>>"A suborbital space plane that can take off from an airport, fly to Tokyo, Sydney, or London in 2 hours, and land at an airport might just be something people would pay for."
> That would be an orbital space plane.
Nop, that would not be. An orbital spaceplane would be able to get from point-to-point anywhere on the globe in 45 minutes. Of course, orbital flight for surface-to-surface transportation would be astonishingly silly.
OK, so after your post, I became curious as to how close to "orbital" a spaceplane must be that can make a trip from New York to Sydney (as opposed to the suborbital flights of Shepard and Scaled Composites which travel ~100 miles). I wrote the following to XCOR:
-->Hello, I'm a follower of your work, and
congratulations on your recent record with the
EZ-Rocket. I would assume one of the markets for the
cutting edge space-plane industry is long-distance
passenger transport, say New York to Sydney or
similar. Even though a full orbit of the earth is not
required, would this vehicle have to basically reach
orbital speeds to make such a journey, or could a
sub-orbital vehicle such as yours make the trip and
not have to deal with the re-entry heat issues and
much larger thrust requirement? Thanks and good luck,<---
Their reply:
--> By definition, any vehicle whose trajectory always intersects the Earth's
surface is in a suborbital trajectory, and if it meets the other elements of
the definition, is a suborbital rocket.
Depending on how much use one makes of the atmosphere for range
extension by gliding, long-range point to point transport takes something
on the rough order of 60-80% of the velocity (or about half the specific
energy) of orbital flight. That's way harder than just reaching 100km altitudes
and a bit easier than making orbit.<---
So as I suspected, a craft that could make a flight out of the atmosphere halfway around the world, while technically a suborbital trip, basically needs orbital capability. That is an order of magnitude more difficult and impressive an accomplishment than the bottle rocket shots Rutan and XCOR may be capable of. Like I said in my e-mail to them, I wish them the best of luck, but like I said in this thread, I am far more impressed with NASA's accomplishments and rightly so.