Beechjet 400
Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 40; Flight Crew Total 2450; Flight Crew Type 1600
Troubleshooting
Inflight Event / Encounter Loss Of Aircraft Control; Inflight Event / Encounter Weather / Turbulence
Air Traffic Control Issued New Clearance; Flight Crew Regained Aircraft Control; Flight Crew Requested ATC Assistance / Clarification
Weather
We were in level cruise at FL380 after departing for ZZZ. At approximately XA35 we began to encounter what we referred to as 'light chop occasional moderate chop'. Shortly thereafter; the aircraft began to Dutch roll. Autopilot and Yaw Damper remained engaged with no indications of any equipment failure. The Dutch roll got progressively worse; and the pilot not flying; disconnected the autopilot in an attempt to help me; the pilot flying; in regaining control of the airplane. We were still unable to regain control of the aircraft with the autopilot disconnected and the pilot not flying then [advised ATC] to begin a descent. Somewhere below FL370 we were able to get the airplane stabilized and we requested to level off at FL360 to assess the situation; the aircraft; and the passengers. We still had no indications of any equipment failures at that time. Upon our assessment that the airplane and passengers were ok; we noticed that we had flown through an inversion; as the wind had shifted at least 90 degrees in direction. Based on that; and the fact that we had no indications of any failures; I re-engaged the autopilot successfully and we requested a turn direct to ZZZ where we landed without further incident.
[Report narrative contained no additional information.]
BE40 crew reported moderate turbulence encounter that caused dutch roll action and loss of control of aircraft. Flight crew was able to descend to a lower altitude out of turbulence/windshear and regain control of aircraft.