    Style. A type of freefall competition where an individual skydiver attempts to execute a predetermined sequence of maneuvers in the shortest
    possible time.
    Suspension lines. The lines from the risers to the canopy. They are normally in four groups, labeled from front to back as A, B, C and D. They can be further divided into right and left or front and back riser groups, and by type of material.
    Swoop. 1) To dive down to a formation or individual in freefall. 2) To aggressively approach the landing area in order to produce a long, flat flare and an exciting landing.
    The Letter T
    TAF - Tandem Accelerated Freefall where the 1st 3 or 4 stages are done on tandem and then the AFF one on one jumps are done as per the standard AFF program.
    Tandem. Parachute jumps in which two skydivers, usually an instructor and student, share one parachute system. The student is in a separate harness that attaches to the front of the instructor's harness.
    Terminal velocity. The speed at which drag matches the pull of gravity, resulting in a constant fall rate. Typical terminal velocity for formation skydiving is in the 120 to 135 mile per hour range, but speeds as high as 300 miles per hour have been reached.
    Three ring. A parachute release mechanism that utilizes three rings of separate size in a mechanical advantage system. Invented by Bill
    Booth in the late 70s, the three ring release is almost universally considered the best cut away system available.
    Throw out. A deployment method in which the pilot chute is stowed in a pouch on the belly, leg of bottom of container.
    Toggles. Handles on the steering lines.
    Track. To assume a body position that creates a high forward speed. Used to approach or depart from other skydivers in freefall.
    TSO. Technical Standard Order. A technical standard that all American parachutes must meet before they can be marketed. Unless specifically
    exempted by the FAA, a parachute must have a TSO placard to be legal.
    Turn around load. When the aircraft does not shut down between loads, but lands and picks up skydivers for immediate departure.
    The Letters UV
    Uppers. The upper winds, or winds at exit altitude. The "uppers" are often much stronger and occasionally from a different direction than ground winds.
    USPA
    The United States Parachute Association is a non profit skydiver's organization. USPA offers guidance and assistance to skydivers in training, government relations, competition, and many other fields. Most drop zones require USPA membership of individual skydivers because such membership includes third party liability insurance.
    The Letter W
    Wave off. Prior to deployment a skydiver should make a clearly defined arm motion to indicate to others nearby that he is about to open his parachute. A good wave off is essential to the avoidance of deployment collisions.
    WDI. Wind drift indicator. A paper streamer thrown from the jump plane to estimate winds under canopy and determine the spot.
    Weights. Many lighter skydivers wear a weight vest to allow them to maintain a fast fall rate.
    Wuffo. Skydiver slang for people who don't jump, from "Wuffo you jump out of them planes?"
    Wind line. An imaginary line from the desired landing area, extending directly along the direction the wind is blowing.
    Winds aloft. See uppers.
    Wing loading. The ratio of weight born by a wing to its surface area. In the US, divide your exit weight in pounds by the square footage of
    the canopy.
    The Letter XYZ
    Zero-p. Common slang for a type of fabric relatively impermeable to air. The less air that flows through the fabric wing of a ram air parachute, the more efficiently it flies.
     
     

