04-03-2008, 02:30 PM
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Launching since 1970.
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Join Date: Mar 2005
Location: Southern California
Posts: 2,188
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Quote:
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Originally Posted by poke44
For my tarc team i am a teacher for they used for 24mm rms f24w and f39t's
24 was to low and the 39 overshot wich seemed odd as both had the same impulse. We probably wont get in an official flight as they are kinda apathetic but the 24 shot us to aorund 650 and the 39 was around 850.
with times of 40 and 54 sec.
We also built a 29mm rms hobby and put in a f52t for our first rms launch and boy it was loud... but it went way up, 1200 or so... We had a fin can that we could exchange to a the same payload bay.
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Your F39 soounds like it will get you EXTREMELY close to the desired altitude and duration with the addition of ballast. You must be able to vary something for flights in suboptimal conditions (like wind), so add ballast for perfect results in no wind and remove the ballast for perfect flights in wind.
I saw a team get a darned good boost with a F42-4 Econojet in wind that was between 15 and 20 mph. They wanted to use an F20-7 but I vetoed that on safety grounds and I explained why in detail. |