SDR ASAA2021040434510

Service difficulty report · Fmc · Boeing 737890

Difficulty date: April 4, 2021
Submitted: April 6, 2021
Operation: Air carrier
Aircraft: N537AS
Make and model: Boeing 737890
Aircraft serial: 35204
Aircraft time: 34,607 hours, 10,057 cycles
System (JASC): 3460 · Flight Management Computing Hardware System
Part: Fmc
Condition: Malfunctioned
Location: Left
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

INITIATED VNAV CLIMB FROM FL 360 TO FL 380 JUST WHILE PASSING 30N54. UPON LEVELING @ FL 380 RIGHT FMC FAILED INTERMITTENTLY TWICE. THEN LEFT FMC FAILED. QRH APPLIED AS BOTH FMC'S RESOLVED ON OWN. AFTER RESOLUTION, FMC,GPS, AND IRS POSITIONS ALL NORMAL. ANP-.03. GROUNDED - YES. PERFORMED B737-800 FIM 34-61 TASK 836 CYCLED BOTH FMCS CIRCUIT BREAKERS. FMC RESTORED, NO DEFECTS NOTED