SDR UALA2010110804143

Service difficulty report · Duct · Boeing 757222

Difficulty date: November 7, 2010
Submitted: November 17, 2010
Operation: Air carrier
Aircraft: N549UA
Make and model: Boeing 757222
Aircraft serial: 25397
Aircraft time: 71,717 hours, 20,704 cycles
Engine: Pwa PW2037
System (JASC): 2120 · Air Distribution System
Part: Duct
Condition: Obstructed
Location: Cabin Air
Stage of operation: NR
How discovered: O
Nature of condition: E
Precautionary procedure: O

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

What was found

COCKPIT EXCEEDING LOUD EVEN W-RT RECIRCULATION FAN OFF. COMMUNICATION DIFFICULT. PERFORMED SVC TIP PER MM. FOUND FLOW RATE TO BE 458 CFM AND VELOCITY TO BE 5250 FPM. PER SVC TIP THIS INDICATES A BLOCKAGE. ALSO WALKED THRU CABIN WITH PACKS OPERATING AND FOUND AFT OF ROW 16 FLOW RATE AND NOISE DECREASED. ALL ACP WITH RT RECIRC FAN ON. 3 SHIFT SLOT REQUESTED TO CLEAN DUCTS AT SMB. CLEANED DUCTS. 1DB DIFFERENCE WITH RH RECIRCULATION FAN ON. WITHIN LIMITS PER MM.