SDR ASAA2022122741261

Service difficulty report · Fmc · Boeing 737890

Difficulty date: December 27, 2022
Submitted: December 28, 2022
Operation: Air carrier
Aircraft: N594AS
Make and model: Boeing 737890
Aircraft serial: 35191
Aircraft time: 52,378 hours, 15,509 cycles
System (JASC): 3460 · Flight Management Computing Hardware System
Part: Fmc
Condition: Faulted
Stage of operation: CR
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

WENT INTO "SINGLE FMC OPERATION" IN SCRATCH PAD FOR ABOUT A MINUTE, AT CRUISE. IT KNOCKED US OUT OF VNAV/LNAV. ER REENGAGED MODES AND OPERATED NORMALLY. GROUNDED - YES. FMC-L RECORDED "PRES POS LAT-RATE" ON PREVIOUS FLT LEG, NO FAULTS NOTED ON ADIRS-L BITE, FMS OPS NORMAL REF B737-800 FIM 34-61 TASK 824.