FBodyexpert

Just finished building my Mini funtana, and I'm ready to fly. But I've never flown a plane with a fully simetrical airfoil. Can I adjust my alerons to give it a little flaps? Good Idea or bad idea? if so, how much?

FBodyexpert

also, weird thing.....I'm kinda new to electrics, especially brushless....I'm running an align heli motor, 400 size brushless outrunner 2800kv, an align 35amp brushless esc, and a 11.1v 12c 2200mah lipo. Direct drive to a 10x3.8 prop. The problem is that, even with a full charge, when i give it throttle and hold it there, Its got great pull. But after a few seconds it starts surging in almost like a tapping rythum. Then as I reduce throttle it regains power and a few seconds later does the same thing at that throttle position. If at anytime I cut the thottle completely the "cycle" restarts. I checked the temp on the motor and its running at about 139*F. Any ideas???

FBodyexpert

Someone please reply.....21 views and no one knows the answers?

jdetray

The surging is your ESC detecting that the battery voltage has dropped below the low voltage cutoff (LVC) point. You also mention that the motor is getting hot.

These two things tell you that you are drawing too much current.

With that high kV motor and that big prop, this is not surprising! You need to either prop down, get a lower kV motor, or put the motor in a gearbox. A motor with such a high kV is not intended to be used in direct drive, unless it's with a real small prop.

At 139°F, you may be close to permanently damaging the magnets in your motor. It depends on the magnet material. Once overheated to the point of damage, the magnets will never recover, and the motor will draw more current than ever, so it's a downhill spiral.

As for the battery, you'll eventually damage it with that setup. So both your motor and battery are at risk.

You need a wattmeter to know for sure what is happening, but it's safe to say that you're using much too large a prop for that motor.

- Jeff