Service difficulty report · Structure · Doug DC931

Difficulty date
May 29, 2008
Submitted
July 24, 2008
Operation
Air carrier
Aircraft
N8920E
Make and model
Doug DC931
Aircraft serial
45835
Aircraft time
77,803 hours, 79,257 cycles
Part
Structure
Condition
Leaking
Location
Fuselage
Stage of operation
CR
How discovered
O
Nature of condition
J
Precautionary procedure
B

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

What was found

AT FL 310 RED "CABIN PRESS" WARNING LIGHT ILLUMINATED. BOTH ENGINE AND AIRFOIL ICE PROTECTION SYSTEMS OPERATING. COM PROCEDURES TO REGAIN CONTROL OF CABIN PRESSURE COMPLETED BUT CABIN STILL CONTINUED TO CLIMB AT AN INCREASING RATE. DECLARED AN EMERGENCY AND INITIATED AN EMERGENCY DESCENT TO 10,000 FT. CABIN PRESSURIZATION STARTED FOLLOWING PRESSURE CONTROLLER COMMANDS AT ABOUT 3.5 PSI DURING DESCENT. NO MENTION OF MASK DEPLOYMENT AND ACFT LANDED SAFELY AT STL. MX DID BITE CHECK BOTH PRESSURE CONTROLLERS AND NO EXISTING FAULTS SHOWED. TAIL COMPARTMENT INSPECTED FOR LOOSE OR BLOWN DUCTING WITH BOTH APU AND EACH PACK INDIVIDUALLY. NO LEAKS FOUND AND VESSEL PRESSURIZED NORMALLY ON GROUND. FURTHER MX FOUND THAT THE ACFT WOULD NOT PASS CABIN PRESSURE DECAY CHECK. DETERMINED NUMEROUS LEAKS IN THE CABIN AND LT PACK SYSTEM WERE CAUSE. ALL LEAKS FOUND WERE REPAIRED AND THE PRESSURE SYSTEM OPERATED NORMALLY. (A)

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