Service difficulty report · Fmc · Boeing 737990ER

Difficulty date
August 24, 2016
Submitted
August 26, 2016
Operation
Air carrier
Aircraft
N467AS
Make and model
Boeing 737990ER
Aircraft serial
36362
Aircraft time
8,951 hours, 2,918 cycles
Part
Fmc
Part number
1762000101
Part serial
012060
Condition
Failed
Location
E&E Bay
Part time
1,312 hours, 439 cycles
Stage of operation
NR
How discovered
O
Nature of condition
J
Precautionary procedure
K

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

What was found

WHEN PRESSING LINE SELECT KEY 6R TO REQUEST ENROUTE WINDS ON RT CDU TWICE, VTK FOLLOWED BY MAP DISPLAYED ON CAPTAIN'S NAV DISPLAY, ACCOMPANIED BY LOSS OFF FMC DATA ON BOTH CDUS, SEEMINGLY FMC FAILURE. RETURNED TO NORMAL FUNCTION BEFORE CHECKLIST QRH STARTED. EXACT SAME THING HAPPENED WHEN REQUESTING ENROUTE WINDS FROM CAPTAIN'S CDU. ALL RETURNED TO NORMAL BEFORE QRH RUN. 4TH TIME FAIL WITHOUT TOUCH ENGINE/CDU. ACFT GROUNDED. REPLACED NR 1 FMC, RESET C/B'S, LOADED DATABASE SOFTWARE OPTIONS BCG-01P-96, MEDB BCG01TA0, NAV DATA ASA1160901, PERFORMED DEFAULTS 557302-002, SYS TESTS GOOD, REF AMM TASK 34-61-00-710-801. PERFORMED LT FMC DRAG FACTOR ADJUSTMENT, REF AMM 34-61-00.