SDR ASAA2016081317685

Service difficulty report · A/C Pack · Boeing 737990

Difficulty date: August 13, 2016
Submitted: August 15, 2016
Operation: Air carrier
Aircraft: N305AS
Make and model: Boeing 737990
Aircraft serial: 30013
Aircraft time: 54,356 hours, 20,987 cycles
System (JASC): 2150 · Cabin Cooling System
Part: A/C Pack
Condition: Failed
Location: Left
Stage of operation: CR
How discovered: O
Nature of condition: J
Precautionary procedure: A

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

What was found

FL 240 CABIN ALTITUDE LIGHT ILLUMINATED. ACFT GROUNDED. CREW WAS UNABLE TO MAINTAIN ALTITUDE. CABIN PRESSURE WARN HORN SOUNDED. PERFORMED QRH AND DESCENDED DUE TO PACK. PERFORMED CONFIDENCE CHECK OF BOTH PACKS AFTER REVERSAL OF PACK, LEFT PACK FAILED CONFIDENCE. PERFORMED & WRENCHED CHECK VALVE FOR LEFT PACK. NO LEAKS AND DEFECTS NOTED. PERFORMED SINGLE PACK OPS CONFIDENCE CHECK FOR LEFT & RIGHT PACK, BOTH PACKS PERFORMED WITHIN AMM PARAMETERS, IAW AMM 21-00-05-700-801.