    By admin, in Safety,

    Canopy Flight Simulation for Education

    Skydiving requires an action to survive. Freeze, fight or flight are natural reactions to stress but they do not work for skydivers. There is very little time to think about what to do next when the ground is approaching fast. Hence, our response must be quick. We can separate a human reaction into three process: perception, assessment, and execution. These processes happen consecutively. The faster we complete them, the quicker our response is to the changing environment. Let's examine how education and training affects these processes.
    Perception is the process during which we become aware of information: we look at the altimeter to know the altitude, we look around to see if no other canopies are moving to collide with us, etc. Education and past experiences play a major role in a person's perception. We are not necessarily aware of what we look at. Education trains us to look for the right information in the right places. For example, if we do not look around after our canopy opens to see where the drop zone is, we will not turn to fly toward it. On the other hand, even if we see where the landing area is, we may not know how to detect if we can reach it. As a result, we may not make a turn to fly toward the landing area in time.
    Books and instructors tell students where to look and what to see, while videos show us examples. However, once students are in the air, they must make a conscious effort to look in the correct direction and focus on the right information: "It's landing time. The ground is moving very quickly. It should not move so quickly. Ohh... I must look at the horizon, I must not look directly underneath." The goal is to make proper perception a habit, because conscious effort is slow. Habits develop with practice, and practice takes time. A student has not yet developed habits and may forget to think about what to pay attention to, but help comes from the instructor over the radio: "Prepare for landing flare. Eyes on the horizon..." One does not develop a habit by taking a class, reading a book or watching a video. Instead, these sources supply knowledge that can be used during practice, which eventually leads to habit. Simulation of a situation, on the other hand, does help to develop a habit, in a safe environment.
    The emergency procedures that every jumper practices before every jump (you do, right?) is the example of a "simulation". In such "simulation" we create situations and responses ourselves. Another example of a "simulation" is hanging in a harness during a safety day. In this circumstance, an instructor creates an emergency situation for us. Dirt-dive is an example of a non-emergency "simulation". Airplane pilots take the concept of "simulation" further by using flight simulators (http://en.wikipedia.org/wiki/Flight_simulation). The military have used skydiving computer simulators (these are similar to flight simulators) for some time. Nowadays, computer parachute simulation software is available for everyone.
    The second process in our reaction sequence is assessment - making a decision about what the acquired facts mean. We look at the altimeter and it's 2000 feet. Nothing to be done just yet, or maybe we still have a problem with the canopy, or maybe we see that we are not making it to the landing area, etc. Education has the largest impact on the process of assessment. We are taught what actions are required in different situations. At the very beginning, all we need to do is to pick the right action from the proffered set of actions.
    Speed of the recall is important. Repetition is key for a quick recall. Taking a class, reading a book, or watching a video are good ways to refresh our memory (safety days help us do exactly that). The disadvantage of these methods is that they cover very limited number of situations and conditions. For example, we are told that to get back from a long spot we can use rear riser input, but that's only true for a certain ratio of your canopy forward speed and the speed of the wind. In some situations, we may have to use front risers or brakes. Now instead of a simple memory retrieval task, we have to do some reasoning. We may have all the knowledge to do the reasoning properly, but it's slow and error prone (time pressure and adrenalin rush do not help rational reasoning). Simulations offer an efficient way to condition memory by repetition. A computer simulation also allows for an infinite amount of situations with different conditions. It's easier to make a decision when we have already seen such a situation before.
    Execution is the process of acting on the chosen response. Muscle memory allows us to speed up this process. Instructors, books, or videos can not help this process. Muscle memory is developed by repeating an action... but we already know that simulation is good for that! Pulling the cut away and reserve handles while hanging in a training harness or before your reserve is due for a repack are good examples of muscle memory training: we feel how hard we need to pull the handles, what the proper motion of the hands are, etc. Computer simulation can help as well, but it is most effective with a special hardware, which is not yet available at a reasonable price.
    We have covered three processes that contribute to our reaction: perception, assessment, and execution. We repeat them over and over again. Every time we do something, a new set of conditions manifests itself. There is a dynamic and complex relationship between the situation and our responses to it. Instructors, books, and videos can only mention a very small set of examples. Traditional simulation methods (use of the imaginations or/and an instructor) are also quite limited. A computer simulation, however, provides real time feedback for all possible actions that we can exercise in the simulation. We can judge the correctness of our actions based on what happens next.
    Simulation has always been an essential part of skydiving education and training. Computer simulation takes this concept further and allows for even better results. We have seen how it can help us when other means of education and training are less efficient or can not help at all. One may ask: "How good must a "computer simulation" be to be used for training?". A similar question would be "How good must a picture be in a text book?" The answer is "As long as it (simulation or picture) reasonably illustrates the required concepts." No educational tool can or should be used by itself. The purpose of the tools is to make a student think, ask the right questions, and develop the correct responses.
    Given our limited attention span, it's always a compromise between focus on safety and focus on other things, especially for novice jumpers. The faster we get our habits and muscle memory developed, the safer our jumps become. This is why it's important to understand what tools are available to us, and what their limitations, advantages, and disadvantages are. In his book "The Parachute and its Pilot" Brian Germain phrased it this way "When we can acquire the right information, and access this data at the right time, we have a pretty good chance of walking away from sketchy situations." Our goal is "to acquire the right information." We can do this most efficiently when we understand what educational and training tools we have in our disposal: classes, book, videos, simulations, etc. The newest tool in the skydiver's toolbox is computer simulation software. This software greatly complements the other means of education and training. Which, in turn, will result in a safer and more enjoyable sport.
    Author Information:
    Alexander Shyrokov is the founder of Static Line Interactive, Inc.

