# SDR IPXA2026101188731

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: October 10, 2026
- Submitted: October 12, 2026
- Operation: Air carrier
- Aircraft: [N573UP](https://openairdocs.org/aircraft/N573UP), registered now
- Make and model: Boeing 747-44AF
- Registry model: [Boeing 747-44AF](https://openairdocs.org/model/boeing-747-44af) (OpenAirDocs)
- Aircraft serial: 35662
- Aircraft time: 65,817 hours, 10,453 cycles
- System (JASC): [3350 · Emergency Lighting](https://openairdocs.org/jasc/3350)
- Part: Battery Pack
- Part number: 20131A
- Part serial: 56169
- Condition: Inoperative
- Location: Zone 200
- Stage of operation: IN
- How discovered: C
- Nature of condition: L
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/IPXA2026101188731

## Discrepancy

FOUND UPPER DECK EMERGENCY LIGHT M4915, L1533, L5733,5767 INOPERATIVE.  IAW AMM 33-51-04-002-009-001, 33-51-04-402-012-001, AND 33-51-04-902-001-001 REV.117 AND SSM 33-51-01 REV.48 REPLACED THE EMERGENCY LIGHT POWER SUPPLY M5169 AND THE BATTERY ASSEMBLY, AND PERFORMED THE POWER SUPPLY TEST, RESULT WAS SATISFACTORY.

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