H Motor World Record Build

flyguy614

Matt Dahle Photography
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This is fantastic. One question. What do you mean by trapezoidal fins? Your shape actually looks fairly optimal in that it pushes the CP back with as little area as possible.

Cheers, Alex

Yeah, this fin shape ended up giving me similar performance, and it should be stronger for the fins (especially with a through-the-wall into the tailcone)
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Adrian A

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Nicely done!

Looking at the video, I wouldn't blame the tower. It came out of it vertically with no tilt angular rates that I could see. It looks like the tilting only started when it was about 2 tower lengths above the ground. To me it looks like a small misalignment between the thrust of the motor and the CG. A trick I used on my altitude attempts was to roll the rocket on a level table and adjust the CG axially until it rolled uniformly. But if the rocket thrust is misaligned coming out of the motor at first because of specifics of the grain geometry, the only way you're going to beat that is with bigger fins and a longer tower.
 
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