Joe,

Actually, the 3 in 1 board does 4 things:

It has a gyro, a tail motor esc, a main motor esc, and a battery eliminator circuit, BEC.

With glo planes you used a separate battery pack to power the receiver and the servos.

With smaller electric heli's, the esc has a circuit to provide power to the receiver and servos
from the main battery pack, so no separate battery is needed for the receiver.

The bad news is the 3 in 1 board can fail on any of the 4 functions and the other 3 can still work.

Once I put too long a bolt in the tail motor mount. I managed to short circuit the tail motor wires.

The 3 in 1 smoked, but everything worked except the tail motor.

So, the fact that your servos still work doesn't mean you didn't fry the main motor esc.

If you saw smoke, it is likely the 3 in 1 was damaged as motors don't usually smoke.

If you look very carefully at the 3 in 1, you may be able to see "burn marks" where
something got too hot.

One trick is to cut the power immediately when you know you're going to fly into something.

You should take a close look at the main gear because if the rotors are stopped by a bush
or the ground, the main motor has enough power to grind the plastic teeth off the main gear.

If there is only slight damage, you may be able to salvage the gear by using a small common
screwdriver to plow out the grooves.

Check out ebay for cheap axe parts. I've found it's cheaper in the long run to just buy
a heli for parts. You should be able to get a complete flying heli for less than Tower's
price for a new 3 in 1 board.

Good luck.