Thanks Jim, knew I could count on you :^)
On November 4, 2015 3:58:03 PM PST, Jim - TFJ <jim@xxxxxxxxxxxxxxx> wrote:
That's why closed cell foam is better than open cell foam....
:-)
Jim G.
From: roc-chat-bounce@xxxxxxxxxxxxx
[mailto:roc-chat-bounce@xxxxxxxxxxxxx] On Behalf Of Cliff Sojourner
Sent: Wednesday, November 04, 2015 3:48 PM
To: roc-chat@xxxxxxxxxxxxx
Subject: [roc-chat] Re: Super Strypi
David, I was conflating two perennial debates in attempt at humor. oh
well.
(I tried foam in the fin can once; doesn't add strength, makes repairs
difficult, is hygroscopic, fail. but if you like it...)
On 2015-11-04 15:23, David Smith wrote:
Linear Polyurethane foam on the shock cord?
I use PML adjustable foam for fin cans and nose cones...
David P Smith
Tripoli 15803
NAR 78668
Amateur Extra: W6DPS
ROC Board Member
On Nov 4, 2015 3:19 PM, "Cliff Sojourner" <cls@xxxxxxxxxxxxx> wrote:
On 2015-11-04 14:01, David Smith wrote:
I always like to have my launch lugs free to spin.
And prefer tubular nylon shock cords...
hey David, what kind of LPU foam do you use on the shock cords?!?
Cliff
David P Smith
Tripoli 15803
NAR 78668
Amateur Extra: W6DPS
ROC Board Member
On Nov 4, 2015 1:59 PM, <kramer@xxxxxxxxxxxx> wrote:
The first launch of the SuperStrypi rocket
http://spaceflightnow.com/2015/11/04/air-force-declares-failure-on-super-strypi-test-launch/
failed early in the first stage burn. Not to speculate, but the rocket
did use a rail to launch. I'm thinking that they let the launch lugs
spin instead of having the fixed, this caused a gyroscopic progression
combined with the Corilolis effect caused flow separation at the lugs
resulting in unbalanced mach cone development resulting in asymmetrical
buffeting on the fins causing flight instability resulting in
failure....
If they ONLY would have kept the launch lugs from spinning the failure
could have been prevented...
Mike (nylon or Kevlar) Kramer
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