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Troubleshooting Your Harness Parachute System

By Betty Pfeiffer 1-99

Introduction

In the early 80’s during my very limited dabbling in competition, I would hear Rich Pfeiffer psyche-out the competition by declaring "I have a parachute and I am not afraid to use it so you had better not get in my way!" With over 1000 skydives and several skydiving championships under his belt, everyone knew he was serious.

At that time parachutes were a fairly new addition to hang glider safety gear and pilots would wear them with a false sense of security. Many thought that they could get away with trying anything they wanted in a hang glider because they had a parachute that would save them.

Today we know that pilots are sometimes saved by their parachutes, but not always.

In this article I will address the issues of parachute/harness/deployment system compatibility, system strength requirements and routing/rigging issues.

For a clear understanding of when and how to use your parachute please refer to the following articles that appeared in Hang Gliding Magazine: :Lookout, Lookout Lookout: How to Save Your Life (Jan. 1998), Basic Parachute for Pilots of All Stages (June 95), Misconceptions About Parachutes (July 93), The Ballistic Controversy (1994), and Parachute Quiz (August 93).

System Compatibility: Pilots Today must be Pro-active…Know your equipment!

In order to open your parachute you must be able to get it out of your parachute container. The ease with which this can be achieved is determined by handle location, handle length, safety lock design, flap closure arrangement, and parachute location relative to the handle.

The best way to determine if your arrangement is adequate is to suspend yourself from a rope, hang in flying position and pull the handle of your parachute. If the safety pins release smoothly and your parachute container opens, your system is probably good.

Try to make it fail.

It is just as important to know how your container will NOT open as it is to know how it will. Try to open your parachute container by pulling the handle in many different directions and seeing what happens.

The chart below reflects some common parachute container problems:

Problem Possible Cause Remedy
Cannot grab the parachute handle Flimsey handle is caught on Velcro.
Or
Handle loop is too small
Or
Handle is in a bad location
Add stiffener to handle and pre-flight carefully.
Have handle replaced by qualified person.
Have parachute container moved to a more suitable location.
Difficulty opening velcroed parachute container Velcro is too wide. Cover a portion of the Velcro hook to achieve desired Velcro strength. Remember that the longer Velcro sits hooked together the more it grips and the harder it is to pull apart.
Parachute container Velcro is buckling when you pull the handle instead of peeling open. Have parachute container secured better to the harness
Or
Insert stiffener between back of Velcro on flap and the harness material. This is done only on the edge of the container with the grommets.
You pull the handle but your safety locks do not release. Your parachute handle is too short for your harness container design

Or

Your safety locks are in a poor location for your container design

Or

The grommets on your parachute container are too far apart or too close for the location of the safety locks on your handle.

Or

Your parachute is too small for your container and slides down too much while you are in an upright position.

Or

You have clevis pins that do not rotate properly for an easy release. Note: Clevis pins are very dangerous for the following reasons: They can bind instead of releasing properly if pulled in the wrong direction. In time they have a tendency to flare at the tips which can keep them from releasing. They can bend easily which can cause many problems. Some have very sharp tips that can puncture your parachute container.

Or

The loop holding your pin is too tight

Have a longer handle installed on your parachute container by a qualified person. Note: There were cases in Europe where pilots had "home made" handles that actually ripped off during attempted parachute deployments.

Have your safety locks relocated by a qualified person.

 


Have your grommets re located by a qualified person.

Add foam or other filler in the bottom of your parachute container to help hold the parachute in the proper position. Make sure the filler does not interfere with any aspect of the deployment process.

Or

Have you parachute container made smaller.


Replace clevis pin with a standard curved safety pin.

 

 

 

 

Replace loop. Note: Over time your bungee loops can loose their elasticity or your rubber loops can tear.

 

 

 

 

Your parachute is placed in the harness the wrong way. Flip the parachute over with the handle towards the outside of the container and try again.
Your safety locks keep slipping out of their holders Loop is too large If you have a bungee with a knot in it move the knot to make the bungee smaller or add washers to make the loop smaller. If you have a different system, reduce the size of the loop or replace the loop.
You pull the handle but the parachute will not come out of the container. You are pulling in the wrong direction.


Or

Your parachute container is poorly shaped or poorly placed for your deployment bag.

Try peeling the Velcro downward with the handle then extracting the parachute.

 

Replace the parachute container or deployment bag with the appropriate shape.

The importance of extracting your parachute cannot be over emphasized. Several years ago there was a pilot who found himself tumbling violently. He went for his parachute but could not get it out of his container. As he continued tumbling he remembered hearing about pilot who tumbled, righted herself and was able to fly the glider down. He then went back to the control bar hoping to regain control, but he kept tumbling. At this point he decided to go for his parachute again. By the time he finally got it out he was too low for a full deployment.

