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Old 04-22-2021, 11:39 PM
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Ez2cDave Ez2cDave is offline
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Default MANUAL Calculation Of CENTER OF PRESSURE . . .

Back in the day, circa 1995, a Tripoli rocketeer, named Bruce Lee, developed a simplified method to manually calculate Center of Pressure.

His 10-year old son was able to do the computations with ease.

Dave F.
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Old 04-23-2021, 05:20 AM
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Smart 10-year old!
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  #3  
Old 04-23-2021, 07:30 AM
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I still use the cardboard cut-out method.
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Old 04-23-2021, 09:17 AM
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Quote:
Originally Posted by mojo1986
Smart 10-year old!


DEFINITELY, a LOT SMARTER than what today's "Schools" are turning out !

Dave F.
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Old 04-23-2021, 09:21 AM
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Quote:
Originally Posted by barone
I still use the cardboard cut-out method.


Nothing wrong with that, as it is very "conservative" about CP location.

It gives a "safe" CP location ( FORWARD of its ACTUAL location ) . . .

The "downside" to the Cardboard Cutout method is that it "calls for" extra Nose Weight, which reduces performance and creates an "overstable" situation.

Dave F.
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Last edited by Ez2cDave : 04-24-2021 at 04:31 PM.
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Old 04-23-2021, 09:43 AM
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Does this Bruce Lee also have a sister named Ugh ?

I don't ever bother with CP calculation. I just fly it. If it flies ok, the CP/CG relationship is ok too.
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Old 04-23-2021, 10:32 AM
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Quote:
Originally Posted by ghrocketman
I don't ever bother with CP calculation. I just fly it. If it flies ok, the CP/CG relationship is ok too.


That gave me a "flashback" to my youth . . . Home-made fireworks, labelled with a felt-tip marker "Light Fuse & Run Like Hell" . . . LOL !

Dave F.
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Old 04-23-2021, 10:57 AM
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Quote:
Originally Posted by ghrocketman
If it flies ok, the CP/CG relationship is ok too.

Their relationship may seem ok, but they still need a chaperone.
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Old 04-23-2021, 11:17 AM
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this is what OpenRocket is for. or RockSim or RASAero 2
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Old 04-23-2021, 11:39 AM
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Chaperone nuthin'
We dun't neeed no steeenkingg chaperone!
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