Service difficulty report · Autopilot Sys · Boeing 737990ER

Difficulty date
October 9, 2020
Submitted
October 12, 2020
Operation
Air carrier
Aircraft
N457AS
Make and model
Boeing 737990ER
Aircraft serial
36355
Aircraft time
24,832 hours, 8,017 cycles
Part
Autopilot Sys
Condition
Malfunctioned
Stage of operation
LD
How discovered
O
Nature of condition
O
Precautionary procedure
O

As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.

What was found

FOLLOWED PROCEDURE FOR HYBRID/HGS APPROACH, NO ANOMALIES OBSERVED UNTIL APPROX 80' AGL. AIRCRAFT DRIFTED TO RIGHT OF CENTERLINE, THEN CORRECTED LEFT OF CENTERLINE. A/C WAS STILL DRIFTING WHEN AP DISCONNECTED MANUALLY. PERFORMED MANUAL LANDING WINDS 130/5. GROUNDED-YES. ACCOMPLISHED 737NG LLM LAND VERIFIED TEST, ALL TEST PASSED B737-900 AMM 22-11-00-700-801, AND HGS-400. SYSTEM OPS TEST PASSED SMM 34-36-00.