Narrative:

Upon departure from ZZZ rwy xx just after lift off a toxic smelling odor entered the cockpit and cabin. The medical flight crew expressed much discomfort and began looking for smoke as the odor smelled of burning chemicals. I continued the departure under IFR in VMC. I was switched to departure from tower. The crew reported seeing a haze of smoke in the cabin. I immediately requested priority and turned back to ZZZ; switching back to the tower and letting them know I was coming in to land. They cleared me into runway xy where I landed without incident. I had the fire department dispatched. After landing I was cleared to fast taxi to our ramp and as I never actually saw smoke or fire. I had the crew get the extinguisher and they exited as soon as we stopped. I secured the aircraft and exited.

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Original NASA ASRS Text

Title: Pilatus PC-12 Captain reported an uneventful air return due to a fume event immediately after takeoff.

Narrative: Upon departure from ZZZ Rwy XX just after lift off a toxic smelling odor entered the cockpit and cabin. The Medical Flight Crew expressed much discomfort and began looking for smoke as the odor smelled of burning chemicals. I continued the departure under IFR in VMC. I was switched to Departure from Tower. The crew reported seeing a haze of smoke in the cabin. I immediately requested priority and turned back to ZZZ; switching back to the Tower and letting them know I was coming in to land. They cleared me into RWY XY where I landed without incident. I had the fire department dispatched. After landing I was cleared to fast taxi to our ramp and as I never actually saw smoke or fire. I had the crew get the extinguisher and they exited as soon as we stopped. I secured the aircraft and exited.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.