PC-12 pilot reported experiencing spatial disorientation and loss of aircraft control shortly after takeoff entering IMC conditions. The Captain took control and stabilized the aircraft.

Narrative

Spatial Disorientation Incident. On a flight yesterday from ZZZ to ZZZ1; I encountered a moment of spatial disorientation during takeoff as the Pilot Flying (PF) in a PC-12; Aircraft X. The Captain was serving as the Pilot Monitoring (PM). The departure weather included a ceiling of 400 ft overcast with tops around 700 ft.Departing from Runway XX at ZZZ; we quickly entered IMC conditions. Upon achieving a positive rate of climb and adequate airspeed; I called for the gear to be retracted and flaps zero. As we continued climbing; I focused on managing airspeed for an IAS mode activation. At this point; I experienced a complete loss of situational awareness - my spatial senses became unreliable; and I lost track of my flight director and instrument scan.The Captain promptly intervened; first announcing; 'Get back on heading.' As I struggled to regain focus; he added; 'Follow the flight director;' followed immediately by 'My flight controls.' Around the same time; the 'Don't sink rate' annunciator activated; further compounding the situation.With the Captain now flying; he stabilized the aircraft on the correct heading. Shortly after; the controller issued instructions to switch over to departure frequency. As we broke through the cloud tops into VMC conditions; situational awareness improved; and we established communication with Departure. The remainder of the flight was uneventful. Following this spatial disorientation incident; I recommend a comprehensive review and retraining on instrument scan techniques; automation management; and spatial disorientation recovery procedures. The retraining should be conducted using the PC-12 aircraft and its associated systems to replicate the conditions encountered and ensure proficiency in real-world operations.IMC Departure Simulations: Practice takeoff and initial climb transitions into IMC; emphasizing proper instrument scan discipline and flight director usage. Spatial Disorientation Recovery: Recognize early signs of disorientation and practice recovery techniques; including reliance on flight instruments rather than physical sensations. CRM and Pilot Monitoring: Reinforce effective Crew Resource Management (CRM); focusing on timely communication between PF and PM to mitigate errors. Automation Management: Practice proper use and verification of IAS mode activations and other autopilot settings to reduce workload during critical phases of flight.