Quick attach seat

[councilman24 36]

Just for grins attached are two photos of Lee modeling a 1941 Switlik Safe-T-Chute Quick Attach Seat. DOM 1941 last packed and certified as airworthy in 1978. All cotton and I assume silk canopy. Still sealed.

BTW I'm old and can't for the life of me remember who on this forum gave this to me last year. My deepest apologies and please remind me who you are.

I'm old for my age.
Terry Urban
D-8631
FAA DPRE

[JerryBaumchen 1,068]

Hi Terry,

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Quick attach seat

Once it deploys, how are you suspended?

Jerry Baumchen

[councilman24 36]

JerryBaumchen

Hi Terry,

Quote

Quick attach seat

Once it deploys, how are you suspended?

Jerry Baumchen

Once you unwrap your arms like a chest mount. D rings below the chest strap. Show you when you get here.

I'm old for my age.
Terry Urban
D-8631
FAA DPRE

[JerryBaumchen 1,068]

Hi Terry,

Quote

Show you when you get here.

OK; I'll call you sometime Monday.

Quote

Once you unwrap your arms like a chest mount.

However, it is on the back side of the user, I still wonder how one would be suspended since it does look like the risers are sewn to the container.

The second photo is what got me to ask.

Jerry Baumchen

[RiggerLee 61]

I'm famous!

Basically from under your arm pits. I don'y think it wold hurt too bad. The rings are pretty far back. But it's weird. You'd be hanging with your arms in front of the risor junction at least on opening.

Lee

Lee
[email protected]
www.velocitysportswear.com

[riggerrob 561]

Another variant on Quick-Attachable seat-packs is illustrated on page 178 (section 5.024 Navy Seat Parachutes) of Poynter's Manual Volume 1. It illustrates a typical seat-type harness with long risers stowed down the back of the harness. The difference is that risers terminate with B4 snaps. Risers snap onto a pair of D-Rings protruding from the rear corners of the container.

To connect the harness and container, the pilot connects 4 snaps: 2 risers and 2 pack retainer belts. PRBs go straight up the main lift web (while seated) and snap onto chest-strap hardware. Presumably the ripcord is attached to the left PRB.

This alternate sounds more comfortable during opening, because risers just peel off the back-pad (like other seat-packs).

Though I have a couple of doubts.
First, I wonder if the average pilot could remember to snap all those 7 snaps (3 harness snaps plus 4 more attaching him to the container) when he boards the airplane.
Secondly, I wonder if those D-Rings would poke the pilot in his delicate backside?????

[riggerrob 561]

You guys tickled my curiosity, so I started sketching a modern QA seat type parachute. I reduced the number of snaps to 5 (3 harness & 2 risers) by including modern materials like Velcro and magnets.

Like the original military QA seat pack, my concept has separate harness and container. The pilot leaves the container in the cockpit most of the time. When the pilot wants to go flying, they don the harness and snug it up. Once they are seated, they grab 2 snaps (from the cockpit sides) and clip the snaps onto a pair of D-Rings on their chest.

My key innovation is routing harness risers over the shoulders and curving them forward under the armpits so that they hang near the chest strap. I started with an old seat pack, so that lower risers (while hanging under canopy) are 50" long. Both lower risers terminate with D-Rings (MBS 5,000 pounds). I am seriously considering using a torso harness to simplify donning and conceal lower risers. Both sets of risers will be concealed/protected by the usual riser covers. Velcro or magnets will close riser covers (as per modern containers). At a bare minimum, the harness will include side walls (between container and MLW) like a Security 150/250/350 or Australian Slimline PEP.
I am debating whether to sew an apron between risers to reduce the risk of a pilot tumbling between risers during opening.

Meanwhile, the container starts like a regular seat pack, except that risers are only 30" long and terminate in Snap hooks (MBS 5,000 pounds). Risers still exit the rear corners of the container (as per normal seat packs).
The new part is a fabric "skirt" that is sewn to 3 edges of the container/seat cushion (back and sides) and extends upwards to chest level. IOW fabric skirts resemble bucket seats.
Side skirts extend straight up from front corners to chest strap level. The upper front corners of the skirt terminate with snap hooks. The left side skirt also contains a ripcord handle pocket that hangs just below the chest strap (as per normal).
The back portion of the skirt guides the upper risers upwards. The key difference is that upper risers (when hanging under canopy) curve forward under the pilot's armpits. Upper risers clip to lower risers at chest level.
A secondary function of the back skirt is preventing the container from swinging so far forward that it blocks the pilots' legs as they bail out of a doomed airplane. A secondary function is that it reduces the risk of falling between the risers buttocks first. I am also contemplating sewing aprons between the risers to further reduce the risk of tumbling between risers.
The skirt will be made of Sumbrella or Dyvatain or a similar fabric that resists UV damage. UV resistant fabric will allow pilots to leave QA seat packs in the cockpit for extended periods of time without risking fading or loss of strength.

The only disadvantage is that extra-long risers limit QA seat packs to round canopies. Rounds can be installed without steering lines. Round canopies are not a big limitation since half the pilots who wear seat packs fly antique airplanes.

The primary reason I am sharing this (modern QA seat pack) concept on dz. com is to establish "prior art." I will cheerfully share sketches and prototypes with manufacturers. If any manufacturer wants to produce my concept: Sure! Just be polite enough to pay me royalties.