Is achievingorbit that easy?

[jacobmuller]

Originally Posted by Brett

Only if its maximum airspeed exceeds circular-orbit velocity. Once the air gets thin enough that you can exceed Air Speed then the wings stop providing lift.

According to Spaceships p. 35 maximum airspeed is 2,500 m.p.h times the square root of acceleration in gees (for a streamlined spacecraft). Orbital speed is 5.6 miles per second, or 20,160 m.p.h. So you need 65 gees of thrust to fly at orbital speed.

Would making local gravity the cutoff point for a relaunchable vehicle, and delta-v for escape velocity the fuel minimum, be a solution ie can you leave Earth orbit with 1g thrust and 7+mps of delta-v? Although that would contradict pg37 "Getting into Space" 2nd paragraph, last line: "or it
must be winged (in atmosphere)". But, if the book is wrong, it's wrong.

Is this part of Spaceships wrong or merely oversimplified?