# SDR GTIA9700272

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: April 5, 1997
- Submitted: March 26, 2000
- Operation: Air carrier
- Aircraft: N969ML
- Make and model: Doug DC-9-31
- Registry model: [Doug DC-9-31](https://openairdocs.org/model/douglas-dc-9-31) (OpenAirDocs)
- Aircraft serial: 47268
- System (JASC): [2210 · Autopilot System](https://openairdocs.org/jasc/2210)
- Part: Autopilot
- Condition: Malfunctioned
- Location: E/E Compt
- Stage of operation: CR
- Nature of condition: O
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/GTIA9700272

## Discrepancy

DTW - FLT 428 - AUTOPILOT PORPOISES SEVERELY WHEN IN VERTICAL SPEED HOLD OR IN ATTITUDE HOLD.  PITCH HOLD WORKS OKAY.  DEFERRED PER MEL 22-1.  DMI NR 00372.  REFERENCE DMI NR 00372.  RAN COMPLETE CHECK OF AUTOPILOT SYSTEM, IT CHECKS GOOD IAW DC-9 MM 22-00-00.  THIS CLEARS DMI NR 00372.  (X)

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