One study showed that hybrid models have a safetyedge over their conventional counterparts when it comes to protecting drivers and passengers from injuries in crashes.
Some aviation safety experts have questioned whether FAA has the in-house expertise to oversee the safety of cutting-edge technologies that haven't been in planes before.
For most inter-city journeys of more than two hours and less than five, rail has the competitive edge in safety, reliability and speed over both aircraft and cars.
