Saturday, November 5, 2016

Unstable Quinstar?

On TRF Les had an unstable Quinstar flight with a D12-0 engine.
Some thought maybe it got hung up on the launch rod, starting to spin on the way up. 

For anybody interested in a 24mm conversion, 
Here's my TRF response - 

I've launched my Quinstar with both C6 and D12 engines. My flights were stable.

I've attached a picture showing a D12 engine installed and how far it extends, 1/4" out the back.
Also shown is the 18mm adapter. The upper end slips inside the 20/50 centering ring used as an engine block.
With the 18mm adapter the casing extends 3/8" out.


To see the entire Quinstar build conversion from finish to the start: CLICK HERE

3 comments:

  1. I did much the same thing but let the extra tube hang out the front (scrapping the pentagonal piece). It flew well on a C6-0. I'll report back when I can fly it on a D12-0

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  2. Sorry for the late reply. I flew my Quinstar last Sunday on a D12-7. Why a 7, not a 0? Dummy me forgot to get D12-0s and I figured a 7 would fire close enough to the ground that the spin wouldn't be affected. Nope... The mass of the unburnt charge completely whacked the descent spin. The up part looked good tho!

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    Replies
    1. Hi Phil,
      Yeah, a seven second delay on a spinning saucer might be too long! I have launched my Quinstar with D12-3 engines and the ejection was right after apogee with a good spin down.

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