Yesterday I did have an unexpected crash with my Soarus Kyosho, 2m wingspan. First time with 2.74b.
Flight was short, nice takeoff, go to 80m altitude, start coordinated turn left, reduce speed and altitude and... not more any control, plane was nose down and crash into field with good speed.
It entered 10cm in ground, I did need some effort to extract it... The impact with ground was so big that battery case was broken.
I did use separate battery power for servos, (no jumper pn APM2.5), 4 x AA Sanyo Eneloop.
I did fly many hours with this h/w configuration, but with another (older) version of Arduplane.
I did fly this plane many times before, not major issues until yesterday. Wondering what could be the issue. I am confident is not my piloting skils, I have lot of hours piloting.
Could be brownout? I did check HVcc and looks good for me.
But all values from log and tlog stops at some moment. Even altitude, speed, throttle values is stoped abruptly.
The APM power supply was a separate source. Voltage/Current sensors was 180amp AttoPilot, but even connected, was not functional.
I will need to repair this plane, need lot of time and resources, but I need to know the reason of this crash and if this APM is still good.
On benchmark, after crash, all looks OK with APM, as gyro, compass, baro, all test in CLI looks good.
APM2.5, Ardupilot 2.74b., 433 telemetry, uBloxGPS