# SDR DHL2001721008

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: September 25, 2001
- Submitted: September 26, 2001
- Operation: Air carrier
- Aircraft: N721DH
- Make and model: Boeing 727228
- Aircraft serial: 19545
- System (JASC): [2212 · Altitude Controller](https://openairdocs.org/jasc/2212)
- Part: Autopilot Sys
- Condition: Malfunctioned
- Location: Cockpit
- Stage of operation: CR
- How discovered: O
- Nature of condition: F
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/DHL2001721008

## Discrepancy

EACH TIME ALTITUDE HOLD IS DISENGAGED, A/C ABRUPTLY PITCHES UP AND CLIMB AT 500-100 FPM, STAB OUT OF TRIM LIGHT IS NOT ILLUMINATED.  COULD NOT DUPLICATE ON GROUND.  AUTO PILOT ALTITUDE HOLD CHECKS GOOD IAW B727 M/M 22-11-01. NO HISTORY.

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