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  #1  
Old 08-31-2019, 09:27 AM
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Default Can the Spaceman be built to fly straight?

This is a Semroc xkit Spaceman, built per the original Estes plans. On an A8 it flies usually a spiral but veering off vertical till it ejects pretty far away. Then itís completely stable but seems to have some lift so itís veering toward the ground until impact. Is it possible to make it fly straight? I was thinking capping the big main tube at the top to stop the ring fin ahead of the CG might help, then a streamer taped to pthe engine could be put inside. Thoughts?
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Old 08-31-2019, 10:02 AM
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Iím building my first Spaceman currently, also a Semroc kit. But it is built stock, using the 13mm motors. Iíve not heard how well they fly normally, but would have to assume converting to 18mm is the issue. Did you use the four weights on the leg braces, or increase their size to counter the bigger motor?
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Old 08-31-2019, 10:11 AM
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The mini motor kit from erockets is a bit different from the xkit since it recovers the motor pod by streamer. The xkit is 18 mm ejecting motor. I would love to hear how the flight and recovery go.
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Old 08-31-2019, 10:44 AM
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The original Estes version used 18mm motors recommended all the way up to a C6-7, but 1/2A6-2 for first flight. It might be worth it to look at some original plans to see if anything is different. I don't think Estes would have recommended a C motor on something that wouldn't fly at least fairly straight.
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Old 08-31-2019, 10:58 AM
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Nope; it will only fly straight if you use a hi-thrust motor such as a B14 or D21/24.
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Old 08-31-2019, 03:07 PM
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Quote:
Originally Posted by tbzep
It might be worth it to look at some original plans to see if anything is different.


http://www.spacemodeling.org/jimz/estes/k-09.pdf

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Old 08-31-2019, 03:24 PM
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Semroc released a number of kits around 2008 as xkits - a bag of parts and no plans, the builder would go online and find the plans. Mine was an xkit, so it was built according to the plans above.
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Old 08-31-2019, 03:47 PM
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Quote:
Originally Posted by 5x7
Semroc released a number of kits around 2008 as xkits - a bag of parts and no plans, the builder would go online and find the plans. Mine was an xkit, so it was built according to the plans above.


Ahhh, didnít realize that was what you were talking about - an xkit is kind of like the BMS clone kits.
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Old 08-31-2019, 04:08 PM
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Quote:
Originally Posted by ghrocketman
Nope; it will only fly straight if you use a hi-thrust motor such as a B14 or D21/24.

Maybe some "accidental" contact between a B4-4 and a small drill bit would help the flight profile.
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Old 08-31-2019, 05:00 PM
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Quote:
Originally Posted by tbzep
Maybe some "accidental" contact between a B4-4 and a small drill bit would help the flight profile.


Like this ?
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