Hi. I have made some modifications to the MatrixPilot code to do tests on In flight tunable gain. If this is further refined, it will be possible to do tuning of P/D gains on roll, pitch and yaw axis while in flight. The idea is that the gains can be tuned with a spare button on your RC transmitter one after the other (separately) while you fly the plane in stabilized mode. The gain you want to tune is gradually increased until oscillation is seen at max desired airspeed and then reduced back somewhat to ensure stability on that axis with that gain. My code mods is a hack at the moment, but this is just to illustrate the concept.