Reply to post: Re: Perhaps?

Re: Perhaps?

@Milton: "The Virgin stuff is as silly and pointless now as it was five years ago. In principle it's the same as a 1970s era Boeing 707 Vomit Comet, just a ballistic arc to simulate zero-g: doesn't go anywhere, doesn't orbit, doesn't produce any tech relevant to real space travel.

If rich idiots want an "Astronaut" Merit Badge for being fireworked up to an arbitrary altitude, more fool them."

The Kármán line, above which SS2 is designed to travel, is by definition the limit beyond which it's impossible for anything to fly aerodynamically. That's why it's generally accepted as the altitude at which "space" begins. Practically speaking, nothing can fly remotely near that altitude using aerodynamic lift.

Note also that a "vomit comet" trip involves a repeated pattern of climb and dive to give periods of (typically) 25s apparent weightlessness followed by perhaps twice that time pulling close to 2g, the cabin rotating in pitch all the time.

This all happens well inside the atmosphere at ordinary aircraft heights, in an aircraft cabin without much in the way of windows: you experience flight noise, no view, and the process often causes nausea (the clue is in the name "vomit comet").

https://en.wikipedia.org/wiki/Reduced_gravity_aircraft

Apparently, "one third [become] violently ill, the next third moderately ill, and the final third not at all." Vomiting is referred to as "ill".

What Virgin Galactic will offer is very different and akin to Alan Shepard's 1961 trip as the first American in space (Mercury-Redstone 3/Freedom 7) - but with a smoother ride and much better facilities.

What you'll get from Virgin Galactic is a jet flight up to about 50,000 feet (15,000m) with the space ship slung beneath a conventional jet aircraft, followed by release and a rocket powered supersonic flight (pulling perhaps 3.8g) out of the atmosphere into space, reaching about 110km (361,000 ft), with view ports through which the passengers can see the blackness of space, the curvature of Earth, and a view for maybe a thousand miles around.

Once the engine's cut, Branson's ride will offer several minutes (not a fraction of a minute) of free fall during which passengers will be able to float around and enjoy the view. Most people experiencing zero g in this sort of way don't get sick.

http://www.parabolicarc.com/2009/12/07/spaceshiptwo-whiteknighttwo-specs-flight-profile/

Certainly one might reasonably argue that the Virgin Galactic sub-orbital ride business is silly and pointless and you might well be right. But the altitude they're aiming for isn't arbitrary, and the ride's going to be a lot more substantial than a vomit comet trip.