The big issue here is why couldn’t he get the parachute out of his container?

This pilot had attended a parachute clinic 6 years before the incident at which time he did practice deploying his parachute. Two years before the incident he had purchased a new harness and parachute. He never practiced getting his parachute out of his new harness. He assumed the same direction of pull he used on his old system would work on his new harness. This was a big mistake.

 

VERY IMPORTANT:

Anytime you change your harness, parachute, deployment bag, and gain or lose weight, suffer an arm or shoulder injury be sure to practice getting your parachute out! Make sure all your safety system components are compatible. Practice extracting your parachute from your harness container while suspended in a prone position and a seated position. Practicing parachute extraction does NOT mean you have to re-pack your parachute, just get it out of your harness’s container.

Strength issues

Your safety system includes your parachute, bridle, paraswivel, Carabiner, hang straps and harness. It is only as strong as the weakest link.

How strong does your safety system really need to be?

Your system needs to be strong enough to withstand the worst possible scenario. That may be a cross bar failure where your wings fold up or even a situation where you are separated from your glider and in freefall.

If you have a high performance glider you can conceivably reach speeds upwards of 90 mph. Your safety system needs to withstand those forces without failure.

In order to determine your personal strength requirements we will assume a maximum parachute-opening load of 5 g’s after freefalling 7 seconds. Multiply your total launch weight (total weight of your hang glider, harness, parachute, clothed body weight, water, instruments, roll of toilet paper and anything else you fly with) by 5. Multiply that number by a safety factor of 2. The final number tells you how strong the weakest link in your system must be.

2(Launch weight * 5) = strength needed for your weakest link.

Remember that safety systems can lose strength due to environmental damage i.e. rust, abrasion, exposure to UV, extremely wet climates, extremely dry climates, freezing and thawing etc.

How can you identify inadequate construction?

Examine your harness. Feel for continuous webbing structure or consult the manufacturer about the harness strength. Inspect all the stitching for frayed or pulled stitches. Be wary of worn or faded areas in your harness. Look at the bridle routing and your bridle attachment point to your harness. Pay special attention to your harness lines or areas that rub. Consult the following chart if you identify problems.

Problem Possible cause Remedy
Too few stitches holding a structral component of the harness Sewing machine operator and final inspector goofed.

Or

Harness design inadequate

Or

Heavy weight thread was used with the proper stitch pattern and stitch size but it just looks weak to the untrained eye.

Return harness to be sewed properly by the manufacturer

 

Have qualified person reinforce the weak area.

None needed

Stitching coming undone Sewn in a bad direction relative to the forces being applied in use.

Or

Abrasion has weakened the stitching.

Have it re-sewn by a qualified person using the proper stitch pattern and thread.

Re-sew

Parachute container is falling off Stitching has come undone

Or

parachute container has torn

Re-sew
Parachute container keeps opening Weak Velcro

Or

Stitching on Velcro has come off

Or

Harness does not fit properly

 

Or

Harness container is the wrong size for the parachute

Or Harness parachute container is the wrong shape for your parachute

Or

Bridle is pulled too tightly into the parachute container

Replace Velcro

Re-sew

 

 

Try loosening the leg straps or adjusting the harness lines a different way.

 

Adjust or replace your parachute container

 

Replace deployment bag or container

 

 

Allow enough slack in the bridle before it enters the parachute container to accommodate the harness stretch when your body weight loads it.

Parachute handle is not accessible with aero tow bridle attached Detach or re-route the bridle after the tow Use a bungee cord to pull the bridle away from parachute interference or consider a different handle placement on you parachute container (consult your harness manufacturer.
Zipper on legs of enclosed style harness will not zip all the way up

 

 

 

 

 

 

 

Your arm is too short to pull the length of the zipper.

Or

You are looking down at the zipper forcing the zipper to stay wide open at the top.

Or

Your leg straps are too tight

Grab the cord to make a shorter distance to pull.

 


Arch your legs up as you zip to allow the complete length of the zipper to close.

 

Loosen your leg straps.

Difficulty in zipping your harness up Your harness zipper has been damaged due to excessive strain when you fold it for storage.

Your pant legs or shoe laces are getting caught in the zipper

Your harness is not adjusted properly

The extra webbing from your adjustable leg loops is getting caught in the zipper

Fold your harness with the least amount of bend in the zipper. You try keeping the zipper open during storage. If you see damage in the coil or teeth , you may need to replace the zipper

Wear tighter clothing.

Tie your shoes with short laces behind your heel or cover up your shoelaces to keep them from hanging.

Loosen the leg straps. If you have them too tight they can be holding the zipper open.

Tuck the excess leg strap webbing into the leg pad or secure it in other ways.