    By admin, in Safety,

    Exit Separation Revisited

    Exit separation has become a point of contention at many DZ's lately. Years ago, when belly flying was the rule and the Cessna 182 was the aircraft at most DZ's, exit separation wasn't too much of a big deal - you gave the other group (if there was another group) some time and then you went. With the aircraft in popular use 15-20 years ago, it was hard to exit very quickly to begin with, and so the issue never came up very often.







    Bill von Novak started skydiving in 1991 at a small DZ in New York. Since then he has become an S+TA, an AFF, tandem and static line instructor, and has set two world records in large formation skydiving. He lives with his wife Amy in San Diego.


    Since then, several factors have conspired to make exit separation more of an issue. First off, there are more people freeflying. Freeflyers, especially head down groups, drift differently than belly flyers, and thus need different considerations when planning for exit separation. Faster canopies mean that people who open facing each other need more distance to deal with a potential collision. Large aircraft with big doors can hold several larger groups, and those groups can get out those big doors more quickly. Finally, GPS spotting has removed some of the delay between groups. It's rare to see people even check the spot before beginning their jam-up.
    I first became aware of this issue in 1994, when I started jumping at Brown Field in San Diego. We went through a series of aircraft as we grew, from Cessna 206's to King Airs to Beech-99's, none of which had GPS. In addition, we were less than a mile from the US-Mexico border, which meant our jump runs had to be east-west and our spots had to be dead on. Several instructors were "designated spotters" and we would argue over 100 yard differences in jump run offset and exit location. After a while we got pretty good at spotting.
    As our aircraft became larger, exit separation became more of an issue. We had a few close calls, and so we agreed to start allowing more space between groups. At first it was essentially trial and error - we would leave some amount of time (10 seconds or so) between groups and increase that time whenever someone felt they were too close to someone else. After a while, we began to get a feel for how much time was required. We knew that if the upper winds were strong and the plane was just creeping along the ground, we had to leave more time. We also knew that if we let the freeflyers get out first, we had a problem almost every time. We ended up with a system that worked for us, and had essentially no problems with collisions or close calls after that.
    During this time I was also traveling in the summers to different boogies and I noticed a wide variety of exit separation techniques. By far the most common technique was some amount of fixed time - the next group would pause, then climb out and go, without knowing what the upper winds were doing or what the spot was. The next most common technique was similar but they added a "leave more time if it's windy" clause to their delay. There was also a class of jumpers who looked out the door to tell how much separation to leave; these jumpers either looked at angle of the departing group or the ground to tell how much space to leave.
    This got me thinking. What really works and what doesn't? I tried a few methods on my own, from the "45 degree" method to a purely ground-based method. After some experiments, a group of skydivers collaborated via email and internet and came up with the actual math behind separation, the physics that determines how far the center of group A will be from the center of group B after they open. But before diving into the math, there are a few basic concepts to cover.
    What we care about. When we're talking about separation at opening time, we don't really care about where we are in relationship to the plane or even the ground - what we care about is how far we will be in the air horizontally from the next group that opens. So for our purposes, the airplane and the ground don't really matter, and someone watching from either of those places may not get the same "picture" of things that we get. (Of course, we do care about our relationship to the ground when it comes to spotting and landing on the DZ, but that's a separate issue.)

