# SDR WVBA2001050

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: September 27, 2001
- Submitted: September 28, 2001
- Operation: Air carrier
- Aircraft: [N59829](https://openairdocs.org/aircraft/N59829), registered now
- Make and model: Piper PA-31-350
- Registry model: [Piper PA-31-350](https://openairdocs.org/model/piper-pa-31-350) (OpenAirDocs)
- Aircraft serial: 317652081
- Engine: Lyc LTIO540*
- System (JASC): [2200 · Auto Flight System](https://openairdocs.org/jasc/2200)
- Part: Computer
- Part number: 011033T
- Part serial: 4848
- Condition: Failed
- Location: Pitch
- Part time: 2,246 hours
- Stage of operation: IN
- How discovered: V
- Nature of condition: O
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/WVBA2001050

## Discrepancy

THIS PITCH COMPUTER WAS A FACTORY REPAIR WHICH UPON RETURN FAILED IN THE SAME MANNER.  WHEN INSTALLED THE AIRCRAFT WOULD PITCH UP AND DOWN 5 DEGREES WHILE THE AUTOPILOT WAS ENGAGED FOR CRUISE.  THIS AUTOPILOT SYSTEM SEEMS TO BE PARTICULARLY SENSITIVE TO ANY AFT LOADS WITHIN THE ENVELOPE AND COULD BE A FACTOR IN THE PORPOISING PROBLEM.  THE UNIT WAS REMOVED AND REPLACED WITH A LOANER UNIT.

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