I acquired this device from Para-Gear in 1984. I picked up another descender (without the webbing kit) from Check Six Aviation in 2000.
This is a unique kit designed to help parachutists extricate themselves from trees. It consists of descender and webbing packed into an olive-drab case measuring 35 cm by 35 cm by about 3 cm. The outside of the case is marked as follows:
The case is sewn on one side and secured with snaps on the remaining three sides. A snap on each corner presumably allows one to attach the device to one's remaining equipment.
The case contains about 140 feet (45 m) of 3/4-in (19 mm) tubular webbing folded 140 times. The folded bundle is secured by two elastic straps sewn to the case in multiple places, forming eight elastic loops per side. The webbing ends are stuffed into these loops. The webbing is white except for the final 25 feet (8 m) or so. (These lengths are approximate because I've only unfolded enough webbing to test the device. Putting the webbing back neatly is tedious.) The lower end of the webbing is doubled back on itself and sewn so that the descender cannot pass the end. The upper end of the webbing is sewn to a 35 mm. by 6.5 mm. cadmium-plated steel ring. This ring has a 2 feet (60 cm) of additional webbing sewn to it. The second piece terminates in a snap hook that can be clipped to the ring. The auxiliary webbing is marked "M. STEINTHAL & CO. INC. DATE MFD .JUNE 1967" on one side and "TCTO 14D1-2-628 C/W" on the other. The snap hook is stamped "66C1705" and "Fc 72"
The descender frame is a small cadmium-plated steel stamping with two rectangular holes at one end and a bend forming a hook at the other. The upper rectangular hole contains a captured brake bar. The brake bar is oval, measuring about 9.5 mm. high and 13 mm thick. Slots in each allow it to end ride on the frame. Thin (1/8-in) guide rods are fixed to the back of the device at the top and bottom of the wide portion of the frame. A spring-loaded catch is riveted to the bottom of the frame. This catch closes the hook. The back of the descender is stamped 66D1704.
The standing line webbing comes down through the upper guide, and through the lower hole in the frame. From there it passes back through the bottom of the upper hole, around the brake bar, and back through the lower hole, then out through the bottom guide.
I expected this device to be a disaster because the webbing pulls the brake bar tight against the frame, but when I tested it I found that the friction was nearly perfect for my tastes. Naturally, this device was intended for one-time emergency use, not daily sport rappelling. The idea of rappelling on webbing bothers me because tubular webbing lacks the abrasion resistance that good ropes have. I've heard that some canyoners prefer to use webbing instead of 9 mm. rope because of the weight savings. Perhaps their rock is more rounded and more abrasion resistant than what I am used to, if not, I question the safety of this practice.
Hale Laughlin offered to share his experience with this device:
Hi,
I ran across your site while doing some research for climbing; interesting site with interesting info about some unique equipment. I thought I would offer some information concerning the 'Air Force Descender' that you show. I have used the device for training purposes many times over the past 19 years and you are right on most of your specs. It does work well but there are some precautions that one must be aware of when employing this unique piece of military gear.
It was originally designed for use during Vietnam conflict where it was somewhat common for aircrew to get hung-up in tall jungle canopy after bailout. The braking device is very efficient, and requires very little effort to stop the descent. It operates opposite of most descenders in that you move the brake hand up and to the front of the face to stop the descent, lowering the brake hand to the 6 o'clock position allows the tape to feed through. Rate of descent should be 2-3 feet per second, not to exceed 10 feet per second.
Here is the main precaution; the brake heats up incredibly FAST. Experimenting with it several times, under contolled conditions of course, I have smelled, heard and seen the tape sizzling after stopping subsequent to a rapid 15-20 feet descent. I have no doubt that a sudden brake after a 25-30 foot rapid descent, would likely burn the tape in two, so slow and steady is the only method with this device.
The other precaution is that the tape must feed into the brake smoothly so that it doesn't get twisted and entangled in the brake device. Once this occurs, one must try to do a one armed pull-up, while maintaining a 'brake ready' position, in order to undo the jam. Again, slow and steady is the method that works best to prevent this. The device suits its designed intent well; lightweight, one-time use tool for aircrew to descend from a parachute hung-up in the trees. Thanks for the info on your site, hope this info is useful.
Cheers,G. Hale Laughlin
Note
to Hale's warning about overheating this device.
As for this device, I can see the military applications. As a pilot, I wonder why anyone would jump out of a perfectly good airplane for sport - being Pilot-In-Command is too much fun.
MiscDesc453.html/070318
©2007, Gary D. Storrick