nomex parachute

At the risk of sounding silly, has anyone ever tried making a parachute out of nomex instead of protecting it with that?

Hmmm, makes sense if you can find a lightweight nomex material. That reminds me of the Seinfeld question: if the black box is the only thing to survive a plane crash, why don't they just make the plane out of the black box? Lol

watermelonman said:

At the risk of sounding silly, has anyone ever tried making a parachute out of nomex instead of protecting it with that?

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These are kevlar and nomex.

https://www.the-rocketman.com/kevlar.html

watermelonman said:

At the risk of sounding silly, has anyone ever tried making a parachute out of nomex instead of protecting it with that?

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I'll sell one or two if you let me know the size.

Seems like a derp moment

Exactimator said:

These are kevlar and nomex.

https://www.the-rocketman.com/kevlar.html

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Man wish I had that kind of money!! $50 for a twelve inch chute :shock:

Kevlar and Nomex are, as you can see, more expensive than nylon. I would imagine there is a difference in porosity between those materials, as well, which should affect the drag. But, it is a good idea.

watermelonman said:

At the risk of sounding silly, has anyone ever tried making a parachute out of nomex instead of protecting it with that?

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Pratt Hobbies made them with kevlar shroud lines, just saw one last weekend. There are large size X-chutes made for ballistic deployment that are Kevlar.
I think Areo-Con & RocketMan [previously mentioned] had them.

I made a Kevlar chute for the opposite reason, to work in cold
It was to be used in a high altitude project as a drogue. Kevlar freezes at a much lower temp than nylon.

M

JJSR said:

Man wish I had that kind of money!! $50 for a twelve inch chute :shock:

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But 7ft is only $110 which is cheaper than most nylon chutes.

Zebedee said:

But 7ft is only $110 which is cheaper than most nylon chutes.

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probably a typo left out a 1 in the price for a 7 footer :lol:

Nomex is a lot heavier than nylon. Would add a lot of weight on the pad....

I can't see any reason you why you couldn't sew a chute from lightweight fiberglass, Kevlar(R) or Nomex(R) fabric and fiberglass, Kevlar(R) or Nomex(R) lines or braid.

https://www.cstsales.com/e_glass_cloth.html is an example.

Bob

watermelonman said:

At the risk of sounding silly, has anyone ever tried making a parachute out of nomex instead of protecting it with that?

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(Note that I've read thru the other responses)...

A few observations:

* Kevlar / Nomex materials are generally not available in material weights that are anywhere near as lightweight as the classic ripstop (RS) nylon (that I am aware of). Thus, a canopy made of these materials is a compromise, at best.

* Kevlar / Nomex are considerably more expensive than RS nylon.

...so... I have to ask this question:

What part of the flight are these special characteristics (with their attendant drawbacks) necessary? (with the understanding that, if you use them, you are having to live with the drawbacks for the *entire* recovery portion of the flight).

IOW, flame retardancy is necessary for, at most, 2 or 3 seconds at the very beginning of the recovery phase. After that, these 'special characteristics' are entirely unnecessary.

???? Does that make sense? Not really.

Just like a multi-stage rocket that sheds the part of the rocket for an early phase of the flight when it is no longer needed (in a later portion of the flight), utilizing recovery materials *only where (and when) they are needed* and then discarding them seems to make equal sense.

Thus, making a deployment bag (or, even, just a simple outer bag) out of Kevlar / Nomex seems considerably more sensible.

I made an outer container (hardly more than a simple open 'soup can' shape) out of some teflon coated ironing board cover - with a bottom 'disk' of some ceramic cloth (covered with RTV silicone) that my (normal nylon pack cloth) deployment bag went it -- provided with an 18-24" piece of 1/8" bungee cord tied back to the shock cord anchorage -- such that, upon deployment, was easily stripped off (once it was free of the 'flame' environment of the ejection charge going off). Never once had even the slightest hint of scorch on the deployment bag.

(Note: Mark Clark's point about a high altitude canopy for sub-freezing temps makes sense and is considered a separate, special case -- with the additional point that all the canopies for the manned missions (and the Mars missions as well, I believe) are still just nylon - and this is a considerably extended portion of time in a far harsher environment). However, a Kevlar / Nomex pilot or drogue (in Clark's case) is still a sensible approach with little downside).

