What was found
LOUD HISS HEARD SEAT 30A FLOOR LEVEL WHEN THROTTLES ARE RETARDED DURING DESCENT. RUBBER SMELL COMING FROM ROW 30 FLOOR VENTS. *S/D* THERE IS NO AMIS HISTORY FROM 12/1/00 TO 10/24/00 OF A RUBBER SMELL COMING FROM ROW 30 FLOOR VENTS. HOWEVER, THE LOUD HISS HEARD AT SEAT 30A FLOOR LEVEL WAS FOUND TO BE A CRACKED AFT CARGO HEAT DUCT WHICH WAS WELD REPAIRED (REFERENCE AMIS SEQUENCE 8492007 AND EVA SFO-2088). THE AIR LEAK IN THE DUCT MIGHT HAVE WARMED SURROUNDING INSULATION OR WALL PANELS AND CREATED THE NOTED SMELL. NO OTHER AMIS HISTORY REVEALS ADDITIONAL FINDINGS.