# SDR CALA2026102220514

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: October 18, 2026
- Submitted: October 22, 2026
- Operation: Air carrier
- Aircraft: [N27724](https://openairdocs.org/aircraft/N27724), registered now
- Make and model: Boeing 737724
- Aircraft serial: 28791
- Aircraft time: 84,077 hours, 31,257 cycles
- Engine: Cfmint CFM567B242
- System (JASC): [2211 · Autopilot Computer](https://openairdocs.org/jasc/2211)
- Part: Computer
- Part number: 4082499902
- Part serial: 98020296
- Condition: Faulted
- Location: Flt Control
- Part time: 79,584 hours, 29,387 cycles
- Stage of operation: CL
- How discovered: O
- Nature of condition: N
- Precautionary procedure: B, A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/CALA2026102220514

## Discrepancy

NORMAL TAKEOFF,  AT 500FT LOST BOTH FLIGHT DIRECTORS,  ATC GAVE CLIMB 28K ALTITUDE, WINDOW WENT TO 50K & ENTIRE MODE CONTROL PANEL FROZEN.  HAD A LOUD ALTITUDE DEVIATION HORN GOING OFF COULDN`T SILENCE.  CAPT HDG SELECTOR ON MFD WAS ABOUT 180 DEG DIFFERENT THAN 1ST OFF.   PERFORMED MODE CONTROL PANEL TESTS IAW FIM 22-11, TASK 803.  FOUND PIN FAULT J1A-F01 FCC B.  MCP INTERACTIVE TEST FOUND PIN FAULT J1A-K06 & J1A-J06 FCC B.   REPLACED MCP IAW AMM 22-11-34, NO HELP, SLAVED IN NEW FCC A & B IAW AMM 22-11-33, NO HELP, SUSPECT MCP BAD FROM STOCK DUE TO ADDITIONAL FAULT MESSAGES. INSTALLED ORIGINAL MCP, INSTALLED KNOWN GOOD PART IN FCC B LRU, TEST PASSED.

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