SDR ASAA2021050134725

Service difficulty report · Fmc · Boeing 737990ER

Difficulty date: May 1, 2021
Submitted: May 3, 2021
Operation: Air carrier
Aircraft: N459AS
Make and model: Boeing 737990ER
Aircraft serial: 36352
Aircraft time: 26,752 hours, 8,583 cycles
System (JASC): 3460 · Flight Management Computing Hardware System
Part: Fmc
Condition: Failed
Location: Right
Stage of operation: TX
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

BEFORE TAKEOFF, ON GROUND RIGHT FMC FAILED, RECOVERED AFTER APPROXIMATELY 1-2 MINITS. GROUNDED - YES. VERIFIED FAULT, CYCLED 2 C/B'S ACCOMP FMC BITE R/H FMC SHOWS INTERMITTENT FAULT, (WATCHDOG TIMER). VERIFIED FSEU HAS NO FAULTS. REF B737-900 FIM 27-51 TASK 801. ACCOMP FMC SENSOR STATUS ALL SHOW OK VERIFIED FMC FIXED OUTPUT SHOWS OK REF B737-900 AMM 34-61-00-710-026, FIM 34-61 TASK 801 & FIM 27-51 TASK 806.