# SDR IPXA2020021435094

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: February 12, 2020
- Submitted: February 17, 2020
- Operation: Air carrier
- Aircraft: [N426UP](https://openairdocs.org/aircraft/N426UP), registered now
- Make and model: Boeing 757-24APF
- Registry model: [Boeing 757-24APF](https://openairdocs.org/model/boeing-757-24apf) (OpenAirDocs)
- Aircraft serial: 25457
- Aircraft time: 27,441 hours, 18,854 cycles
- System (JASC): [3460 · Flight Management Computing Hardware System](https://openairdocs.org/jasc/3460)
- Part: Fmc
- Condition: Malfunctioned
- 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/IPXA2020021435094

## Discrepancy

WHILE AT CRUISE FL280 REC'D AN "ATC" CHIME FOR CPDLC RADIO CHG. SUBSEQUENTLY THE FOLLOWING  INDICATIONS WERE DISPLAYED: AUTOPILOT, A YELLOW LINE THRU VNAV PATH & LNAV FMAS RED AIRSPEED INDICATOR DROP 310 KTS TO 220 KTS THEN RETURNED, VNAV KICKED OFF AND REVERTED TO ALTITUDE HOLD.REPLACED ACARS CMU IAW AMM 23-22-01. OPS CK GOOD. CORRECT SOFTWARE INSTALLED IAW ACFT SOFTWARE MATRIX VERSION 84. THIS CLEARS M698855, PLACARD REMOVED.

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