SDR ASAA2018070525303

Service difficulty report · Fmc · Boeing 737990ER

Difficulty date: July 5, 2018
Submitted: July 9, 2018
Operation: Air carrier
Aircraft: N402AS
Make and model: Boeing 737990ER
Aircraft serial: 41189
Aircraft time: 22,471 hours, 7,402 cycles
System (JASC): 3460 · Flight Management Computing Hardware System
Part: Fmc
Condition: Malfunctioned
Location: Cockpit
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

DURING CRUISE FLIGHT AT FL340 LT FMC FAILED FOR APPROXIMATELY 1 MINUTE WITH VTK DISPLAYED ON CAPTAIN INBOARD DU AND LNAV DISENGAGED, SELECTED B AUTOPILOT AND LNAV AND SYSTEM RESTORED. GROUNDED - YES. LEFT FMC LOGGED PRES POS LAT- RATE FAULT. ACCOMPLISHED BOTH FMC BITE TEST PROCEDURES PER FIM TASK 34-61-00-810-801 AND BOTH FMC OPS CK NORMAL, BOTH ADIRU`S BITE TEST NORMAL, NO CURRENT FAULT AND NO HISTORY 30 DAYS.