    How we fall. In most freefall (tracking dives and wingsuits excepted) we fall essentially straight down with respect to the air. If there's wind, the wind blows us at whatever speed it's blowing. If the wind is doing 30kts at altitude, a group of skydivers will be doing 30kts as they drift with the wind. It's also important to realize how your trajectory changes after you open. At a freefall speed of 100kts, a 30kt wind will slightly deflect your trajectory, because it's a small fraction of your total speed. Once under canopy and descending at 10kts, it will deflect your trajectory a tremendous amount, since it is now a very large part of your speed. Of course, under canopy you have much more control over your own horizontal speed, and the winds may add or subtract from your canopy's groundspeed depending on the direction you are facing.

    Speeds. When discussing speeds, it's important to define units. There is feet per second, which is very useful for people who are trying to figure out how far they want to be from another group. At 100 feet per second, 10 seconds gives you 1000 feet, which is about as easy as it gets. You may also hear the terms indicated airspeed, true airspeed, and groundspeed, in both knots and miles an hour. These can all be converted back and forth as needed . Now that all that's out of the way, the math is pretty simple. The distance you will get between group centers is the speed of the aircraft plus the speed of the winds at opening altitude, multiplied by the time you leave between groups. That's it. So if the aircraft is flying into the wind doing 80 knots per its GPS, and the winds at opening altitude are 10 knots from the same direction, and you are waiting 10 seconds between groups, you are going to get (80+10 = 90 kts, which is 153 feet per second) 1530 feet between groups.
    It gets a little more complicated when the winds are not from the same directions. If the winds at opening altitude are opposite jump run, you have to subtract them rather than add them. If the winds at opening altitude are from the side, it's the same as zero winds at opening altitude when it comes to separation.
    If you put these equations into a spreadsheet and play with the numbers, some basic patterns emerge. If the headwinds at altitude are strong you have to leave more time. If the plane is slow (i.e. it's indicated airspeed on jump run is low) you have to leave more time. If the winds at opening altitude are strong as well, and from the same direction, you can safely leave less time. (Or, preferably, just leave the same amount of time and you'll end up with even more separation.) If the winds at opening altitude are opposite from jump run, that's the worst case, and you have to leave even more time.
    Some people have a problem visualizing how winds at opening altitude can possibly cause them trouble if they leave enough distance on exit. The question is usually phrased as "don't all jumpers follow the same path out of the plane?" And they definitely do. To visualize why this can still cause you problems, take a look at the separation diagram shown below.


