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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.
A Good Canopy
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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
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 controllability 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.
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