03-28-2010, 01:16 PM
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BARCLONE Rocketry
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Join Date: Mar 2005
Location: Mobile, Alabama
Posts: 5,357
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Quote:
Originally Posted by stantonjtroy
...18-25 fps decent rate under chute is normal so having these speeds at deployment is ok. 29fps is a little fast...
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At least for me, 18-25 FPS is on the high side of a safe Dv, given that most of our LPR stuff uses traditional plastic chutes with carpet thread shrouds. I don't like hearing my parachutes "explode open" with an audible pop when they're still 800-1000 feet up - this is a clear indicator the Dv is too high. What I and others here are saying is, why not design these rockets so that the Dv is as LOW as we can get them, instead of just "trying to keep it under the limit"? The lower you can get the Dv, the better the chance of a safe recovery. It puts a lower stress on the recovery system, and anytime you can do that, it's better.
That's what "rocket science" is about - making the rocket do what we want it to...
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