    Drawing showing exit separations
    In the first drawing, there is no wind after exit, and the first group breaks off, tracks, opens, and flies their canopies away from the center for the first few seconds, which is what they should be doing on most formation skydives. (After that, it's a good idea to turn away from line of flight once you're sure you are clear of others in your group.) The second group arrives 10-15 seconds later, shortly after the first group has opened their parachutes, with some room to spare.
    The second drawing shows what happens when there are winds are the same all the way down. Notice that the "cone" caused by the breakoff and the canopy flight has shifted strongly to the right. This is because (as mentioned before) once their parachutes are open, the wind affects their trajectory more strongly. As with the first example, it is assumed that everyone flies away from the center for the first few moments. That means the jumper flying into the wind makes no progress and comes straight down, while the jumper flying downwind gets a boost in groundspeed..
    The third drawing shows where you can run in to problems. In this drawing, the winds after exit are from the opposite direction. You get the same skewing of the cone, but now the edge of the cone is getting dangerously close to the trajectory of the next group. This is a case where the same separation at exit led to trouble because of opposite winds at opening altitude.
    This leads naturally to the question "how much separation do you really need?" That depends on the group. 1000 feet should probably be an absolute minimum for any belly formation skydiving. That means that two four-ways can exit, fall straight down the pipe, track 300 feet from center on breakoff, and then still have 300 feet to deal with avoiding a potential collision after opening. With the speeds of today's canopies, that's a bare minimum. If the group size grows to two 10-ways, 2000 feet might be a wiser separation. If a low-time RW group backslides a bit, again, 1500 feet might be needed to be clear of them at opening time.
    So how does a jumper who doesn't want to carry around a calculator figure out how much time to leave between groups? One very simple way is to just look out of the plane and wait until it has covered 1000 feet, then go. This method, originally suggested by Skratch Garrison, takes much of the figuring out of exit separation. It can be hard to determine how far 1000 feet is on the ground, but fortunately most DZ's come with a handy ruler - a runway. A 3000 foot runway allows you to put 3 groups out along its length with a bit of margin thrown in. This method also has the tremendous advantage that it requires people to look out the door, and that means they are more likely to see traffic, high canopies or clouds that could pose a hazard to their skydive.
    Another simple way is time-based. There are several tricks you can use to determine how long to wait. One common one is to always leave at least 7 seconds, then if the upper winds are strong divide them by 2 and wait that number of seconds. (Faster aircraft sometimes use divide by 3.) So if the winds are 30kts you wait 15 seconds between groups. This technique uses some math but isn't too bad.
    A third technique that seems to be popular for some reason is the 45 degree method. In this method, jumpers wait until the previous group passes through an imaginary 45 degree line before they exit. The problem with this method is that the jumpers never pass through that 45 degree angle, or pass through it so quickly (under 1 second) that it's not useful for determining separation. The numbers confirm this. What you see out the door depends purely on speed of the aircraft, fallrate of the jumpers and type of exit. If the plane is going slower than freefall speed, the group may start out above the 45 degree line, but will drop below the line in less than a second and never rise above it again. If the plane is going faster than freefall speed (which is rare) the jumpers stay above the line and never cross it at all. A good head-down exit will tend to move jumpers lower in the picture. Winds will not affect the picture; an exit in 5kt uppers looks the same as an exit in 50kt uppers.
    There has been some friction over this issue. The 45 degree method has a lot of supporters because it's so simple and makes a sort of intuitive sense. Beyond that, it actually seems to work for some people - although it's likely that the extra time it takes to locate and stare at the previous group has something to do with the reason the next group usually leaves enough time. To show that this doesn't work, two cameras were fixed at a 45 degree angle and mounted on a boom outside an Otter's door (see pictures below.) Pictures and video of several jump runs both into the wind and downwind were taken and magnified to determine how close each group was to the imaginary 45 degree line, which was essentially the center of the images. The pictures confirmed the basic problems of the 45 degree rule. RW groups, falling a little faster than the aircraft, never quite passed behind the 45 degree line. Freeflyers, going much faster than the aircraft, stayed well below the 45 degree line for as long as they were visible in the stills (about 30 seconds.)










    Some version of the 45 degree method may work for some people. It may be that the simple act of looking out the door delays them enough, or their subconscious may see the group moving slowly along the ground (because the aircraft's groundspeed is low) and send a warning message to the rest of their brain - "hey, hold up a minute." But waiting for a true 45 degree angle simply does not work.
    Another issue that has become more important lately is exit order. Some places still put freeflyers out first, and that doesn't make much sense. In 30kt uppers, a belly flyer who leaves 10 seconds and gets out after freeflyer will open 100 feet from him, but if the belly flyer goes first and the freeflyer leaves the same time he will open 2200 feet from the freeflyer. RW groups, since they are in freefall longer, drift farther downwind before opening. It seems like a no-brainer to choose an exit order that used this to your advantage and increased, rather than decreased, separation distances. You can certainly wait 20 seconds after the freefly groups before the belly groups exit if there is some other reason why the freeflyers have to exit first, but at most DZ's it's hard to ensure that 20 seconds, especially since waiting so long almost guarantees long spots or a goaround.
    Below are two diagrams that show how exit order can affect separation.

    Belly out first diagram

    Freefly out first diagram
    One reason given at DZ's to explain a backwards exit order is that freeflyers open sooner and therefore are beginning to descend before the next group gets there. Bryan Burke of Skydive Arizona has pointed out that you simply cannot trust vertical separation - one premature deployment or malfunction and all that vertical separation is gone. Even during a normal skydive, when you add up altimeter error, pull timing and snivel distance, you can easily get a jumper opening 1000 feet from where he expected to be open. In fact, Bryan points out that at Skydive Arizona, the primary reason high pullers get out last is not for separation but rather because they are the ones that can make it back from a bad spot.
    Every drop zone is going to have a different set of rules and a different approach to exit order. Some work well, some don't work as well. Jumpers have to understand the factors that can reduce group separation so they can make informed decisions about when they want to exit and what kind of exit orders they are comfortable with.

    By admin, in Safety,

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