in the morning figured out how to resolve problem that grey loudspeaker in top of remote control prevents from taking off: calibrate gyros and then it works
main problem of the last days: mounted the propeller wrong ( ); accidentially mounted all 4 wrong this time and we did not take off, but got pressed into the ground, so we noticed
after solving the problem, we were super motivated to take off right after lunch
start measurements at 12:48:30
made a roughly 150x150m^2 survey partly over the ROV non-walking area and partly further away from the ship
all went very well
stopped program, changed batteries, started measurement again and flew two vertical profiles: one over ROV area, one further out