I heard that they went off a freeway overpass and the car landed on it's top. 90 feet is not that far. If the average car is about 12 feet long then 90 feet is only 7.5 car lengths. If you are doing 90 mph on the freeway and the herion you just took kicks in and you set the cruise control and crawl into the back seat for a little nap it is very possible.
My dad always told me if you are getting a hummer while the car is moving make sure youre the one driving!
PHATBOY