Can you fall out of a properly fastened harness?
by Jan MeyerThere have been several fatalities of people falling out of a harness. These were either jumpers with unfastened chest straps or suicides.
Today's harnesses have a split saddle. This design has a piece of webbing that wraps around each leg to form leg straps. Each leg strap is attached to the main lift webbing. There is no load bearing attachment between the leg straps.
This design entered the sport parachuting market in the late 1970's.
On June 5, 1983 a jumper fell partially out of his rig. He was involved in a CRW wrap. After the cutaway, his foot momentarily hung up on the other guy's canopy. He was upside down. He shook loose of the canopy and that is when he fell out (backwards) of his harness. The leg straps were caught around his knees. The horizontals were up under his armpits. The jumper pulled his reserve and fortunately landed safely in water.
The rig he had was a Racer. The Racer at that time had adjustable side horizontals (as did most rigs of that era). He demonstrated his position later for JumpShack.
In early 2002, a tandem passenger almost fell out backwards of her harness (Sigma tandem). The harness was NOT properly adjusted. The Sigma tandem harness has a horizontal back strap. The purpose of this strap is to keep the person from falling out backwards. FMI see Relative Workshop Bulletin
Harnesses, Crossbow (left) and Thunderbow (right) in the 60s and 70s had a horizontal back strap very similar to the one in the Sigma tandem harness.
Other harnesses had a sling. This prevented the leg straps from dropping down to your knees.
On most of today's rigs there is no separate horizontal back strap. The lower part of the main pack tray provides the function of 'preventing a jumper from falling out backwards'.
In the 1990's rigs have become very small in relation to a jumper's body. Many people jump articulated harnesses.
On articulated harnesses and shorter containers the bottom of the main pack tray might be high - above the waist of a jumper. An example is on the cover of Jan 2002 Skydiving. The jumper in red, shown to the right in a Craig O'Brien photograph, has a rig that looks like he could fall out backwards under the right conditions. If that jumper had a hard, premature main opening right then - it looks like it is possible for him to fall out.
The two jumpers above are from an advertisement for Mirage in the March 2002 Skydiving magazine. The jumper on the left has his right leg strap down to his mid thigh region. It is not clear were his left leg strap is. The jumper on the right can slip out of that harness if she had a premature deployment.
These jumpers could fall out backwards if they had a premature deployment in that position. This problem is NOT unique to Mirage. All harnesses made today have this problem. These pictures were handy.
On articulated harnesses, the angle between the horizontals and leg straps can be quite large.
With the main out of the pack tray and your leg and chest straps fastened as you have them for a jump, try to back out of your rig. You'll have to bend at the waist and pull the reserve up, over your head. And you might have to 'help' the leg straps move towards your knees. This little bit of help would be provided by a premature opening on a real jump.
The question you want to answer is - can I fall out backwards?? The degree of difficulty is not important in this informal test.
Little bungy cross connector between leg straps
Please try this little experiment.
What to do about this
If you can easily extract yourself from your rig in this manner, contact the harness and container manufacturer. Do not do sitfly positions until you have a rig you cannot fall out backwards. The falling out hazard is greatest in a sitfly position. Not every combination of person and rig size will have a falling out problem. The manufacturerer should be the one to design and add a horizontal back strap.
A solution: I had a rigger make a connector for me. It is a piece of webbing with loops at each end. The loops slide over each of the leg straps. It is pulled up all the way to the top of the leg strap in back. The overall length should be such that the tension in the strap is snug when your leg straps are tightened for a jump. The loops are slightly smaller than the width of the leg straps so that it can stay in place without any additional tacking or rigging. I have been using this for a few years now.
In the pic, the red lines are a conceptual representation of stitching. It has no resemblance to the actual stitch pattern.
Overall Length of finished strap = the distance across your buttocks between the outside edges of the leg straps where you want the strap to float.
Mine sits at the top of the leg straps. I have a Racer without hip rings. It crosses my butt at the top of the curvy part of the butt - sort of like the RWS pic of the tandem horizontal strap.
The Sewn length of the loops = slightly smaller than the width of the leg strap where you want the strap to float. Slightly smaller means 1/4 to 1/2 inch.
My leg straps are not tapered. For tapered leg straps you might want to taper the loop too. You should still be able to slide the loops over the wider parts of the leg strap with a little bit of squishing. (Does that make sense?) You want the loop to be slightly smaller so that it stays in place without any tacking. Tacking would probably break after a number of jumps. My strap stays in place. I do feel pressure from it on openings.
I think that generic sizes can be made that will work for most people. The strap may sit in a different place tho. It is probably better to measure what you need on a rig/person basis. I will do this at Perris this weekend for anyone that wants one. I'll get Ziggy or someone to make them. I do not know the cost or turn time. You can have any color as long as it is black. ;) I'm sure a MFG can get you color coordinated.
For personal rigs, used primarily by one person, there is no need to have an adjustable strap.
© 2004 by Jan Meyer. All Rights Reserved
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