OK, so I got the Flight Recorder working is sirf mode.
But when I tried to actually fly it, it was a bit weird.
At first, it kept losing GPS fix and switching itself into KILL and refused to do anything. After a few restarts, it seemed to stop doing that, and switching to the Takeoff block span the motors up, but not fast enough to actually take off - it just sat there with everything spinning.
Am I do something wrong? What am I actually supposed to do for takeoff? Go to Start Engine first? Or what?