- This topic has 17 replies, 8 voices, and was last updated 15 years, 7 months ago by
Steve Jensen.
Steve Jensen.-
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edward
I could see that, however on my first L3 attempt my main went off while the rocket was still going about 300 mph and the nosecone came off and the parachute came out, making a mess of things.
Edward
Jeffrey Joe Hinton
All I could surmise was that as the chute and fire blanket were nearing the end of the tube, the air flow caused the chute and protector to start to bloom and consequently clog the exit. I’m not sure if the chute was wrapped once or twice around with shroud lines to prevent premature opening. I’m suggesting the possibility that the recovery package needs to be completely deployed prior to opening. Great boosts – rail straight unfortunate deployments. Even a parawad recovery means the system got out of the launch vehicle.
mule
I didn’t think he was wrapping the shroud lines around it. I can’t remember for sure so forgive me if I’m misremembering. We talked about it a little on the way out to it after the last launch. Very frustrating…
I thought it was still moving when it deployed, but how fast I wonder????John A. Wilke
The shrouds were *tightly* wrapped around the chute — at least for the 2nd boost.
This is one of the reasons I’m such a huge fan of pistons. They WILL get the laundry out. Your chute may still tangle, etc. but at least you have more of a fighting chance.
Disclaimer – I’d never use pistons in paper airframes… if the airframe gets dinged (possibly by rebound of a drogue section or any of a zillion other ways) then the piston can jam. In glass, carbon, and usually in phenolic, I really like ’em….
Steve Jensen
The second shot the chute was wrapped tightly by folding it in half, rolling it down, and tightly wrapping the lines around it. (I had help)
The shear pins were cleanly cut — 2-56 sized from Missileworks. They seemed to work well.
With 3.5 grams of BP, the altimeter “burped” at deployment (had a spike). So I feel the charge was sufficient, maybe big.
I think the ejection charge is leaking around the edges of the wrapped chute wad in the rather long tube and/or the nomex creates too much friction.
It’s a Sky Angle chute, which I’ve really stuffed into some other piston deployment rockets with absolute success.
I almost think I need a drogue just behind the nosecone and a deployment bag on this rocket.
Still, I had fun.
John A. Wilke
I almost think I need a drogue just behind the nosecone and a deployment bag on this rocket.
Actually, you need a piston just behnind the main chute 😀
Seriously, there have been a zillion similar flights that did not have a drogue behind the nosecone. Shouldn’t be necessary. In fact, it might even complicate things – if the drogue blooms quickly on exit, it may not allow the cone to pull the main out. If the descent profile didn’t allow for enough “oomph” to pull on your main – for example, if you tumbled just right – you may end up coming down under drogue.
I cannot figure out how that chute hung up twice…
edward
Pistons defintely are the way to go, I’ve switched and won’t go back. I still use a chute protector to help me pack the chute into the piston and make it nice and neat.
Edward
Steve Jensen
Edward, I’ve heard of this now from two people.
Pictures would be cool.
edward
Jeffrey Joe Hinton
mule
John A. Wilke
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