Light Transport; Low Wing; 2 Turbojet Eng
Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP)
ATC Issue All Types; Deviation - Altitude Excursion From Assigned Altitude; Deviation / Discrepancy - Procedural Clearance; Inflight Event / Encounter Loss Of Aircraft Control; Inflight Event / Encounter Weather / Turbulence
Air Traffic Control Provided Assistance; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Regained Aircraft Control
Human Factors; Weather
ATC given heading for vector for weather and entered cloud with severe turbulence with down draft auto pilot disconnected; and power and pitch up with continued down draft about 1;200 ft. altitude lost and severe turbulence until aircraft was out the cloud; report it to ATC.We were vectored by ATC and we did not see the weather on the radar in IMC.
We were getting vectored by ATC to go around weather and on the final vector before the occurrence we got vectored into a cloud that began to produce moderate turbulence. We attempted to get deviations but could not reach the Controller. It was then that we experienced what we described as a severe downward wind shear that made us lose control of the aircraft and the aircraft had an immediate 4000+ ft. per minute drop in altitude. Autopilot disengaged and we found ourselves at 1800 ft. MSL and I began to slow to maneuvering speed to regain control of the aircraft. Once I did I immediately began a climb and we finally had the Controller provide deviation instructions and we exited the cloud and the turbulence subsided.We had nothing on radar and thought the Controller was guiding us away from thunderstorms but he was not seeing it as well.
Flight crew reported a loss of aircraft control in severe turbulence.