# SDR P5CA0501340

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: April 17, 2005
- Submitted: April 20, 2005
- Operation: Air carrier
- Aircraft: [N509MC](https://openairdocs.org/aircraft/N509MC), registered now
- Make and model: Boeing 747230B
- Aircraft serial: 21221
- Aircraft time: 113,141 hours, 21,512 cycles
- System (JASC): [2297 · Auto Flight System Wiring](https://openairdocs.org/jasc/2297)
- Part: Wire
- Condition: Miswired
- Location: Autopilot
- Stage of operation: CL
- How discovered: O
- Nature of condition: W
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/P5CA0501340

## Discrepancy

A-AUTOPILOT TOC F/L 320 SELECTED ALT HOLD A/C WENT 100 FT HIGH THEN DESCENDED TO 31500.  DISENGAGED AUTOPILOT HAND FLEW A/C BACK TO F/L 320.  SELECTED AUTOPILOT-B ALT HOLD.  FOUND ALT HOLD JUMPER WIRES FROM AUTOPILOT-A PITCH COMPUTER AND NR 1 CADC PIN 64,65 SWAPPED.  SWAPPED WIRES PER WDM 22-12-13.  PERFORMED ALT HOLD SYSTEM PER MM 22-10-00.

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