Closed quick link, coming undone during flight, captured on video

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JimJarvis50

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Amazing video. I would have thought this was impossible.
Not impossible at all. I've had it happen twice! The first time was a flight to around 50K. The fin can separated from the harness when the main came out. I never knew why it happened. The second time was on a flight to around 14K as I recall. When we got to the rocket, no fin can - where have I seen this before? We looked around and there was the fin can about 100 feet away, separated again when the main came out. The second flight was on video. It doesn't show the quicklink opening, but it shows the spinning quite well. Now, I use a swivel and tape the quicklinks (or just use an old quicklink that won't easily open). This isn't a one-in-a-million thing - it's much more likely to happen then that.

Jim

 

kramer714

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Coriolis effect problem. In the southern hemisphere it would spin the other way and tighten up. Just switch to a left handed threaded coupler for northern hemisphere flights.
 

Handeman

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I've had a lot of fin cans that spin like that. It's why I always put a ball bearing swivel between the fin can and shock cord on all DD rockets. I've never seen a payload section spin like that. Understandable that the main would get twisted up in those conditions.

I'm surprised the quick line opened when the main didn't. You see a lot of rocket come down ballistic with the payload leading the fin can and the fin can falls a long way and hits hard at the end of the cord. I would expect a quick link to fail in those conditions, but with the drogue keeping things pretty even and the main twisting and not opening, that seems kind of weird that the link would fail. If you fly these things long enough, nothing surprises you any longer.
 
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