"That's the problem. It won't arm in flight mode. The red light blinks fast and the motors twitch. I can arm and disarm while in calibration mode, but not in normal mode."
Doing Esc calibration (transmitter on, throttle up, plug in battery, listen for beeps, unplug battery, plug back in, listen for more beeps, throttle down) motors spin, throttle works fine. When I get out of calibration mode (unplug battery, plug…