SDR ASAA2014072208645

Service difficulty report · Fmc · Boeing 737990ER

Difficulty date: July 22, 2014
Submitted: July 24, 2014
Operation: Air carrier
Aircraft: N408AS
Make and model: Boeing 737990ER
Aircraft serial: 41732
Aircraft time: 6,449 hours, 2,041 cycles
System (JASC): 3460 · Flight Management Computing Hardware System
Part: Fmc
Condition: Malfunctioned
Stage of operation: DE
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

TEMPORARY DUAL FMC FAILURE DURING DESCENT. VTK AND MAP FAILURE FLAGS ON BOTH DISPLAYS, BOTH FMC'S FAILED. NORMAL OPS RETURNED AFTER ABOUT ONE MINUTE. NOTE: FAILURE DID NOT OCCUR IN ETOPS AIRSPACE. ACFT GROUNDED. PERFORMED FIM 34-61 TASK 801. FMC SENSOR STATUS SHOWS NO LT & RT FAULTS. INFLT SHOWS FAULTS ON FMC LT & RT FLT LEG 1 PERFORMED FIM 34-61, TASK 807. BOTH FMC'S GROUND VERIFICATION NORMAL.