What was found
(CAN) AT FL 350, ONE HOUR INTO FLIGHT, DOOR SEAL BLEW. CABIN ALTITUDE CLIMBED RAPIDLY TO 18,000 FEET. REPLACED CABIN DOOR SEAL DUE TO SUSPECTED MOISTURE AND FREEZING, THEREFORE, BLOCKING THE SUPPLY OF AIR TO KEEP THE DOOR SEAL INFLATED. ENTIRE SEAL INFLATION PLUMBING PURGED OF MOISTURE. PART TC: 2,691. AIRCRAFT TT: 2,848.