I think that Oso may have been referring to the Gerry Anderson Supercar, from the UK early 60s TV series, rather than the Moller Skycar. Rumour has it that it can perform close to the FS2002 maximum speed of Mach 3.
Don't forget Concorde, of course! That does Mach 2, but is not all that manoeuvrable around landmarks!
To increase speed further, don't forget that you can speed the sim up to 16 times, without losing the autopilot control.
