What was found
RDM - FLAMES REPORTED FROM APU EXHAUST DURING APU SHUTDOWN ON GROUND. NO ACTION REQUIRED BY FLIGHT OR GROUND CREW TO EXTINGUISH FIRE. FLAMES IMMEDIATELY SUBSIDED FOLLOWING SHUTDOWN. MAINTENANCE INSPECTED APU AND TAILCONE. MINOR PAINT DAMAGE TO TAILCONE NOTED. NO DAMAGE TO APU OR APU EXHAUST REPORTED. PERFORMED OPERATIONAL CHECK OF APU ON GROUND, AND WAS UNABLE TO DUPLICATE DISCREPANCY. PROBABLE CAUSE OF FLAMES WERE EXCESSIVE SURFACE WINDS BLOWING IN APU TAILPIPE. (W)