Do people who die in a plane crash feel a moment of major pain or is it so fast they don't know what hit them?

(Sorry for the morbid question) I had a friend in college who died in a car on fire. The truck driver who she'd collided with said he heard her screaming but an EMT I know told me that after a few seconds in a big fire like that all the nerves are dead so she really didn't feel anything. I'm not sure I believe it???