My Kadet flew today!!!!


I honestly didn't think it would fly. The motor, according to Tower, is rated for planes up to 6.6 pounds. My bird tips the scales at 8.

But I did have a problem. And I need help to solve it.

First the specifications.

AXI 2826/12 motor
JETI 40Amp ESC (no BEC)
5S2P Thunder Power 4200mAh Batteries. (1 3S20, 1 2S2P wired in series)
11x6 Master Airscrew Electric Prop
Finished weight about 8 lb.

The symptoms.

On take-off when revved up to full throttle, there was a screaching sound.

The plane almost jumped off the ground. There was a bit of a wind, but others at the airfield said it took off good.

After about 2 minutes, the motor cut out. Stopped. The flight was a few full throttle loops, etc.

We thought something was very wrong. We landed. (I didn't fly it, a very good, very experienced pilot flew it.)

After some talking and deliberating. I swapped batteries to another set. I was thinking maybe my batteries weren't fully charged. But I had charged them before leaving the house. Or at least I had them on the charger. I'm still figuring out all the technology.

The same guy flew it again, and again, at about 2 minutes, engine cut out.

Next we decided on a test. First we wired up the 3S battery by itself. We put the plane in a ground test stand. We ran the motor alternating from about 50-60% throttle. With occasional 15 second bursts to full throttle. Ten minutes went by, no troubles.

Next we decided to try flying it on 4S setup. I removed a 3S battery pack and installed a 2S, and hooked the two 2S packs together into a 4S pack. We did not change anything else. We decided to fly it, we wanted to see how it would fly/behave. The take-off run was noticeably longer, but it did eventually lift off. We flew the bird for 10 minutes, non-stop, at about 50-60% throttle. And landed with battery power to spare.


So... Now I need to figure out what happened. I'm thinking there wasn't enough pitch in the 11" prop, the motor at full power spun too fast, the ESC shut the motor off.

So... What do I do. I want to get the take-off run back to the shorter length. I want to eliminate the engine cut-out. I want to return to the 5S2P setup if possible.

Suggestions?

I have a watt meter. So I can do some testing...


Help?


TIA


Lyndon