# SDR 99UAL900416

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 7, 1999
- Submitted: March 26, 2000
- Operation: Air carrier
- Aircraft: N7251U
- Make and model: Boeing 727222
- Aircraft serial: 21398
- Engine: Pwa JT8D15
- System (JASC): [3230 · Landing Gear Retraction/Extension System](https://openairdocs.org/jasc/3230)
- Part: Sequence Valve
- Part number: 1U10851
- Condition: Leaking
- Location: Lt Mlg
- Stage of operation: LD
- Nature of condition: K, J
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/99UAL900416

## Discrepancy

ON GEAR EXTENSION AIRCRAFT LOST HYDRAULIC SYSTEM A.  BOTH PUMPS RAN TO ZERO HYDRAULIC FLUID QUANTITY.  *S/D*  REPLACED NR 1 AND NR 2 ENGINE DRIVEN HYDRAULIC PUMPS AND REPLACED LT MLG LOCK OPERATED SEQUENCE VLV PER MAINTENANCE MANUAL.  PERFORMED NORMAL RETRACTION AND MANUAL EXTENSION TESTS, NO IRREGULARITIES FOUND.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.