I’ve had some time to take the Wing Thing Two apart to do some testing, which turned out to be very interesting.
Firstly, I ran the HET Typhoon Micro 6/3D motor on the bench with the Graupner 8×4.5 folding prop, just as the final flights in the air had been. Any throttle setting above about 60% resulted in running problems with the motor. It looked as though the voltage and RPM was too high, causing the speed controller to skip. Measuring the power and RPM at this setting I obtained the following data:
135 watts, 13.3 amps, 6000 RPM
That’s with a Tsunami 10A controller with a 3S 1300mAH LiPo, so I’m exceeding the 10A controller limit and 90W stated maximum power output. The Kv for the motor is 1500 and idle RPM 10,800, so the 6,000 RPM measured is 56%, which is much lower than I would like.
Next, I extracted the motor from the fuselage and this is what I discovered:
It appears that the first crash pushed the rotating part of the motor backwards (left=front of aircraft in picture), leaving the magnets only partially exposed. This must completely change the motor characteristics, which is why it was behaving rather oddly on the bench test. I’ve never seen a motor do this before, so it was a new one on me. Anyway, the 3S LiPo and 8×4.5 prop should be in the right area for this type of aircraft, so I’m going to fix the motor, reassemble everything and test again.
Just to round things off, I also weighed all the components so I have some data to put into the simulator:
Fuselage, Motor, ESC, Receiver (FrSky DR4-II), Prop: 139g
Hyperion 1300 mAH 3S LiPo: 108g
2xOuter Wing Panels, Centre Wing Section, 2xFins, Wing Joiners, 2x Elevon Servos: 210g
So, the total flying weight was 457g.