# SDR 9JLA2021041623531

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: April 9, 2021
- Submitted: April 16, 2021
- Operation: Air carrier
- Aircraft: [N87SK](https://openairdocs.org/aircraft/N87SK), registered now
- Make and model: Lear 45LEAR
- Aircraft serial: 317
- Aircraft time: 4,189 hours, 3,150 cycles
- System (JASC): [3400 · Navigation System](https://openairdocs.org/jasc/3400)
- Part: Fms
- Part number: 301741221
- Part serial: 775
- Condition: Fault Message
- Location: Nr 2
- Stage of operation: IN
- 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/9JLA2021041623531

## Discrepancy

THE FLIGHT CREW REPORTED THAT THE NAVIGATION SYSTEM FMS NO2 WAS UNABLE TO SYNC WITH THE FMS NO1. ARINC/WAAS TEST FAIL. THE MAINTENANCE TEAM TROUBLESHOT AND DETERMINED THAT THE #2 FMS WAS DEFECTIVE. A MODIFIED UNIVERSAL AVIONICS UNS1EW FMS WAS INSTALLED INTO THE NO2 POSITION. FUNCTIONAL CHECKS WERE SATISFACTORY AND THE AIRCRAFT WAS RETURNED TO SERVICE.

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