Em 5/5/2012 10:17, John Ferrell escreveu:
> I do have a 10 pound pattern plane but the batteries are expensive and I=
=20
> rarely fly it. I prefer the 3 cell Lipo's. The public perception is that=
=20
> electrics are safer. I disagree, A careless flyer will at some point=20
> allow an unplanned motor start. Danger to people and property.  An IC=20
> usually stops with a prop strike. A electric chews on what ever it=20
> encounters until power is removed.


Not brushless motors with a good modern controller. Indeed, for a
brushless motor run, the controller has to do a damn lot of work.
If anything wrong happens, the motor simply stops, possibly blowing some
MOSFETS in the controller.
The good controllers will detect if the motor got stuck and stop it,
only restarting after the throttle is set to zero and up again.


>   I have had a speed controller catch=20
> fire.  I did manage to not burn the airplane up!
>
> The Lipo's we use are bare cells. charge & discharge are up to the user.=
=20
> Too fast of either makes for a road flare. Best done outside!


Early Lipos were much more dangerous than modern ones.

>
> Foamies are neat! Small fields are fine. Break it into pieces, glue it=20
> back together and fly some more.
> No more nasty oil to deal with though!

I agree!


Isaac

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