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I've heard the opinion that using a short (6') bridle for low, go-and-throw jumps is an effective way to achieve more consistent opening altitudes.

The idea being that the jumper's body weight will start pulling the pc faster and leave less time for it to deflate after it reaches bridle stretch.

I am wondering how many jumpers out there actually use a shortened bridle for their go-and-throws and whether or not anyone has noticed a difference, whether it be in opening height or just consistency.

I don't understand. Can you elaborate on what you mean?

You're saying that the jumpers body weight loads the PC faster, and therefore reduces the chance for hesitations?

The jumpers weight is at the end of the lines, and doesn't really play on the PC inflation. The jumpers body weight can only be transferred (through the loaded lines) to the PC _after_ the canopy reaches line stretch, and even then only for a very tiny amount of time before the canopy expansion (when the jumpers body weight is supported by the canopy).

I do think that there is an argument for using a short bridle for very low go-and-throw handheld jumps, but it has nothing to do with the jumpers weight loading the PC, which I honestly can't see having very much influence on the overall deployment.

I can elaborate. Body weight was the wrong term. What I meant was the pc would be loaded by the extracting canopy sooner, reducing the chance for hesitation because it would have less time to float at the end of the bridle before being pulled to inflation.

I can see this making a difference if the goal was to pre-inflate the pc just prior to exit.

If you can reliably place the PC with an arms length bridle, it shouldn't have any chance to deflate prior to extraction.

The trick there is the "reliably place" bit, which is going to take a fair amount of practice, since you're talking about using this technique at very low altitudes.

If that's the goal, then the ideal bridle should be custom to the jumper, at exactly the right length to go from the pin to the jumpers hand. It would take a fair amount of experimentation in a rigging loft to get it perfect, but it should just be a matter of putting the rig on and off while adjusting the bridle length.

I think what you may be referring to, and what Tom briefly touches on, is the concept of inflating your PC before leaving the object and using that pre exit inflation to initiate a higher deployment. I believe I once heard of this as the "Feteris Method" if not him then some other old dude, there was some old school videos of guys waving massive PCs around and then jumping off of shit. Either way you definitely need a shorter bridle to make this type of deployment work.
If you are just talking about standard free falls with a 6ft bridle then I have no clue. But remember we ended up at 9ft for a reason. Why go backwards now? The shorter bridle will have less dynamic force when it hit's bridle stretch.
What is it you are jumping that several ft either way is a problem? If you aren't freefalling sub 200ft I wouldn't even waste my time with it.

Fledgling

This reminded me of bfl#50 Trevor with a 6 foot bridle

 'Trevor was jumping a Fury 220, with a sail slider packed into a deployment bag.

His older style Racer container had a pull out 30-inch F-111 pilot chute and a short 4-foot bridle.'

Seems that a few more things contributed.

Yeah like I said

Reminds me of someone who is changing around the gear

I know people that use shortened/modified bridles for static lining, but I never really saw the point for free fall. Lots of techniques exist to pre-inflate the pilot chute, or throwing it up on exit that work well for low freefall. keeping a pilot chute farther away from a burble always seemed like a good idea to me too. I guess if I'm thinking about freefalling something so low that 3-4 feet of bridle could make the difference between life and death, I'm probably just going to static line it. My short answer is, might work, but probably not worth the complication.

Having a bridle too short in a handheld PC situ can put your PC in your burble. There is a drag profile created by one´s body that determines the drag of the PC because the PC is inside this disrupted air flow. There is a critical area of the body drag profile that has a negative (towards the body) flow of air, just above this point is where the PC drag starts to take effect and starts increasing to Maximum drag for that PC diameter/type vs airspeed.
I hope this helps.
Take care,
space

I've used a 6'ish bridle for the last 170 jumps. From 190 freefall to 2 secs stowed IMHO it does 2 things well. Shorten opening height. Better heading performance. YMMV

How big is the burble on a go and throw deployment?

Small then bigger. Better know how to correctly throw pc for the jump you are on.

Two of my jumping buddies use this method and both have over or around 700 base jumps with most being in the slider off environment. I'm not a fan personally but i have witnessed it in person on quite a few jumps and it does indeed open significantly higher than myself. 20-30 ft higher to be exact

My gear:
Skunk Ape container, Basic Research Fox 285 and running a standard bridle with a toxic 42. If you want to be lame and argue pin tension, my pin tension is pretty low
Buddies gear:
Skunk Ape container, UL OSP 220 (240) running a 6 foot bridle with a bad seed 42. His pin tension is decently tight.

We are both running and throwing our pilot chutes up on exit and his is already popping pins before he is 10' below exit. He also uses the same bridle for static lining and the same bridle and pilot chute for sub 200' FF. He also does the pre inflate method and has the same results.

One can argue and state the obvious, that I have heavier gear. But I have seen video and picture evidence from Huck who jumps the same set up (6ft bridle) and a heavy flick 285 and is getting the same results. I can only speculate that the short delay FF wake is significantly less that what we have all feared to believe. That being said I'm sticking to my standard bridle and techniques haha.

...and if you place the PC incorrectly even after lots of practice, you'll end up with a massive hesitation. Running helps but I couldn't reliably pre-inflate with a poised exit so I gave it up.

If you're freefalling low enough exits that you need the difference between a normal or short bridle for your opening, then there's other things you should dial in (i.e. literally everything else about your technique and your gear) before going that route.

Right on. This is essentially what I have heard the results are when using the shorter bridle: that there is a significant gain in opening altitude, much more than just the 3' of extra bridle.

I believe this is due to the pc being loaded faster and the canopy having less time to generate downward momentum before being deployed.

Thanks everyone for the discussion.

For what it's worth, I have witnessed numerous freefall deployments using 6' bridles without any burble troubles.