# SDR AALA20120308018

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: March 8, 2012
- Submitted: March 9, 2012
- Operation: Air carrier
- Aircraft: [N479AA](https://openairdocs.org/aircraft/N479AA), registered now
- Make and model: Doug DC-9-82
- Registry model: [Doug DC-9-82](https://openairdocs.org/model/mcdonnell-douglas-dc-9-82) (OpenAirDocs)
- Aircraft serial: 49654
- Aircraft time: 67,540 hours, 35,609 cycles
- System (JASC): [3417 · Air Data Computer](https://openairdocs.org/jasc/3417)
- Part: Adc
- Part number: COM7065
- Condition: Failed
- Location: Cockpit
- Stage of operation: CL
- How discovered: O
- Nature of condition: G
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/AALA20120308018

## Discrepancy

AT ABOUT 300FT AGL AFTER TAKEOFF, F/O`S CADC FAILED WITH FLAGS IN AIRSPEED AND ALTIMETER AND BOTH FLIGHT DIRECTORS FAILED.  FOUND C/B F12 POPPED.  PLACED BOTH CADCS ON NR 1 AND F/O`S INSTRUMENTS BEGAN TO INDICATE NORMAL.  ALTITUDE SELECT WINDOW FLIGHT GUIDANCE PANEL WAS BLANK, AUTOTHROTTLES WOULD NOT TURN ON.  SWITCHING FROM AP1 AND AP2 DID NOT HELP.  ON FINAL APPROACH 5 MINS LATER FLIGHT DIRECTOR BEGAN TO WORK BUT AUTOTHROTTLES WOULD NOT ENGAGE.  BOTH FMAS WENT BLANK AND AFTER 2 MINUTES SELECT WINDOW BEGAN TO WORK.  ON FINAL ALL FMA WINDOWS WORKED.  FOUND NR 2 CADC BAD.  REPLACED NR 2 CADC AND CHANGED CIRCUIT BREAKER FOR NR 2 CADC.  ALL TEST CHECKED OK.

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