SDR ASAA2018010223075

Service difficulty report · Warning Message · Boeing 737890

Difficulty date: January 2, 2018
Submitted: January 4, 2018
Operation: Air carrier
Aircraft: N514AS
Make and model: Boeing 737890
Aircraft serial: 35193
Aircraft time: 35,432 hours, 10,655 cycles
System (JASC): 2210 · Autopilot System
Part: Warning Message
Condition: Illuminated
Stage of operation: CR
How discovered: V
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

FL 340 NEG TURBULENCE. F/O FLIGHT DIRECTOR ON. AUTOPILOT B CMD DISENGAGED. RE-ENGAGED MULTIPLE TIMES. LASTED 1-15 MINUTES BEFORE IT WOULD DISENGAGE. TRIED BOTH AUTOPILOT A AND B IN CMD MODE. RE-ENGAGED AUTOPILOT B CMD AND IT REMAINED ENGAGED. GROUNDED - YES. REVIEWED FLIGHT FAULTS- FOUND MX MESSAGE 22-11208 ON BOTH A AND B AUTOPILOTS, CORRESPONDING TO FLIGHT DECK EFFECT. DID B737-800 FIM 22-13 TASK 818 WITH NO FAULTS. NO HISTORY 90 DAYS. ALSO DID LAND VERIFY REF DFCS BITE GP 49 WITH NO FAULTS.