SpaceShipOne Back in Action

JoeSilva writes "After a 3 month wait, Scaled Composites' SpaceShipOne is back in the skies above Mojave! Not only is it patched up from a failed landing gear, it's got a 'thermal protection system' installed. Looks like high temp insulation on the leading edges. Also they have a picture of it with 'the rocket motor for the flight 13p'. This was the 12th SpaceShipOne flight."

Comments

For those who don't know

[ferralis]

the "P" stands for Powered... looks like they're tipping their hand and the next flight will be with boost!

WOOHOO!!!

Check out the test updates here.

AFAIK, these guys are the closest to winning the X-Prize- go team!!!

Photos

[bobthemuse]

A great set of photos (hopefully soon to be mirrored) is available here.

Re:Lucky 13?

[jwriney]

Any team wanting to make an attempt must notify the X-Prize officials at least a month in advance with the launch date and location. I would assume that this information would be released with some fanfare. Since no notification has been made yet, no official flight.

That's not to say they couldn't go to space unofficially, before going for the big money; in fact they probably will, as part of their test series.

--riney

Heat shielding is minor compared to orbital craft

[Dr. Zowie]

Remember (nobody ever seems to) that getting into space is not nearly has hard as getting into orbit. We're used to descriptions of the amazing technology that is used to protect astronauts and such on re-entry -- but that amazing technology is only needed because of the enormous speeds that orbital vehicles have to attain.

The kinetic energy required to accelerate a gallon of gasoline to orbital speed is more than the chemical energy contained in the gasoline.

By contrast, "merely" lifting something up 100km doesn't require much energy at all.

So, er, no, leading-edge heat shields ought to be just fine. Fiberglass or carbon-fiber composites might even survive a flight or two without any shielding at all.

Re:Lucky 13?

[ericspinder]

Most likely they'll hit space with a lone pilot a couple of times first. Ever flight so far only has 2 in the WK and 1 in the SSO. To win the X-Prize they would need 3 people in the SSO. So far they have been playing it safe by only having just as many people as needed(as they should), I don't see any reason they'll change the play. All the test runs they are making is showing the strength of their system, if this were NASA the runs would be 6 months apart. Besides, it's not like there is any other group so close to winning the prize. Maybe some other team might just pop outta nowhere and grab that brass ring, but they would have to be awefully sneaky to do that.

Re:Needed: Improved Fuels

[Rorschach1]

Where do you get that information from? I'm not a physical chemist, but the rocketry books I've read say that chemical fuels aren't going to get much past 450 to 500 seconds Isp. The SSMEs get about 450, I think. Isp (specific impulse) is directly proportional to exhaust temperature, which is always going to be an issue in practical rocket design.

The 1970's NERVA nuclear rocket program managed to get about twice the Isp of our best chemical rockets with a decent amount of thrust. Ion drives might give you an order of magnitude improvement over chemical rockets, but they don't have the thrust to be used in launch vehicles.

The only propulsion system I've seen proposed that could realistically produce 2 to 3 orders of magnitude increase in efficiency is the Orion drive. The government doesn't like the idea of building hundreds of small, clean nukes, though. Greenpeace gets a bit riled up about it, too.

Of course, if I had my way, they'd be welcome to protest right at the launch site.

Re:Heat shielding is minor compared to orbital cra

[ThosLives]

I can't resist:

The energy content of gasoline is about 42e6 J/kg.

Orbital velocity (at the surface of the earth) is about 8000 m/s. Kinetic energy of 1 kg at 8000 m/s is 32e6 J. (That is, you need about 32 MJ/kg)

However for those who want the whole story, the parent to this is correct: to get all that energy out of the kg of gasoline, you *also* need about 2.8 kg oxygen. Gasoline-oxygen gets you about 11 MJ/kg, which is about a third of what you need to hit orbital velocity.

To get to 100 km altitude, you need only 0.96 MJ/kg, which is no problem for gasoline-oxygen.

Re:Despite what it looks like...

[captainClassLoader]

Yeah, no kidding. Bert Rutan has not one, but 3 aircraft designs displayed at the Smithsonian's National Air and Space Museum. These are the around-the-world Voyager,, and the experimental homebuilts VariEze, and Quickie.

Three people not necessary

[jmichaelg]

To win the X-Prize they would need 3 people in the SSO.

The ship only has to have accomodations for three people. The rules allow for substituting ballast for the passenger's weight and letting the single pilot go up alone. The relevant rule is

3. The flight vehicle must be flown twice within a 14-day period. Each flight must carry at least one person, to minimum altitude of 100 km (62 miles). The flight vehicle must be built with the capacity (weight and volume) to carry a minimum of 3 adults of height 188 cm (6 feet 2 inches) and weight 90 kg (198 pounds) each. Three people of this size or larger must be able to enter, occupy, and be fastened into the flight vehicle on Earth's surface prior to take-off, and equivalent ballast must be carried in-flight if the number of persons on-board during flight is less than 3 persons.