Max safe deployment velocity?

What are peoples thoughts regarding the max safe deployment velocity for a typical mid power (F <---> I impulse) rocket of paper or
phenolic and also glass construction, assuming tubular nylon harness, without causing damage such as a zipper? Perth Advanced Rocket Club - Western Australia http://waro.iinet.net.au/parc /
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lol! Well, it's the details I'm after...someone posted the question on our forum and I'm at a loss as to what to say, other than 'as slow as possible'.

I guess that is sort of valid, but not quite what I'm after ;-)

Sort of...Chuck Rudy thinks it looks pretty neat - I'm not sure how big it is - over 50 acres of pasture and hardly any trees. Great place to fly but our 3500ft waiver is very limiting :-(
Perth Advanced Rocket Club - Western Australia http://waro.iinet.net.au/parc /
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"Impakt" wrote

I'm fairly new to rocketry having only recently achieved level 1 on a scratch built, but anyone can have a view and here's mine:
The question is slightly spurios since we don't have a way a triggering ejection at a specific speed and its better to deploy the recovery device at high speed than not at all.
Effective design comes from designing recovery gear that is likely to survive high speed deployment - Info Central suggest recovery gear should be rated at 50 times the weight of the rocket.
Once the rocket has separated it will quickly slow because its areodynamics are wrecked so allow plenty of shock cord to give time for slowing down before the full recovery shock hits it. Elastic shock cord can cause the rocket parts to spring back an collide so builders seem to shun it but manufacturors still put it in their kits...
A thought I came across lately but I cant remember where, is that the parts should be designed so that they are unstable once separated. This way even if recovery devices prove not to be strong enough the rocket parts come in slowly and not ballistic.
Finally I recommend you test everything, especially my advice :-)
Halam
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