# SDR IPXA2026020652253

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: January 30, 2026
- Submitted: February 6, 2026
- Operation: Air carrier
- Aircraft: [N570UP](https://openairdocs.org/aircraft/N570UP), registered now
- Make and model: Boeing 747-44AF
- Registry model: [Boeing 747-44AF](https://openairdocs.org/model/boeing-747-44af) (OpenAirDocs)
- Aircraft serial: 35667
- Aircraft time: 65,663 hours, 10,777 cycles
- System (JASC): [3445 · Air Collision Avoidance System](https://openairdocs.org/jasc/3445)
- Part: Antenna
- Part number: 7514081901
- Part serial: ANE45256
- Condition: Faulted
- Location: Tcas Sys
- Stage of operation: CL
- How discovered: 9
- Nature of condition: O
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/IPXA2026020652253

## Discrepancy

AIR TURN BACK,  TCAS SYSTEM ADVISORY MESSAGE CHECK CMC PRESENT LEG FAULT.FND TCAS LOWER ANTENNA FAIL.  REPLACED LOWER TACAS ANTENNA .PFM GOUND TEST PASS.PER AMM34-45-02.SYS BACK TO NML.

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