# SDR DXTA2026072708974

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: July 23, 2026
- Submitted: July 27, 2026
- Operation: Air carrier
- Aircraft: [N790QS](https://openairdocs.org/aircraft/N790QS), registered now
- Make and model: Bombdr BD1001A10
- Aircraft serial: 20627
- Aircraft time: 11,408 hours, 6,656 cycles
- System (JASC): [2100 · Air Conditioning System](https://openairdocs.org/jasc/2100)
- Part: Bypass Valve
- Condition: Faulted
- Location: Right
- Stage of operation: CL
- How discovered: O
- Nature of condition: E, J
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/DXTA2026072708974

## Discrepancy

ON CLIMB OUT FROM KLAS PASSING 10,000FT WE GOT AN AMBER EMERGENCY EXIT CAS MSG. LEVELED OFF AT 12,000FT & RAN THE QRH CHECKLIST. IT WAS NOTED THAT AT SPEEDS ABOVE 300KTS A DISTINCT VIBRATION WAS FELT IN THE CONTROL COLUMN AS WELL AS THE FUSELAGE. SLOWED TO 290KTS AND THE VIBRATION WENT AWAY.  REMOVED RT HEAT EXCHANGER BYPASS VALVE AND REPLACED WITH CUSTOMER SUPPLIED NEW VALVE. PERFORMED SYSTEM LEAK, BLEED AND OPERATIONAL CHECK, NO DEFECTS NOTED. SERVICED HYDRAULIC TO FULL. RAN ENGINES AND CYCLE FLIGHT CONTROLS AND RT TEMP REACH AROUND 52. WORK PERFORMED IAW AMM 29-12-45.

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