Why are chest straps the way they are?!?

[pchapman 261]

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Weren't there some rigs built in the 70's that sported velcro chest straps?

I wasn't around at the time but I've only seen that done for a few harnesses using a belly mount, so that there's a reserve container in front. The container holds the main lift webs in place, although I suppose high structural strength only exists in the cross connector between the reserve risers.

[erdnarob 1]

Well, you know that you can design a fool proof device and be sure that there will be somebody to find the way to screw it. Yes you can misroute a chest strap the following way. You thread the free end of the chest strap between the frame of the adaptor and the friction sliding bar concave side first and then thread it around the convex side of the sliding bar and back to the elastic keeper. This is one of my trick when a new jumpmaster or a novice is doing an exam on the gear inspection. I take a rig and put up to 7 "mistakes" in it and the candidate has to find them all. As you said, how can we misroute a chest strap then since what I have described above looks "normal" the candidate very often misses it.

Learn from others mistakes, you will never live long enough to make them all.

[erdnarob 1]

For sure those extra folds at the end of chest strap and leg strap as well are important and a rig without that should be grounded. This is the last barrier before losing everything. But there is a lot of play before those extra folds come against the adaptor and if it happens there is a risk to fall out of the harness at opening. I can see that in case of an unstable opening the adaptor can suffer a high load which is relatively low in case of a normal opening.

Learn from others mistakes, you will never live long enough to make them all.

[erdnarob 1]

Thank you Gary. Amazing on the picture; the free end of the chest strap is inside. But it works. I generally put the free end outside.

Learn from others mistakes, you will never live long enough to make them all.

[Hausse 0]

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Why are we using those weird buckles to fasten them???

Because they work, they're easy to use and inspect, they contain one moving part and have a high degree of reliability.

Any type of clip or locking buckle will have at least two moving parts, twice as many as the current arrangement.

On top of that, you would still need a threaded portion for the jumpers who prefer to loosen their chest strap after opening. So now you still have the same old problems in addition to the new problems.

Furthermore, any type of spring used to close or secure a clip or buckle would be a failure point you couldn't inspect. The spring will break when the spring wants to break, what then?

Proper training (a must for safe skydiving) along with complete and frequent gear checks (also a must for safe skydiving) will solve the problem, and possibly many others at the same time.

I vote for training and gear checks.

Great points, thanks this is the input I was looking for!

I definitely see the point about more moving parts etc.

[KellyF 16]

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]I like bringing up the routing because it is amazing how many people see that picture and immediately think it is not safe. The hardware is reversible so it is safe, just not conventional.

Structurally safe, yes, but near impossible for someone sitting across from that person to visually check the routing, which is what prompted the thread

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[peek 20]

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If everyone routed their chest strap "backwards", we might have a few more people getting out of airplanes without a properly fastened chest strap.

Fortunately we probably don't need to worry about that, because it is actually a lot of trouble to do it that way, and it is marginally less comfortable too.

One interesting thing that this routing can be used for is an instructor testing their student to see if they notice the difference without actually using a routing that is unsafe.

[dgw 8]

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The chest strap flat type adaptor commonly used ...!

The document is attached in case you do not have it.
Except it is now PS70101 since PIA took over the specs.

Notice that the specs say "reversible". This means you can thread your chest strap equivalent to the 1 inch wide chest strap in the picture.

(This always extends the thread quite a few posts!)

Well, it appears you have introduced a permanent modification to my rig

I have a Teardrop Superfly container, with a narrow chest strap. It comes without a dog leg on the end of the chest strap. I had one put on.

I tried the technique shown in your photos, and it worked, just like I thought it would. However, for the life of me, I cannot unthread it.

Not too sure about the 'reversibleness' of the practicalities. I've never had a problem unthreading it on the 'right' side. Interesting post.

[BlindBrick 0]

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I've never had a rig with anything BUT B-12's...other than my 'Stylemaster' which had QE's.

IMO they are safer than thread through hardware in that you pretty much gotta be brain dead to 'mis-use' the snap.

I've once had to drive the dz doctor out to the landing area to treat a jumper who had a freeflyer accidently open up her legstrap b12 during a sitfly.

-Blind

"If you end up in an alligator's jaws, naked, you probably did something to deserve it."

[Brains 2]

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Ok at the possibility of getting flamed here, How the hell do you mis-route a chest strap? They aren't exactly rocket science to figure out. I'm simply curious as to how this happens.

Every time you make something idiot proof, they make a better idiot!

Never look down on someone, unless they are going down on you.