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Old 05-26-2019, 12:34 PM
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Rktman Rktman is offline
Mad for modrocs
 
Join Date: May 2019
Location: Chapel Hill, NC
Posts: 71
Default A case of overstability?

Not sure which forum this belongs in, but this one looks like the most appropriate and the one most likely full of very knowledgeable builders. I'm trying to diagnose the problem with this oddroc design which just won't launch straight. It leaves the rod okay but after 10 or 15 feet it starts to go off-vertical and/or corkscrewing in big loops, and only kind of straightens out close to apogee. The CG is certainly far enough forward to be stable and I even added lead weights to the nose cone but nothing changed.

Is it possible it's overstable and every slight gust of wind will make it veer off at a tangent? It's currently sitting near the top of a 50' tree but I'd like to build a replacement that'll work like it should and won't pose a hazard to myself or any unnoticed spectators.
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