# SDR 3EJA393JS080626

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: August 6, 2026
- Submitted: August 24, 2026
- Operation: Air carrier
- Aircraft: [N393JS](https://openairdocs.org/aircraft/N393JS), registered now
- Make and model: Bombdr BD1001A10
- Aircraft serial: 20282
- Aircraft time: 5,276 hours, 4,537 cycles
- System (JASC): [2913 · Hydraulic Pump (Electric/Engine), Main](https://openairdocs.org/jasc/2913)
- Part: Pump
- Part number: 5116005
- Part serial: K0911
- Condition: Failed
- Location: Zone 400
- Part time: 1,921 hours, 1,422 cycles
- Stage of operation: DE
- 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/3EJA393JS080626

## Discrepancy

DURING DECENT INTO DJI  EXPERIENCED A VIBRATION FOLLOWED BY A CYAN RT HYD PUMP FAIL CAS MESSAGE. AS WE WERE JOINING THE FINAL APPROACH COURSE AN AMBER R HYD PUMP FAIL MESSAGE APPEARED. RAN CHECKLIST FOR THE CAS MESSAGE. DECLARED AN EMERGENCY ONCE RECEIVED THE AMBER CAS. WE ALSO NOTED A CYAN R ENG FAULT MESSAGE, FLAPS RATE LOW & AN AMBER R STARTER FAIL MESSAGE ON FINAL. TROUBLED SHOT START SYS. CHECKED RESISTANCES OF RT START CONTROL VALVE & WIRING CIRCUITS. FOUND AT PIN A OF CONNECTOR W4P6 HAS VERY UMN RESISTANCE LOW RESISTANCE. ISOLATED CIRCUITS & FOUND CIRCUIT BREAKER R/ATS/HYD SOL POPPED. DISCONNECTED HYD BYPASS VALVE ON RT PUMP RESISTANCE WENT TO OPEN. CHECKED RESISTANCE OF PUMP BYPASS VALVE GOT ABOVE 100 OHMS. RECONNECTED CONNECTOR AT PUMP RESISTANCE WENT TO 1.4 OHMS. CHECKED RESISTANCE AT PIN 1 ON PUMP TO GROUND GOT .3 OHMS SHOULD BE OPEN. REF WIRING MANUAL SEC 80-11-00. REMOVED FAULTY NR 2 HYD EDP & INSTALLED MODIFIED HYD PUMP WITH O-RING IAW AMM 29-12-01.  OPS & LEAK CHECKED GOOD.  ENGINE START SUCCESSFUL. NO FURTHER DEFECTS NOTED AT THIS TIME.

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