Higher end UAVs are normally equipped with IFF transponders that
will transmit an emergency signal for location recovery. The flight
control system may even have FDR modules.
Some UAVs have autonomous pre-programmes that will direct the
UAVs to fly to certain locations if LOC is lost. Others will enable
parachutes to deploy, where necessary for safer landings.
Smaller tactical UAVs may not be equipped with such
functions (cost issues).