Talk:SpaceShipOne

Where did we get "The energy requirements of true orbital space flight are in the order of 33 times as much as a SpaceShipOne ascent."? I suspect this neglects atmospheric drag. --Doradus 18:07, Oct 4, 2004 (UTC)

This is the energy which must be imparted to the orbiting mass: For a rocket the fuel and oxygen (and their tanks) must be accelerated as well and so the energy requirement is actually more than the factor of 33 identified.

Yes, you're talking about the Tsiolkovsky rocket equation. I'm talking about the fact that air resistance decreases exponentially with altitude, so if you neglect air resistance, then you'll underestimate the fuel required by the low-altitude portion of the flight. --Doradus 23:46, Oct 5, 2004 (UTC)

If you can model the size and shape of the vehicle and take height release into account to estimate the air resistance, please add it in to the energy requirement in the document.

Yeah, well, I can't, so this is just idle speculation for the time being. --Doradus 01:06, Oct 7, 2004 (UTC)

Can't we just use the wording "net energy requirements" to avoid the intricacies of air resistance and fuel transportation? After all, the paragraph is only meant to make clear that orbiting is much more difficult than just reaching the height. My proposal: "Although impressive, the achievements of SpaceShipOne are not comparable to those of orbiting spacecraft like the Space Shuttle. Accelerating a spacecraft to orbital speed requires about 32 times as much net energy as lifting it to a height of 100 km." --Daniel

I like it. I've put it in the article. --Doradus 00:35, Oct 10, 2004 (UTC)

Thanks! After double-checking the facts I suggest a small correction: Low Earth orbit speed is a bit less than 8 km/s, so the ratio between kinetic and potential energy (at 100 km) is closer to 31. I think "about 30 times as much..." would be sufficiently exact to express what you mean. --Daniel

You don't like "over 30"? -Doradus

(Doradus) Recently, the phrase "which is powered by rubber and laughing gas" was deleted. However, the phrase is correct. Can the information be reworked into the article?

It's probably more appropriate on the Tier One page, where it is mentioned, although they use the equivalent term nitrous oxide (in two different places) for laughing gas. Jwolfe 09:38, 26 Oct 2004 (UTC)

I removed a link to a commercial site. I'm not sure of the Wiki rule, but no encyclopedia I ever saw had ads in it. -tm

Maybe a link to the wikipedia page on Private spaceflight would help. Could someone do that? I don't know how to.