# SDR 97ZZZM649

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: February 22, 1997
- Submitted: March 26, 2000
- Operation: Air carrier
- Aircraft: N485EV
- Make and model: Boeing 747 212B
- Registry model: [Boeing 747 212B](https://openairdocs.org/model/boeing-747-212b) (OpenAirDocs)
- Aircraft serial: 20712
- System (JASC): [3231 · Landing Gear Door Retract Section](https://openairdocs.org/jasc/3231)
- Part: Sequence Valve
- Part number: 26702887
- Condition: Failed
- Location: Nlg
- Part time: 79,517 hours
- Stage of operation: CL
- Nature of condition: E, J
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/97ZZZM649

## Discrepancy

JED - AFTER T/O, ON L/G RETRACTION, WHEN GEAR HANDLE WAS PLACED TO OFF.  ENCOUNTERED WIND NOISE AND VIBRATION FROM N/G AREA.  DOOR OPEN INDICATIONS, PRIMARY/SECONDARY N/G DOOR OPEN LIGHT ILLUMINATED ON AND OFF TOGETHER, ACCOMPANIED BY HYDRAULIC PERSSURE BUMPS.  ALL INDICATIONS NORMAL ON GEAR EXTENSION.  REPLACED NOSE GEAR OPERATED SEQUENCE VALVES.  REFERENCE EIAA970034.

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