Re: P-40 (Pica????)

Harry Kolomyjec wrote:
"Six_O'Clock_High" <Six_O'Clock_High@xxxxxxxxxxxxxxxx> wrote in message news:ddydnd-Gqej4QZjUnZ2dnUVZ_sDinZ2d@xxxxxxxxxxxxxxxx
Being a sucker, I recently acquired a P-40 that the seller claimed it was a Pica, but I don't recall them doing that particular bird unless it was many years ago. I missed out on their P-51 but did get the Spitfire. This bird seems to be all wood with plastic in the cowl area and guns only.

The bird appears to be in reasonably good shape except for some glaring problems with rudder/elevator movement conflicts and other controllability issues. Some dummy hot glued the servos in and used easy connectors on all the surfaces. I am in recovery mode and will fly this bird as soon as I am satisfied that all the decencies are corrected safely.

That being said, I need some information.

Where should the CG be and what should the control throws be?

If you have this kit hiding in the attic, please post answers for me. I can (and if necessary will ) use the TLAR method, but actual real values tend to be better.


Jim Branaum
AMA 1428

Hi Jim,

If the wingspan of your P-40 is 71 1/4 inches, it's a1/6th scale Pica, the 1/5th is 86 inches.
I have the 1/6th kit and the following info is from that kit.
The root chord of the wing is 16 5/8, and the plans show the c/g at 3 3/32nd from the front.
The c/g shown is at the forward edge of the front spar's WEBBING, but you are allowed
a "safe" range of 3/8in either side of the c/g marking. Start at the c/g and adjust for your
flying habits.

Elevator - 1 to 1 1/2 in. each way.
Rudder - Full throw
Aileron - 3/4 to 1 in. each way.
Flaps - no more than 35 degrees.

Good luck,

And let us know how it goes, eh?


Tim Wescott
Wescott Design Services

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"Applied Control Theory for Embedded Systems" gives you just what it says.
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