Your jacket style zipper opens during flight Your zipper is not properly inserted into the slider Make sure your zipper is inserted all the way into the slider before zipping down.
Your leg strap buckles keep slipping Webbing is too slippery for the buckle to grip.

Or

Buckle is attached the wrong direction.

Or

The direction of pressure on the buckle allows it to slide

Have qualified person sew on additional layers of webbing

Have the buckle re-attached properly.

 

Tack the strap in place by sewing a x at the proper length.

Other problems to avoid    
Accidental deployments

 

Body entanglement inside the harness

 

 

Harness gets caught on cables

Safety pins not in place

Parachute handle is located too close to the zipper pull cords

Freshly packed parachute has not compressed and pushes the container open.

Foot gets caught on rope or bungee systems inside the harness

Instruments or other options are located on the side of the harness.

Preflight your safety pins before each launch

Change your parachute container to locate handle in a better position

Sit on your parachute after each repack to squash to air out. Do a knee test before you fly. Be sure Velcro is secure.

Have a protective sleeve sewn to cover places of potential entanglement

Move the option off the side of your harness

Parachute Bridle Routing

Sometimes we know intellectually that something bad can happen, but we are confident that it will never happen to us. Sometimes we can see a potential problem in a system, but since it never seemed to be an issue in real life situations, we minimize the danger.

Sadly last year we learned an important lesson that cost one pilot his life. That lesson is this: The way you have your parachute bridle attached to your harness or routed from your harness can kill you.

We strongly recommend your parachute bridle is attached directly to your Carabiner, routed down the outside of your harness and into your parachute container.

Bridle problems

Problem Possible cause Remedy
Bridle has slipped out of the container. Bridle has a large loop where it comes out of the parachute container Attach Velcro loops or a Velcro strip to the harness to secure the bridle.
Bridle looks fuzzy where it goes into parachute container Velcro hook damage. Replace bridle with a new one that has a protective cover.
Bridle keeps wearing out at the Carabiner Friction from rubbing against harness lines Slide your bridle up your Carabiner opposite the gate, and secure it with a rubber tube, bungee or other method.
Parachute opening force is transferred to the pilot before it goes to the broken glider. Bridle is sandwiched inside the cover of the mains on your harness and the weak stitching does not release properly.
Or
Bridle is routed inside the harness then up to the Carabiner
Or
Bridle is attached to the harness at the hip
Or
Bridle is attached to a single or double loop on the back or shoulders.
Route your bridle on the outside of the harness up to the Carabiner. Be sure to have velcros or staged attachment points so your bridle is snug to your harness.

The last item on the chart is extremely important. When the pilot is in between the parachute and the wreckage this is what can happen. The force of the parachute opening is transferred down the parachute lines through the paraswivel, down the bridle through the pilots harness to the Carabiner and finally to the wreckage. When the parachute opens the pilot will be jerked in the direction of the parachute. If there is anything in the way (tubing, control bars, cables, sail) the pilot can risk broken bones or snapped extremities including breaking his or her neck or back.

Even if the parachute opens without injuring the pilot, the pilot will be descending with the wreckage at the same level or even slightly below him/her. Since broken gliders can be extremely erratic and violent, this again increases the pilots risk of injury.

The conventional parachute bridle attachment at the Carabiner allows the opening forces to be absorbed by the bridle, and transferred via Carabiner to the wreckage and then via hang strap, to the pilot’s harness. A pilot who is descending below the wreckage (if possible) reduces the risk of injury from flailing wreckage.

Please note: damaged gliders can behave very violently even with the parachute open. The argument for having the pilot above the wreckage is that the pilot can use the wreckage to decelerate during impact. One argument against that approach is the possibility of becoming impaled on broken parts. The bottom line is this: there is no one perfect way to route the bridle that works best in all possible situations. The best we can do is to look at the situations that have occurred with similar performance hang gliders, and try to decrease our risk accordingly. We believe a bridle attachment to the Carabiner that does not include the harness is the best arrangement for most situations.

As hang gliders continue to develop and we continue to analyze parachute deployments, we may find that a different approach to parachute bridle routing or parachute deployment systems is beneficial to hang glider safety. I believe it is your responsibility to keep up with new developments. Remember different is not always better. Sometimes solving one problem can create a host of new problems. Evaluate each change with a critical eye! Remember it is your life we are talking about…

Fly Safely.

This article was inspired by problems we saw while doing parachute clinics around the country. I would especially like to thank members of Maryland Hang Gliding Association, Roanoke Hang Glider Pilots, Rouge Valley Hang Gliding Club, Sky Sports Aero Tow Club INC. of Whitewater WI, San Diego HG & PG Association, Orange County Hang Glider pilots, and AZ , TX, FL, MI Hang glider pilots who attended clinics. In addition I would like to thank all the High Energy Sports dealers and customers who have passed on their words of wisdom in solving harness problems.