As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER APU START AND TAIL FLOOD LIGHTS TURNED ON , BOTH PILOT AND FUEL LINEMAN OBSERVED BLUE FLAME AND SMOKE COMING FROM RT TAIL FLOOD LIGHT. RAN APU SEVERAL TIMES, TURNED FLOOD LTS. ON/OFF DURING START AND NORMAL OPERATION. NO INDICATION OF HIGH APU ITT. NO EVIDANCE OF FLASHES OR FLAMES NOTED FROM RIGHT TAIL SIDE OR APU EXHAUST AREA. ALL WORK PERFORMED IAW MM 49-80-00 & 33-40-00 AND AFM.