SDR ASAA2019100293870

Service difficulty report · Fmc · Boeing 737990ER

Difficulty date: September 30, 2019
Submitted: October 2, 2019
Operation: Air carrier
Aircraft: N440AS
Make and model: Boeing 737990ER
Aircraft serial: 41705
Aircraft time: 23,514 hours, 7,645 cycles
System (JASC): 3460 · Flight Management Computing Hardware System
Part: Fmc
Condition: Malfunctioned
Location: Captain'S
Stage of operation: AP
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

APPROACHING SFO AT CREAN INTERSECTION, VTK FLAG WAS DISPLAYED ON CAPTAIN SIDE, FOLLOWED BY CAPT MAP FLAG. BOTH CDUS WENT BLANK AS EXPECTED. AFTER 3 MINUTES, VTK FLAG AND CAPT MAP FLAG WERE NO LONGER DISPLAYED AND THE WHOLE SYSTEM RESTORED ITSELF WITHIN 5 MINUTES. GROUNDED - YES. PERFORMED B737-900 FIM 34-61 TASK 836. FIM TASK CONFIRMED FAULT WAS INTERMITTENT. NO FURTHER DEFECTS AT THIS TIME.