# SDR ASAA2016080917654

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 9, 2016
- Submitted: August 11, 2016
- Operation: Air carrier
- Aircraft: [N570AS](https://openairdocs.org/aircraft/N570AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 35185
- Aircraft time: 36,235 hours, 10,749 cycles
- System (JASC): [2210 · Autopilot System](https://openairdocs.org/jasc/2210)
- Part: Autoland Sys
- Condition: Malfunctioned
- Stage of operation: AP
- 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/ASAA2016080917654

## Discrepancy

DURING PRACTICE HYBRID APPROACH, TRACKING & ALIGNMENT WAS GOOD UNTIL APPROXIMATELY 10-15 FEET AGL. AT THAT POINT THE ACFT BEGAN DRIFTING TO THE RIGHT OF CENTERLINE. AT TOUCHED DOWN, THE ACFT WAS WELL RIGHT OF THE RUNWAY CENTERLINE & CONTINUED DRIFTING RIGHT.  DISENGAGED AUTOPILOT,  STILL DRIFTING RIGHT, THE WHOLE FUSELAGE WAS RIGHT OF CENTERLINE. WINDS WERE APPROXIMATELY 190 DEGREES AT 3 KNOTS.  PROTECTED AREA WAS CLEAR. ACFT GROUNDED.  PERFORMED A FAULT REVIEW (BITE GROUP 20) AND A LAND VERIFY TEST (BITE GROUP 49)  IAW AMM 22-00-01/201. ALL TESTS NORMAL, NO FAULTS NOTED. PERFORMED A HGS SYSTEM TEST IAW SMM 34-36-00.  ALL TESTS NORMAL. PERFORMED A HGS FAULT REVIEW/ISOLATION TEST IAW SMM 34-36-00, FOUND FAULT 'ILS ANOMALY DETECT.' PERFORMED AN ILS/MMR DFCS LRU REPLACEMENT TEST (BITE GROUP 38), AND A HGS SENSOR TEST FOR MMR/ILS IAW SMM 34-36-00.  ALL TESTS NORMAL.  ACFT REMAINS CAT IIIA AUTOLAND & HGS QUALIFIED.

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