Most videos of wingsuit flyers are inherently crazy — it just so happens that is the nature of humans imitating flying squirrels.

But, a recent video by Fred Fugen and Vince Reffet (aka the “Soul Flyers”) raises the bar on that inherent absurdity. The video shows them BASE jumping from the top of a mountain and flying themselves to a mid-air landing through an open plane door.

Jumping from the top of the Jungfrau mountain in Switzerland, the crew planned and prepared for the stunt for months. They also took over 100 test flights before flying into the Pilatus Porter light aircraft.

This is certainly one of the more high-risk stunts attempted in a wingsuit that we’ve ever seen.

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