GPS Rescue

Now part of GPS RTH

GPS Rescue was inherited from Betaflight, where it was written for multirotors, and did not work correctly on a fixed-wing aircraft. It was first made to drive the same fixed-wing-native controller as GPS RTH instead (firmware#146), and the redundant GPS RESCUE switch that duplicated GPS RTH has since been removed entirely -- see the GPS RTH page for how the controller actually behaves, the settings, and its known limits.

The Failsafe tab's Stage 2 GPS Rescue procedure is unaffected and still exists -- selecting it on the Failsafe tab starts the same GPS RTH controller automatically if the radio link is lost and stays lost. See that page for the full staged behavior, and GPS RTH for how the controller itself works.

The old multirotor rescue code (a hover-throttle-learning descent algorithm, wrong for a wing) is still in the firmware but has not been reachable from anywhere for a while. The gps_rescue_* CLI settings still exist but have no effect.