Re: Elec. motor speed controller question

Ted W Lee wrote:
> I have a P-47 control line plan (from a 1947 MI mag.), and would like to
> use an elec. motor instead of gas. Would a speed controller be required
> here? Thanks, Ted.
> 
If you want to use a brushless motor you'll need a speed controller -- 
brushless motors need some electronics provide the commutation that 
brushes provide on a brushed motor.  Even with a brushed motor it's a 
good idea to have a speed controller that'll limit current in the event 
that the motor gets stalled -- a hard landing that stops the prop is 
much less severe than a hard landing that stops the prop, ruins the 
motor, and possibly makes the batteries burst into flame.

As the other responder noted, there are timers for control line use.  I 
don't know who carries them.  If you're in the US (or not) a check on 
Brodak's website, or a call, may get you an answer.

-- 

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

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