Question for the Chute Riggers...

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Toobuilder

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First off, I'm not intending to put anyone on the spot for regulatory guidance here, just an opinion of what to expect:

My L39 has cold seats, but the seatback chutes are in place and form the primary restraint interface to the jet. When we ferried the jet to SoCal a few years ago the chutes were way out of date. We briefed that we'd only jump if the jet was on fire, and take our chances that the chutes would open as a "last chance" option.

As an Experimental, I have the option of abandoning the cold seats and chutes entirely, but I'm just wondering what I should expect WRT the existing chutes, packed for probably 20 years without seeing the light of day. Anyone have any actual experience with Soviet era chutes and what kind of condition they are likely to be in after decades sitting in a seatback? Should I even bother opening them up, or is there a chance they just need an inspection and repack?
 

Riggerrob

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After 20 years, they may have suffered fraying or rusting or UV damage. Only a rigger can confirm those sorts of damage when he is hands-on.

Those old Russian 'chutes are extremely rare and English-language manuals are even rarer. Ergo, hardly any North America riggers know how to repack them.

I have only worked on one old Russian 'chute. It was for a Yak-55 that had just arrived for an airshow and someone had accidentally pulled the ripcord. It was faded and frayed and some of the hardware (e.g. KAP-3 auto opener) was rusty. Pack-opening-bands had last their "spring" decades ago. It was also designed for high-speed, jet fighters making it far too complex for low-altitude use.
It took me three tries to reclose. I told the mechanic that my labor was free if he never asked for a signature or receipt. I also told him that if he brought it back to my loft, he would have to endure a lengthy lecture about why modern seat-packs made by Butler or Para-Phernalia or Strong were infinitely better for his low-altitude, low-airspeed airplane.

If you want modern seat packs - specifically built for your L-29 - contact Butler or Strong. Theirs include extra hardware so that the parachute harness also serves as seat-belts.
 

Aesquire

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My suggestion is find a rigger who's willing to work on them, and ask around for happy customers. Let him inspect & recommend repacking or retirement to ceiling decoration.

Rubber bands and bungees age & perish. The nylon can get sticky from improper storage, mold if damp, and/or almost "melted" to a lump in hot cars.

The local hang glider club used to have a yearly chute deployment party. We'd hang a control bar & hang strap from a tree or sturdy playground thing, get in harness, climb a ladder to hook in, then often have others spin/swing/jostle the "simulator" ( maybe with eyes closed, until the call for go) and you attempt a deployment, hand deploy to " clean air" ( and downwind ). Good practice. I've seen lumps of nylon fly to the end of the tether and thump on the ground. Definitely would have been an unpleasant surprise if deployed for a real need.

I pack my own chutes, but while Absolutely Not A Professional, I did learn how back in the Before Time, ( when I was skydiving... ) and when getting a new to me reserve/emergency parachute, took it to a Pro for inspection, repack, and a lesson on techniques and cautions.

The modern stuff is so much better. Opens smoother, quicker, more comfortable to wear.
 

Hephaestus

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Did you check with the vintage yak/mig guys?

I feel like I've seen mention of an old russian military rigger (was it the yak 55 owners talking about it?) - out somewhere towards toronto (canada not california); who was highly recommended.
 

Toobuilder

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Nope. I have not looked into this at all. I'm guessing that replacement options are readily available considering the popularity of the L-39, but my question was just to satisfy initial curiosity.
 

proppastie

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I have a Vietnam era back pack I was told was too old. ...two riggers said no way, ....the rap is the plasticizers in the nylon straps and stitching is gone and it could fail.,....
 

proppastie

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'"

Please clarify ... or type neater.
As I was told. ...the straps for the harness are old and stiff ...the chute straps too.....because as I was told they get too old. I do not know if that is correct but the an engineer/rigger at the local parachute manufacturing facility near me got irate when I implied doubt. ...
 

Aesquire

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I've jumped WW2 surplus chutes. Seriously, I rented one for my First competition, and the reserve was dated 1945. The main, a T-10, was approaching more patch than original. A few pounds, I bet. ( which I didn't know Until I packed it on the airfield, It was, Can I rent a chute? Sure, grab, toss ) Not only did it work, but I finished mid pack in accuracy.

Rubber bands, otoh, die fairly quickly, depending on storage, and bungees have a finite lifespan. Webbing isn't Immortal, but...

I can understand fearing the liability of your family suing in all directions in case you jump into a thunderstorm.
 

