Freebag - how does it work?

[addicted 0]

I've never been explained exactly how the freebag works. They've told me that the main purpose is to prevent an entanglement, but can anyone explain how it is ment to work? Pictures?

At my home dz all student rigs have round reserves.. maybe that's why i don't know much about the freebag system

[sid 1]

The deployment bag for the reserve is attached to a long (and wider) bridle and then to the springloaded pilot chute. When you deploy the reserve the pilot chute, bridle and deployment bag fly free of the reserve canopy thus eliminating any possibilty of it entangling with the deploying canopy. On your main the deployment bag is attached to the top surface of the canopy and you trail it and the pilot chute behind you during flight, on the reserve it flies free and you have nothing trailing behind you. This also improves the flight characteristics of the reserve (you're not dragging an inflated, spring loaded pilot chute behind you in flight).

Pete Draper,

Just because my life plan is written on the back of a Hooter's Napkin, it's still a life plan.... right?

[riggerrob 558]

addicted,
please update your post to tell us your home dropzone.

To expand upon Sid's explanation, an early selling point on freebags was that the wide bridle (3 inches on reserve vs. 1 inch on main) would provide enough drag to lift the bag off your back if you experienced a horseshoe type, high speed malfunction (i.e. pilot chute entangled with your foot).
Horseshoe malfunctions are rare. However, container designs have gotten much tighter over the years and no-one still believes that old marketing ploy.
Even at terminal velocity, a wide bridle produces about 8 pounds of drag while a decent pilot chute provides more than 80 pounds of drag.
At best a wide bridle will stabilize the freebag as it comes off your back during a horseshoe malfunction.

[damion75 0]

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addicted,
please update your post to tell us your home dropzone.

To expand upon Sid's explanation, an early selling point on freebags was that the wide bridle (3 inches on reserve vs. 1 inch on main) would provide enough drag to lift the bag off your back if you experienced a horseshoe type, high speed malfunction (i.e. pilot chute entangled with your foot).
Horseshoe malfunctions are rare. However, container designs have gotten much tighter over the years and no-one still believes that old marketing ploy.
Even at terminal velocity, a wide bridle produces about 8 pounds of drag while a decent pilot chute provides more than 80 pounds of drag.
At best a wide bridle will stabilize the freebag as it comes off your back during a horseshoe malfunction.

Follow on question from that then, when I just started I got shown over a stripped out rig by a rigger (I forget the type, but odds on it was one of the centres Javelins), and he showed me that there were a bunch of little pockets on the reserve bridle to provide additional drag - surely that would help enough unless:

a. They did this but have stopped
b. I am having a brain fart and remembering something which never happened...!

I shall have to watch closely at my next reserve repack!

***************

Not one shred of evidence supports the theory that life is serious - look at the platypus.

[billbooth 10]

In my tests, a horse shoed freebag bridle pulls only about one pound at the freebag end. Pockets on the bridle don't pull much more, and certainly not enough to pull a freebag out of a modern container. This is good, because the last thing you want during a pilot chute hesitation (common on internal spring-loaded pilot chute systems) is for your bridle to pull your bag out of the container and above the hesitating pilot chute. Reserve totals are rarely fun.

[damion75 0]

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In my tests, a horse shoed freebag bridle pulls only about one pound at the freebag end. Pockets on the bridle don't pull much more, and certainly not enough to pull a freebag out of a modern container. This is good, because the last thing you want during a pilot chute hesitation (common on internal spring-loaded pilot chute systems) is for your bridle to pull your bag out of the container and above the hesitating pilot chute. Reserve totals are rarely fun.

Thanks Bill! I don't think anyone could ask for a much more definitive source of info than that!

Its also good to know that my memory wasn't playing tricks on me...

***************

Not one shred of evidence supports the theory that life is serious - look at the platypus.

[diablopilot 2]

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(I forget the type, but odds on it was one of the centres Javelins), and he showed me that there were a bunch of little pockets on the reserve bridle to provide additional drag - surely that would help enough unless:

Yeah they look nice huh?

Probably won't do diddly, but they don't hurt anything.

Oh and you probably saw a Talon (RI) bridle. If it was on a Javelin I'd be surprised.

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You're not as good as you think you are. Seriously.

[riggerrob 558]

I have only seen assistor pockets sewn to reserve bridles made by Rigging Innovations (Talon 2, Telesis 2, Genera and Voodoo) and Northern Lite Enterprises/Velocity (Infinity).

[damion75 0]

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I have only seen assistor pockets sewn to reserve bridles made by Rigging Innovations (Talon 2, Telesis 2, Genera and Voodoo) and Northern Lite Enterprises/Velocity (Infinity).

Probably a Telesis then - UK Forces DZs tend to use Javelins and Telesis (latter for students with Skymasters and Mantas) My Bad!

***************

Not one shred of evidence supports the theory that life is serious - look at the platypus.

[riddler 0]

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bridle and deployment bag fly free of the reserve canopy thus eliminating any possibilty of it entangling with the deploying canopy.

I've always wondered about this. Has this ever happened? Was there an older design of a reserve bag that was attached to the canopy and got entangled with the reserve or departing main? Or was the freebag designed because someone just thought it could happen?

I guess if the reserve bag was attached to the canopy, there would be some chance of it entangling with a streamering main. But it seems unlikely, and I'm curious if that's ever happened.

AFAIK, the skyhook design keeps the freebag attached in some fashion, and I doubt Booth would have done that if he felt it was dangerous.

Edit for spelling and syntax.

Trapped on the surface of a sphere. XKCD

[ryoder 1,381]

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AFAIK, the skyhook design keeps the freebag attached in some fashion, and I doubt Booth would have done that if he felt it was dangerous.

No, it is still a FREE-bag. I've packed two of them.

"There are only three things of value: younger women, faster airplanes, and bigger crocodiles" - Arthur Jones.