| > My plane flipped over and the prop hit the ground staying a few | > seconds locked with 1/2 throttle. When I finally releases the prop, | > noticed the speed control had burnt out! Shouldnt the speed contls | > come with any sort of protection to avoid? | | Yes, if you don'=t mind the extra half ounce, the extra $10 and the | extra 5% power loss....
You're exaggerating quite a bit here ...
It could be built into the ESC -- an extra chip that cuts the throttle off if the ESC gets too hot or too much current goes through it. There's a few ways they could do this that wouldn't increase the resistance (i.e. reduce power) at all. It would probably only require a single chip, so the added weight would be much less than one gram, let alone half an ounce.
I doubt it would add $10 to the cost to manufacture, but they might jack up the price by $10 for the extra feature.
The other option is to add a fuse. An automotive mini blade fuse weighs about one gram (I just measured it) and the resistance added is miniscule (I couldn't even measure it when I tried.) The cost was about 40 cents if I remember right.
Somebody else suggested just cutting power when your prop is about to hit the ground -- which is a good idea, electric or glow. But it's not the complete answer. First, you can just plain forget. And if your plane starts getting hit with interference and crashes, the motor may try and start up without you even moving the stick. Or if you forget to turn off your plane before the transmitter, it might start up as soon as you turn off the transmitter. And I had an ESC catch fire for some unknown reason right after hand launch -- obviously a fuse wouldn't have stopped whatever the problem was, but it might have saved the ESC well enough for me to figure out what the hell went wrong. Instead, I got to send a melted hunk of ESC to Astroflight and they replaced it for $60 or so. That, and it messed up my plane somewhat.
If you ask me, park fliers and ESCs should come from the factory with a fuse already installed inline with the motor or battery. Something large -- like for a 10 amp ESC, a 20 amp fuse, so there's no danger of it blowing during normal use.
If somebody wants to remove/bypass the fuse, they certainly can, but they should know the risks first.
| > It was a Great planes c-5 nano spc, hoocked to a 600mah, 7.2V batt.