SDR ASAA11510580

Service difficulty report · Regulator · Boeing 737890

Difficulty date: October 23, 2011
Submitted: October 31, 2011
Operation: Air carrier
Aircraft: N568AS
Make and model: Boeing 737890
Aircraft serial: 35183
Aircraft time: 18,111 hours, 5,811 cycles
System (JASC): 3610 · Pneumatic Distribution System
Part: Regulator
Part number: 1074926
Part serial: 10148
Condition: Failed
Location: Nr 1 Engine
Part time: 18,170 hours, 5,830 cycles
Stage of operation: CL
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

INITIAL CLIMBOUT RIGHT DUCT PRESSURE 44 LEFT DUCT PRESSURE 22 STAYED LIKE THAT UNTIL FL 300 RIGHT 40 LEFT 25. LEVEL FL 360 V 380 DUCT PRESSURE VARIED FROM 7-20 PSI DIFFERENCE. RIGHT HIGH. PERFORMED BLEED AIR HEALTH CHECK ON NR 1 ENG. REF AMM 36-11-00-700-801. FOUND BLEED AIR REGULATOR FAILED. REPLACED NR 1 BLEED AIR REGULATOR. REF AMM 36-11-03. OPS & LEAK CHECKED NORMAL. NO LEAKS NOTED. PERFORMED PRECOOLER HEALTH CHECK REF AMM 36-12-00-700-801. NO DEFECTS NOTED.