SDR ASAA2014011612420

Service difficulty report · Precooler · Boeing 737990ER

Difficulty date: January 16, 2014
Submitted: January 21, 2014
Operation: Air carrier
Aircraft: N423AS
Make and model: Boeing 737990ER
Aircraft serial: 35206
Aircraft time: 2,813 hours, 914 cycles
System (JASC): 3610 · Pneumatic Distribution System
Part: Precooler
Condition: Failed
Location: Nr 1
Stage of operation: NR
How discovered: O
Nature of condition: O
Precautionary procedure: O

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

What was found

AT FL430, DUCT PRESSURE AS FOLLOWS L=26, R=42. ACFT GROUNDED. WHILE ACCOMPLISHING TASK CARD NG-36WC-00001, BLEED AIR SYS HEALTH CHECK, FOUND THAT THE NR 1 PRECOOLER VALVE AND NR 1 HIGH STAGE REGULATOR FAILED BLEED AIR SYS HEALTH CHECK. R & R THE NR 1 PRECOOLER CONTROL VALVE AND HIGH STAGE REGULATOR , REF AMM 36-12-02/401 AND 36-11-07/401. OPS CHECKS NORMAL. NO LEAKS NOTED. OPS CHECK GOOD IN REF TO AMM 36-11-710/801.