Many local stores and places like walmart and target sell cheap countdown timers. I epoxied a clothspin to the back of one and can clip it to the TX antenna. Cheap, easy, and works well.

If you don't want to run the full throttle on the ground test (I've never bothered with that myself), you can get pretty close by going up a little at a time. Start with a full tank of fuel, fly 10min or whatever you've been normally doing during flight training, then land. Now empty the tank. Was there a lot of fuel left or just a little? If you use a hand-crank pump, you can count revolutions and figure out roughly how full the tank was. Or you can take the wing off before emptying the tank if you can see it from inside. Just about anything works to get an estimate of how much fuel is left.

If you flew 10min, and you think you had about half a tank, then fly for 13min or so and check again. Then do it again at 15min then 16min and so on. Don't make a big jump. And check your fuel level each time.

If you ever land with very little fuel left, reduce the time by a 1-2min and you're done.



The DX5 is fine for the most part. As an instructor, I find the location of the buddy cord to be rather brain-dead though. And the fact that a JR/Spektrum trainer cord often doesn't fit into the plastic around the trainer port with out some trimming of the rubber outter cover of the cord's plug or TX body is just silly as well. It's almost like no one at Spektrum ever actually tried to fly using 2 of those TXs on a buddy cord.

But other than the buddy cord follies, it's a solid, basic TX. No programming features of course.