I’m using missionplanner as GCS and I am currently in the process of tuning my aircraft. A lot of tuning is done by taking “measurements’” by performing pulls and reading the log and adjusting accordingly. But is it possible to change and write parameters mid flight? Or is that too risky to attempt?
Specifically I want to do some TECS and NAV tuning.
Arduplane V 4.3.3
yes for sure
Depends on parameter 
Rolf
Aahh I see haha, not that straight forward.
I understand you probably can’t tell me yes or no for every parameter but does it suffice to say to use common sense?. For instance if I want to tune LIM_PITCH_MAX, i would set throttle to max, and perform a maximum pitch up. I would have a helper monitoring the airspeed in Mission planner. Then I would set the plane in loiter, edit the parameter according to the observed airspeed during the climb and try again.
Shouldn’t be a problem right?
I don’t know exactly, but I believe I can change nav speed and nav alt while in the air.
and as far I know you can assign RC switch to change tuning parameters
but you have to test first, cause I’m not sure and I don’t know ardupilot code structures
Sure, you can do it on the fly. You just have to be aware of what you’re tweaking and what could happen if you make a typing error, since you’re entering the data manually.
If you have little experience with AP, I would advise against it and rather change the desired parameters after the flight on the basis of log file evaluations
Rolf