Sep 23, 2001, 10:01 PM
Post #1 of 16
I've seen people shooting accuracy sinking in on final approach with half brakes, and not coming back to full glide before landing. I know that's a nice, slow way to approach for accuracy, but on my student training, I was always told to be at full glide for the last hundred feet or so, to have enough speed for a full flare. So what's the correct way to sink in? I'd hate to find myself in a tight off-DZ landing(though there's not much around my home DZ except for miles of corn, but still) and accidentally collapse my canopy when I want to flare, or something like that. Although I guess I just answered part of my own question, get to know the way my canopy reacts at different speeds and inputs... but is there a "correct" procedure for this type of approach?
I fly a Triathlon loaded at just a tad over 1:1, by the way.
Each canopy weighted down at diffent Pounds per squar foot will all react differently. also how long your control lines are too will affect this. this is something that all peeps should try up high is to try to completely stall your chute. that way when you need to do a tight accuracy drop down if you are off airport you will know how far is too damn far.
this was taught to me during my AFF and during my consol jumps before my A. I also thought making an accuracy approach is part of the new A license program.
try it out....but do it up high so just in case it doesnt re-inflate you can go to Plan-b
If what you want is to land you heel on a 3cm target, then sinking the canopy from 50 feet is for you! make sure you aim for a nice air inflated tuffet though, as it may hurt otherwise!
Remember : the guys (and gals of course) who do hard core accuracy fly canopies designed for that purpose only: they will keep on flying (if you want to call it flying) even while going straight down, and even slighly backwards (having never flown one, I am speaking completely though my hat on this one).
they won't fly backwards, unless of course the wind is high enough. But, yes, a true accuracy approach entails "sinking" is down. those canopies open like crap, steer like crap, and land like crap, but if you want to put your spiked heal on a quarter, they'll do that. I speak from experience (although I was able to hit the target, not the center though)
it is scarry.... ancedotal story: the DZ where I learned (cessna 182) you had to learn to spot, it was a pretty tight DZ with weird winds. Any way, there was a guy visiting from a "green light" DZ - he was most experienced on the load, so he was going to spot. Pilot says you can have the door -- he opens it gets out and goes, everyone else waited the mile and gave the left hand correction needed :) it was pretty funny (they did go out and pick his humbled butt up though)
At the Richmond Boogie, one of the regulars at our DZ was trying to back his canopy into a small space. He was about 50-100' above the CONCRETE in front of the hanger when his canopy collapsed and reinflated quickly. Damn!! I saw him doing that (from straight below) and thought...RUN!!!
Your instructors taught you the full glide to full flare landing because that approach works with all canopies. A full glide to full flare approach also produces the fewest injuries, which is what they are really aiming for.
Yes, it is a good habit to practice flying in deep brakes, as long as you practice up high. Some smaller, faster, fashionable canopies will stall and fold up in a deep stall, not something you want to learn at 40 feet above the bowl!
Accuracy competitors jump specially designed canopies. Accuracy competition is dominated by two canopies: the Jalbert Para-Foil built by North American Aerodynamics and the Challenger Classic series built by John Eiff and New England Parachute Company. These competition canopies have extra vents and extra stabilizers to keep them stable on the edge of the stall. Few canopies generate much lift while they are on the edge of a stall, so accuracy competitors substitute more fabric to soften their landings. Most of them load their specialized canopies at 0.7 pounds per square foot, less than half the wing loading you need to win a pond swooping contest. These huge canopies also pack huge, so you won't win any style points with your big rig.
You have also noticed that they only approach in deep brakes when they are going to land in the pea gravel bowl. Too many hard landings forced accuracy competitors to invent a target even softer than a pea gravel bowl. Now most accuracy competitions are done onto a giant air bag called a tuffet.
The only way your bones will survive hundreds of hard core accuracy landings is to land on a tuffet. To find tuffets, you have to train at the same dropzones as hard core accuracy competitors, ie. Raeford in the Carolinas.
I'm pretty sure Ellington (CPI) in Ct has a tuffet -- Marylou practices there most often. If you keep the peas turned over they aren't to bad, but a lot of work. I landed at the edge of the pit once, about broke myself in half
Ok, thanks everyone. I read somewhere that the Triathlon is good for occasional accuracy, since it's 7-cell...? I guess my best course of action would be to practice slow flight up high to find out where exactly I collapse my canopy, and if I do ever need to sink into someone's backyard, get my ass ready to PLF...
OK, nobody answered the way I would have, so here is the basic technique for target accuracy; technically, stand-up target accuracy:
A parachute like a Triathalon is perfectly suitable for this approach, so long as you don't get too steep with it. I will describe the technique starting from the time you turn your main onto final, somewhere between 500 and 300 feet.
First, turn your parachute onto final, straight downwind of your desired target. Generally, accuracy approaches are flown down at about a 45 degree angle or slightly steeper, but you might want to take it out a bit farther if you are just working on landing in a general area. Either way, you should pick your exact desired landing spot on every jump; not just be happy to land "near the beer line". Once inline with the target, look down and out at the target; lock your eyes on it. Some people keep their feet and knees together and look right between their feet; this is what I call "using a gunsight". Pull your brakes down to about shoulder level and let the canopy settle into a sink. This will take a couple of seconds so give it a chance. Once settled, the new angle of attack will be steeper. Look and see if the target is moving towards you or away from you. If it is getting closer, input a couple of inches more brake; if it is moving away, let up a couple of inches until you are looking down at 45 degrees again. Never "saw the lines", or make big over-corrections; you will never know your true angle of attack until the parachute settles again. Try and maintain that 45 degree glidepath and aim for a point about five feet past your target. Doing that, right before you fly over the target at about eight feet, go ahead and slowly flare your parachute the rest of the way. Do this and you will sink straight down that last little bit. Keep your knees bent and stick your landing. Next, turn, salute the crowd, then move out smartly. Do not stop your parachute over the target if you are still at 20 feet! Do not do a dynamic flare; just stop your forward movement. If you are too high, overfly it and then stop it whenever you get about five feet above the ground. Work on your approach the following jumps until you get your glidepath "sight picture" worked out.
I have had the opportunity to do many demonstration parachute jumps as a member of two parachute teams (GB and 20th SFG). I learned the RIGHT way to do demos at Golden Knights tryouts in 1990. Being very-still in the harness and making tiny little corrections yields the best results for both stand-up as well as competition accuracy. Competition accuracy jumpers (like my wife), can get away with much steeper approaches because of the tuffet. Ours at Raeford is actually foam filled as opposed to the european blow-up variety. I have shut a Sharp Chuter down at 15 feet and dropped straight down onto the target successfully, but would not recommend doing that on a no-wind day under that Triathalon. It is best to practice even stand-up accuracy over pea gravel pits and tuffets, so that you don't pile in working on your technique. Accuracy is actually quite fun and rewarding when done correctly, so give it a whirl.
You can sink in the majority of lightly-loaded mains, but you must be careful not to stall smaller parachutes at an altitude you cannot walk away from. The higher the wingload, the less-steep you should make your approach.
Doing that, right before you fly over the target at about eight feet, go ahead and slowly flare your parachute the rest of the way...
That's were I screwed up!! Im coming out of my 'sink' higher that I want to , trying to get back to full flight before flair time. Almost broke my leg this weekend sinking in too low and release back to death speed right before hitting the ground...
Im thinking (now that you've kick started my brain) sink in at "not so steep" of an angle and save the right amount of flare for the end. LIGHTBULB - Thx!