# SDR UIEA2019120635987

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: December 3, 2019
- Submitted: December 6, 2019
- Operation: Air carrier
- Aircraft: [N657GT](https://openairdocs.org/aircraft/N657GT), registered now
- Make and model: Boeing 767281
- Aircraft serial: 23018
- Aircraft time: 61,508 hours, 44,024 cycles
- System (JASC): [3417 · Air Data Computer](https://openairdocs.org/jasc/3417)
- Part: Adc
- Part number: 4040800906
- Part serial: 89081846
- Condition: Malfunctioned
- Location: Right
- Stage of operation: CR
- How discovered: O
- Nature of condition: O
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/UIEA2019120635987

## Discrepancy

LEAVING FL410 FOR FL390, CAUTION MSG IAS DISAGREE WAS DISPLAYED ALONG WITH L & R ENG EEC, AILERON LOCKOUT APPEARED, & RUDDER RATIO. F/O A/S INDICATION DECREASED AS WE DESCENDED, AND PASSING FL250, THE F/O A/S INDICATION RETURNED TO NORMAL.(<P>PERFORMED PITOT HEAT TEST IAW AMM 30-31-00, NO DEFECTS NOTED. PERFORMED F/O'S PITOT SYSTEM LEAK TEST IAW AMM 34-11-00, NO DEFECTS NOTED. REMOVED AND REPLACED RIGHT ADC IAW AMM 34-12-01, OPS CHECK GOOD.<BR /></P>)

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