The scene starts moments before Ayrton Senna crashes on May 1st, 1994 on Imola's Tamburello corner. We see him driving his car from cockpit perspective (on-board camera). Then he crashes against the wall. There's no movement in the car.
Voice of Prof. Sid Watkins (F1 Doctor): We got him out of the cockpit. Got his helmet off. Got an airway into him. And I saw from his neurological signs, that it was going to be a fatal head injury. And then he sighed and his body relaxed. And that was the moment, now I'm not religious, that I thought his spirit had departed.
Senna is carried into the trauma helicopter and flown away.
Even at racing speed Tamburello is not a corner that you would make a mistake on. Something on the car would have to go wrong. Maybe the power steering failed. Maybe it was the tire temperatures that made the car skate straight off the road. I will always be a mystery.
Ayrton ran out of luck. He did not have a broken bone in his body. He did not have any bruising. If that piece of assembly would've gone 6 inches higher or 6 inches lower he would've walked back to the paddock.