# SDR IPXA2023122752513

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: December 26, 2023
- Submitted: December 27, 2023
- Operation: Air carrier
- Aircraft: [N463UP](https://openairdocs.org/aircraft/N463UP), registered now
- Make and model: Boeing 757-24APF
- Registry model: [Boeing 757-24APF](https://openairdocs.org/model/boeing-757-24apf) (OpenAirDocs)
- Aircraft serial: 28267
- Aircraft time: 37,722 hours, 19,985 cycles
- System (JASC): [3417 · Air Data Computer](https://openairdocs.org/jasc/3417)
- Part: Indicator
- Part number: UNKNOWN
- Part serial: NA
- Condition: Inoperative
- Location: Airspeed
- Stage of operation: CL
- How discovered: 9
- Nature of condition: O
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/IPXA2023122752513

## Discrepancy

**ATB - EMERGENCY DECLARED**LOST CAPT AIRSPEED ON TAKEOFF, PERFORMED UNRELIABLE AIRSPEED V LIST, EICAS SHOWED RUDDER RATIO AND MACH IAS.ON CLIMB OUT F/O'S AIRSPEED DROPPED SIGNIFICANTLY, GOT F/O'S STICK SHAKER. AIR TURN BACK NOTE: RUDDER RATIO EICAS MSG ADDRESSED ON LINE ITEM #4. CW CAPT'S AND F/O'S ADC BITE TEST PER FIM 34-12 FAULT TREE 813, FIG 109. NO DEFECTS FOUND, PURGED LINES FROM CAPT'S AND F/O'S ADC PER AMM 34-11-01-167-004 TO PITOT TUBES, REMOVED ALL   DEBRIS BLOCKING BOTH PITOT TUBES. CW PITOT PROBE TEST OF CAPT AND FO'S PITOTS. POS CK NORMAL PER AMM 34-11-01-755-033.

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