# SDR 2021F00142

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 6, 2021
- Submitted: August 8, 2021
- Operation: General aviation
- Aircraft: [N419MC](https://openairdocs.org/aircraft/N419MC), registered now
- Make and model: Boeing 747-48EF
- Registry model: [Boeing 747-48EF](https://openairdocs.org/model/boeing-747-48ef) (OpenAirDocs)
- Aircraft serial: 28367
- System (JASC): [2910 · Hydraulic System, Main](https://openairdocs.org/jasc/2910)
- Part: O-Ring
- Condition: Failed
- Location: Hyd System
- Stage of operation: NR
- How discovered: O
- Nature of condition: K, J
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/2021F00142

## Discrepancy

FIVE HOURS BEFORE ARRIVAL FROM LAX INTO ZAZ, ATLAS AIR MCC NOTIFIED TO SERVITEC ZAZ TEAM (SERVITEC'S APPROVAL Nº 5VCY446D)LOST OF QTY IN HYD #4. ON ARRIVAL, ENGINEERS PERFORMED T/S AND REPLACED O'RING IN UPPER PLUG OF ALTERNATE BRAKE SWITCH MANIFOLD. DURING O'RING REPLACEMENT, A HYDRAULIC LEAKAGE OCURRED.

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