I have witnessed quite a few bus accidents. I have a CDL and drive a bus just about every week. I have even rolled one on its side before with 20+ children inside and NO INJURIES believe it or not. The state fixed the caving asphalt, 4 ft deep ditch with no guard rail, and dangerous road 2 days before the case went to trial. You should have seen the look on the DA's face when I rolled out my photos.... I digress.
Once you find out that the lady crossed the centerline and hit the bus just about head on, it makes sense why the car came apart. You got F=MA for sure, but now double it if they are heading at each other. Holy cow
Daniel JessupLancaster, California
aka "The Hot Rod Reverend" 
check out the 1955 Ford Fairlane build at www.hotrodreverend.com