Privately Funded Manned SpaceCraft Reaches 62 Miles

It doesn't "re-enter" like the space shuttle, it just falls back down. It goes up faster than it comes down, about Mach 5.5. It is constructed to withstand those Mach numbers.

Just curious; what looks "flimsy" to you?

just out of curiosity, what altitude does the space shuttle orbit at? the space station? mercury/genmini/apollo? 62 miles is sub-orbital? correct? at what altitude does suborbital become orbital? would being orbital versus suborbital mean you would need a heat shield upon recovery?

I'm asking cuz I don't know....

shockie B)

Remember, since Spaceship One just went up and down it never reached orbit, so it's going much slower (about 4200mph) than the Shuttle. The Shuttle needs all that shielding because it's going 17,200mph (give or take a little, depending on altitude) while it's in orbit. Spaceship One is more like the X-15 than the Shuttle. When (not if) Mr. Rutan goes for orbit, I expect he'll need a much different vehicle with significantly more thermal protection.

Mark E. Hamilton NAR #48641-SR

More to do with speed than anything else....in order to achieve orbit you must go a lot, lot faster...which means that you reentry a lot, lot faster.... speed+friction= heat heat...so braking into the atmosphere from orbital speeds generates a heck of lot more heat than a suborbital lob.

Koen

IIRC, the shuttle orbits somewhere around 100-150 miles high.

I don't know, someone else will have to answer this part.

Theoretically you could orbit at any height, as long as you were going fast enough and were high enough to clear any obstacles such as mountains. Trouble is, orbit requires high speed, and the lower you orbit, the faster you have to go to avoid hitting the ground. (An orbit is basically "falling", except there's so much horizontal movement that you arepast the horizon before you can reach the ground.) Anyway, at those kinds of speeds, the atomsphere is a major problem.

The main difference between an orbital flight and a suborbital flight is the speed. Orbital = really really fast, and that means you'll generate a lot of heat when you hit the atmosphere.

As someone else mentioned, Spaceship One only reached Mach 5.5. Low Earth orbit requires several times that much speed.

The shuttle flight control design specifies 400000 ft. (just under 76 miles) as "entry interface" - this is the altitude above which the vehicle is assumed to be in "effective vacuum" and aerodynamic effects can be neglected as being too small to be significant.

-dave w

Outer space :)

Well, "orbital" is not really an altitude. Its an instantaneous tangential velocity in a gravitational field where the centripetal acceleration is equal to the local gravitational acceleration. In orbiting the Earth, you "fall" due to gravity at the same rate the curved surface of the Earth in front of you is falling away. You could orbit at any altitude, even a few feet AGL, but aerodynamic drag (and mountains) are issues. Manned missions are usually in a Low Earth Orbit from around a 100 to 1,000 miles up, most less than 400 miles. Apollo went substantially beyond LEO. In LEO, you are moving much faster than SpaceShipOne did in it's simple ballistic trajectory; 17,000 mph compared to around 4,000(?) mph.

Any orbital flight, or high speed sub-orbital flight (ICBM), re-entry would require some heat protection. Unless you had a massive retro-rocket to slow you down to the point that heat shielding wasn't required.

Heat shield is required when you hit the atmosphere at high speed. SpageShipOne does not do so, thus it doesn't need the heavy heat shield. Heard Rutan make a comment about that on the news. It eliminates one point of failure.

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

Most orbital manned spacecraft have been in the 150-250 mi range, i.e. Low Earth Orbit. IIRC the record was from the Gemini days when they got up to

You can find a plot of the ISS height over time at

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

Doesn't matter. Your motors will never be certified there either :-)

Bob Kaplow NAR # 18L TRA # "Impeach the TRA BoD" >>> To reply, remove the TRABoD!

I am pretty sure they will be certified there first, Tripoli will ascimilate the club and promptly decertify them.

Outer space is outside the influence of a planet and its moons, is it not?

Jerry

IIRC, "outer space" is one of those popular terms that has different meanings in different contexts. Outer space could be outside of your mind, or outside of your skin, or whatever is vaguely beyond earth's atmosphere, or beyond the moon's orbit around the earth, or beyond earth's orbit around the sun (away from the sun), or vaguely beyond our solar system (interstellar space), or ...

But it sounds snappy when read from the paper :-)

I read that they were off by 22 miles, but still managed to land at the planed site, so I'd say they have enough crossrange.

Alan

I meant to say they planned no boost crossrange of note, not that they have insufficient crossrange on glide landing. In fact on glide landing they do have significant crossrange.

Jerry

But isn't there both "space" and "outer space"?

There is SOME atmosphere to about 600,000 feet. Maybe more.

The Air Force says 50 miles and FAA says 62 miles for "space". Not "outer space".

Jerry

My personal favorite description of space may not have any relevance here but it does come from that Beacon of Science Fact TV show ....Gilligans Island.

Skipper: "Gilligan, there are 3 kinds of space, The space up there, the space down here .... and the space between your ears!" Gilligan: "Oh yeah Skipper! I only know one thing about space...You take up more of it than me!"

Sorry ....couldn't help myself.

Mark A Palmer TRA 08542...L3

So, "Space Aliens" are different from "Outer Space Aliens"......