SDR SB05112

Service difficulty report · Outflow Valve · Boeing 737301

Difficulty date
September 9, 2005
Submitted
September 12, 2005
Operation
Air carrier
Aircraft
N352US
Make and model
Boeing 737301
Aircraft serial
23555
Part
Outflow Valve
Part number
7110033
Part serial
177958
Condition
Leaking
Location
Cabin Pressure
Part time
56,090 hours, 36,307 cycles
Stage of operation
CR
How discovered
O
Nature of condition
J
Precautionary procedure
O

As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.

What was found

AIRCRAFT WOULD NOT MAINTAIN CABIN PRESSURIZATION. AT FL030, CABIN ALTITUDE CLIMBED 1,200 FEET PER MINUTE WITH OUTFLOW VALVE FULLY CLOSED. CREW DESCENDED BELOW FL020 BEFORE CABIN ALTITUDE WOULD DESCEND BELOW 8,000 FEET. FLIGHT CONTINUED. MX PRESSURIZED AIRCRAFT. FOUND AFT OUTFLOW VALVE LEAKING EXCESSIVELY. REPLACED AFT OUTFLOW VALVE. OPS CHECK GOOD. ALSO FOUND AFT CARGO DOOR SEAL PULLED FROM RETAINER, AFT RIGHT SERVICE DOOR UPPER SEAL LEAKING AND RIGHT PACK BAY FLEX SEAL AT FORWARD BULKHEAD OF PACK BAY LEAKING. REINSTALLED AFT CARGO DOOR SEAL INTO RETAINER, CLEANED AFT RIGHT SERVICE DOOR SEAL AND REPLACED FLEX SEAL AT FORWARD BULKHEAD OF PACK BAY. PRESSURIZATION LEAK RATE WITHIN LIMITS.