SDR ASAA2023012391592

Service difficulty report · Fmc · Boeing 737990ER

Difficulty date: January 19, 2023
Submitted: January 23, 2023
Operation: Air carrier
Aircraft: N487AS
Make and model: Boeing 737990ER
Aircraft serial: 44108
Aircraft time: 26,849 hours, 8,281 cycles
System (JASC): 3460 · Flight Management Computing Hardware System
Part: Fmc
Condition: Faulted
Location: Unknown
Stage of operation: IN
How discovered: 9
Nature of condition: O
Precautionary procedure: K

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

What was found

APPROX 5 HRS INTO FLIGHT BOTH FMCS WENT BLANK AND FMC P/RST LIGHT ILLUMINATED. NO VTK OF MAP FLAGS WERE NOTICED ON EITHER NAV DISPLAYS. APPROX 1 MIN LATER. BOTH FMCS RETURNED TO NORMAL OPERATION. GROUNDED - YES. PERFORMED B737-900 FIM 34-61 TASK 807 A-E. CHECK OK. BOTH FMCS' OPERATIONAL. VERIFIED BOTH FMC SOFTWARE CONFIGURATION CHECK MATCHED WITHIN EACH OTHER REF B737-900 AMM 34-61-00-750-801. MATCHED.