SDR ASAA2019041729029

Service difficulty report · Fmc · Boeing 737990ER

Difficulty date: April 17, 2019
Submitted: April 18, 2019
Operation: Air carrier
Aircraft: N477AS
Make and model: Boeing 737990ER
Aircraft serial: 40716
Aircraft time: 15,437 hours, 4,978 cycles
System (JASC): 3460 · Flight Management Computing Hardware System
Part: Fmc
Part number: 0000
Condition: Malfunctioned
Location: Captain'S
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

AT CRUISE FLIGHT LEVEL 320, "VTK' FOLLOWED BY "MAP" DISPLAYED ON CAPTAIN'S NAV DISPLAY. LASTED ABOUT 15 SECONDS. NORMAL OPERATION FOLLOWED AFTER THAT. 1:30 LATER "VTK" ON CAPTAIN'S SIDE AND BOTH FMC'S LOST. FOLLOWED QRH, NO HELP. USING FMC ON RIGHT. "VTK" GONE, FMC 2 WORKED. GROUNDED - YES. REF B737-900 AMM 34-61-00-860-801, FIM 34-61 TASK 807, 34-61 TASK 837. OPS TEST NORMAL. COULD NOT DUPLICATE.