1000 Ft performance on Myth Busters.

[Husky]

They ran a rocket sled on a 1000 foot track. The MPH at the end was 618 but they didn't mention time. I'd estimate the et was appx 2 seconds. It's not DR but it was very impressive.

 

[DrRocket]

Here's an Air Force flight surgeon, Col John Paul Stapp, who proved, (Using himself as test subject the majority of the time.) that human being could withstand up to 40Gs of acceleration, provided the person has the proper equipment.

Col John Paul Stapp