SDR ASAA2021011433889

Service difficulty report · Fmc · Boeing 737990ER

Difficulty date: January 14, 2021
Submitted: January 20, 2021
Operation: Air carrier
Aircraft: N459AS
Make and model: Boeing 737990ER
Aircraft serial: 36352
Aircraft time: 25,738 hours, 8,254 cycles
System (JASC): 3460 · Flight Management Computing Hardware System
Part: Fmc
Condition: Malfunctioned
Location: Right
Stage of operation: DE
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

AT FL290 RT SIDE NAV DISPLAY SHOWED "VTK". FMC SHOWED 1 SINGLE FMC OPERATION IN SCRATCH PAD. THE FAULT CORRECTED ITSELF WITH 10 SEC, BUT APPEARED AGAIN FOR 10 SECONDS AS WE DESCENDED THROUGH FL270. AGAIN CORRECTED ITSELF AND WORKED PROPERLY FOR REMAINDER OF FLIGHT. QRH REVIVED. GROUNDED-YES. ACCOMPLISHED BITE PROCEDURE ON RT FMC, NO CURRENT FAULT. INTERMETTENT FAULT DISAPPEARED, REF B737-900 AMM 34-61-801. A/C OK FOR SERVICE.