-- john.

Kevlar is certainly available in 1.0 and 1.7 oz./sqyd fabric https://www.cstsales.com/aramid_fabric.html but it is expensive. Nomex should be available in similar weights.

Fiber glass is available in 0.6, 0.7, 1.4 and 1.6 oz/sqyd from the same supplier https://www.cstsales.com/e_glass_cloth.html at reasonable prices and you used to able to purchase surplus flare parachutes made of fiberglass from several vendors. It's flameproof as well.

These are the same weights or lower than the standard rip-stop hobby rocket parachutes which tend to be overbuilt with 1.7 oz. per sqyd. Military Parachute Fabric Specifications can be downloaded from https://www.perftex.com/specificati...arycanopy-specification-outline/download.html

You can get flame resistant rip-stop nylon but it is heavier than the basic fabric because the flame resistance comes from a coating. https://www.onlinefabricstore.net/c...oup-nylon/use-general-purpose/type-fabric.htm shows a 1.9 oz/sqyd RS nylon when coated with the retardant coating weighing 2.3 oz/sqyd.

Bob

bobkrech said:

Kevlar is certainly available in 1.0 and 1.7 oz./sqyd fabric https://www.cstsales.com/aramid_fabric.html but it is expensive. Nomex should be available in similar weights.

Fiber glass is available in 0.6, 0.7, 1.4 and 1.6 oz/sqyd from the same supplier https://www.cstsales.com/e_glass_cloth.html at reasonable prices and you used to able to purchase surplus flare parachutes made of fiberglass from several vendors. It's flameproof as well.

These are the same weights or lower than the standard rip-stop hobby rocket parachutes which tend to be overbuilt with 1.7 oz. per sqyd. Military Parachute Fabric Specifications can be downloaded from https://www.perftex.com/specificati...arycanopy-specification-outline/download.html

You can get flame resistant rip-stop nylon but it is heavier than the basic fabric because the flame resistance comes from a coating. https://www.onlinefabricstore.net/c...oup-nylon/use-general-purpose/type-fabric.htm shows a 1.9 oz/sqyd RS nylon when coated with the retardant coating weighing 2.3 oz/sqyd.

Bob

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My experience with woven fabrics is that they're great for epoxying, but the weave isn't terribly tight. Fraying around the edges is almost guaranteed, and any asymmetric force tends to open up the weave in the center of the fabric. I think it would be really cool to see fiberglass or Kevlar in a much tighter weave (and smaller threads)--kind of like a textile fabric.

At my work we had a chute for the Huygens lander. It was Kevlar that looked like yellow silk. IIRC it was 15 feet diameter and packed 3" dia x 2 1/2" tall. We had to send it back to Marconi.
We made the ejection charge.

M

There used to be a light weight Kevlar specialty fabric available from Russia - if you could find a way to get it that is - that was much tighter weave and finer yarn than anything currently available. It was still an open weave compared to anything used in chutes though. I have perhaps 9M of that fabric on hand and it took me a year to track down the remaining supply in existence and to acquire it. It isn't going into chutes...

Kevlar and similar materials are interesting choices for high altitude high performance flights, where if something goes wrong, deployment may be at over M1. If you want it to work, these materials make sense. I watched a friend's rocket have drag separation at the burnout of an N. The Rocketman drogue caused the rocket to undergo very rapid deceleration! It also tore apart the Kevlar recovery harness and the drogue was never found. But it saved the rocket and the main survived to do its job.

Sometimes, when you need a really beefy drogue, you really need a beefy drogue! That's the other reason for at times using materials like Kevlar and other heavy weight fabrics for a drogue.

Gerald

MClark said:

At my work we had a chute for the Huygens lander. It was Kevlar that looked like yellow silk. IIRC it was 15 feet diameter and packed 3" dia x 2 1/2" tall. We had to send it back to Marconi.
We made the ejection charge.

M

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Wow that's some good packing. Probably cost about $25,000 or so though I suspect.

Welding sleeves. Very cheap. Treated cotton. I use it in place of kevlar sheet to burrito my chutes.