Riggerrob

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If nylon webbing has gotten stiff, it should retire to a museum.
You see, part of the advantage of nylon is that it has a bit of elasticity. During hard openings, it stretches - a little - to absorb opening shock. This reminds me of a conversation with parachute harness/container designer Jeff Johnson who was explaining some updates on Mirage harness. He said that Type 8 webbing proved stronger because it stretched a bit more than Type 7 webbing.
Type 7 webbing has a minimum breaking strength of 6,000 pounds while Type 8 has a 4,000 pound MBS. A single layer of Type 7 is enough for a main lift web or leg strap, but many manufacturers use doubled Type 8 instead.

Many skydiving manufacturers suggest a 15 or 20 year service life. After 20 years, pilot emergency parachutes wore by glider pilots are faded, frayed and filthy. Many European nations ground parachutes after 20 years. When I taught a rigging course in Switzerland, we practiced inspecting and packing 'chutes that were 21, 24 and 24 years old. They were all faded and all needed major repairs (e.g. replace hardware) if they were returning to service. They were grounded by Swiss law and most North American instructors would have asked "Are you sure this is still airworthy?"
Older 'chutes have been jumped, but they rested in a military warehouse for 10 or 13 years.
If your webbing has gone stiff, then it was not stored properly.
 
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Riggerrob

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Aesquire,
Trivia point, the US Army did not adopt the T-10 main parachute until after World War 2. Over the years T-10s got numerous up-grades (e.g. anti-inversion net). Now T-10s are being replaced because modern paratroopers are taller and more muscular and only sissies jump with rucksacks weighing less than 100 pounds.
Hah!
Hah!
 

Riggerrob

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yes Dear BJC,
A "nut under" can be very uncomfortable when you are hanging in the harness.
Hah!
Hah!
Ideally, leg straps lay on the crease between your buttocks and thighs. Many skydivers add bungee straps to hold leg straps in the correct position while they sit-fly or free-fly or just flail around the sky.
Hah!
Hah!
The long back-pads (40 inches = 1 meter) - on long-back containers - help hold leg straps in the correct position. Some aerobatic pilots request extra-long back-pads - regular length (20 to 24 inches) on their regular back type parachutes, just to prevent them from rising high enough to press on the back of their necks when they push inverted.
 

Riggerrob

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Never store a chute in a hot area or in sunshine. Don't even leave it in the airplane in the sunshine.


BJC
At a minimum, toss a leather jacket over your 'chute if you leave it parked in the sun at a fly-in. When you return to home base, hang your 'chute in a cool, dry, dark metal locker.
 

Aesquire

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Ditto on leg straps. You can hear badly adjusted straps from the ground. ;)

The T-10s I jumped had the "double L" modification, done by & for civilian use, but no anti inversion or skirt mesh, that came later. I think the oldest was a '56? 35 feet of OD green. The reserve I jumped at the West Point college invitational was a '45. I didn't need it, since I cleared a barber pole malfunction on my second jump.

Quite exciting. I credit my instructors, and the hang gliding experience. Fly through the problem.

If the webbing is stiff & kinda "crusty"? Replace. Totally agree.

Over the years I've acquired a rep as a safety nut. But practical experience sometimes conflicts with ideal.

I've long complained about motorcycle riders wearing the minimum legal half helmet. until I was first at a crash scene where one absolutely saved the riders life. I still advocate full coverage helmets, but anything is better than nothing.

I stand by my original post here. The New Stuff works better.
 

Riggerrob

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"
... Over the years I've acquired a rep as a safety nut. But practical experience sometimes conflicts with ideal. ...
"

Over the years, I have gained a reputation as a fascist control freak when it comes to suspension lines. The end result was my fleet of tandems going 1500 jumps between malfunctions when everyone else was doing well to go 750 jumps between malfunctions.
Oh! And that was with Spectra lines. The newer Vectra suspension line lasts much longer.
 

proppastie

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If nylon webbing has gotten stiff, it should retire to a museum.
The chute has been stored inside and dry in a closet since it was last packed in the 80's ....without even looking at it I was told it was too old and "no they would not repack it".......The harness is massive, .....military ......a new chute and lines if needed can not cost as much as a new rig I would think......so the gist of what I have read here is yes it could/could not...... be usable.
 

Traskel

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Wow.. Am I understanding correctly that you can afford to fly an L-39 and you are "wondering if you should chance using it's original parachutes?.." Sorry, but that's freakin' nuts. It was pointed out that Strong makes a replacement, please get one. And you other guys jumping T-10's and giggling about malfunctions? And you laugh at PM for his lack of safety antics? Pot - meet kettle.. ;)
 
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