http://www.gizmag.com/terraspan-vacuum-tube-train-supersonic...
>Safety is no small concern when you're talking about speeds in excess of 4,000 mph (6,437 km/h). After all, we've all seen the wreckage that can be caused in a 60 mph (96 km/h) car crash. The kinds of tube tracks we're talking about here would have to stretch thousands of miles in order to reach their optimum level of benefit – that's thousands of miles of safety risks. What happens when an earthquake strikes and cracks the pressure seal or destroys the tube completely? A vehicle traveling 4,000 mph is going to eat up some serious distance in an emergency stop situation.
Car accidents at 50 MPH result in 80% death.
760 MPH is much much much more, considering the amount of energy needed to be dispersed grows quadratically (E = 0.5 * m * v^2)
Actual stats from Great Britain in 2008 on motorways, presumably always speed limit above 50 MPH, "6% of the total killed, 3% of total seriously injured, 5% of total with slight injuries." at least per wikipedia.
So there's about a 9 in 10 chance if you crash on a GB motorway, at least in 2008, you'll walk away without a scratch, rather than your 1 in 5 stat.
Also all minor aircraft accidents involve flying faster than 50 MPH although death from anything but fire is relatively rare. True though, that controlled flight into terrain at cruise speed doesn't usually leave many large pieces on the mountainside.
http://www.swov.nl/rapport/Factsheets/UK/FS_Speed.pdf
Though that number is always going down, because modern cars are safer than previous gens.