# SDR ASAA2020100933326

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: October 9, 2020
- Submitted: October 12, 2020
- Operation: Air carrier
- Aircraft: [N457AS](https://openairdocs.org/aircraft/N457AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 36355
- Aircraft time: 24,832 hours, 8,017 cycles
- System (JASC): [2210 · Autopilot System](https://openairdocs.org/jasc/2210)
- Part: Autopilot Sys
- Condition: Malfunctioned
- Stage of operation: LD
- How discovered: O
- Nature of condition: O
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2020100933326

## Discrepancy

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.

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