# SDR ASAA2020012832026

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: January 28, 2020
- Submitted: January 31, 2020
- Operation: Air carrier
- Aircraft: [N530AS](https://openairdocs.org/aircraft/N530AS), registered now
- Make and model: Boeing 737890
- Aircraft serial: 36578
- Aircraft time: 38,243 hours, 11,240 cycles
- System (JASC): [3412 · Outside Air Temperature Indicator/Sensor](https://openairdocs.org/jasc/3412)
- Part: Probe
- Part number: 102AH2AG
- Condition: Faulted
- Location: Lt Tat
- Stage of operation: CR
- How discovered: O
- Nature of condition: J
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2020012832026

## Discrepancy

ABOUT 45 MIN INTO FLIGHT, A/T LIM ANNUNCIATED AND VNAV DISCONNECTED. REF PREVIOUS WRITE-UPS ON LOG PAGE 12089346 AND 12089355. WE ALSO LOST ETA AND FUEL ESTIMATES ON ALL FMC PAGES. AT 15,000 FEET ON DESCENT, ALL NAV FUNCTIONS AND FMC INDICATIONS RETURNED TO NORMAL FOR THE REMAINDER OF THE FLIGHT. GROUNDED - YES. REF TSR704688 REMOVED AND REPLACED TAT PROBE REF B737-800 AMM 34-21-06, OPS CHECK GOOD. ACCOMPLISHED LEFT AND RIGHT FMC BITE REF FIM34-61 TASK 801, OPS CHECK GOOD. ALSO ACCOMPLISHED FIM 34-61 TASK 824 ADIRS INPUT FAULT ISOLATION, NO FAULT FOUND. ACCOMPLISHED FIM 34-21 TASK 801 IRS BITE, NO CURRENT FAULTS.

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