X Prize Race Heats Up

evenprime writes "Armadillo Aerospace have already done a drop test, and Burt Rutan's company Scaled Composites did a second flight test of their launch plane/spacecraft combination on July 3. SC haven't posted the results yet, but when they do you will find them here. Sadly, PanAero doesn't appear to be doing that well. Although I like their "Junkyard Wars" technique, it doesn't look stuffing rockets in the back end of a business jet will build a legitimate contender."

Comments

Armadillo

[tra2499]

It's interesting to note that Carmack, with Armadillo Aerospace, is taking more of an Open-Source approach to the X-Prize by participating in mailing lists and discussing various aspects of his designs with others in the rocketry community. While he's not going full-disclosure, he's at least sharing a lot more than Rutan.

I'm cheering for Armadillo.

Re:Armadillo

[tra2499]

I don't disagree about Rutan's chances vs. Carmack's. Rutan has quite a lead. Even Carmack has commented on Rutan's chances.

I think you might have read too much into my comments. I didn't say I thought Carmack was likely to win because of his approach. I said I was cheering for him.

Re:tumbling

[Flounder]

If not a "junkyard wars" approach, it is an extremely optimistic design. I would expect the wings to rip out at the roots when they light up the rocket motors.

The article describes that the rocket motors would be incremently ignited. IANARS, but I would assume this would lessen the stress on the wings. However, I would be interested to see how they handle re-entry. The frigging space shuttle burned up, why wouldn't a modified LearJet?

Re:tumbling

[tra2499]

It's not necessarily the sudden shock that makes parts separate themselves from each other. The airframe was rated to 0.8 Mach. Okay, let's assume that the FAA is being their usually pessimistic selves when it comes to airframe ratings and that it can sustain twice that much for a short duration. The speed of sound (Mach 1) is roughly 780 mph. If the airframe is capable of short bursts of 1.6 Mach, then I can't really see it surviving 2.97 Mach.

Once they hit transsonic, they will undergo a severe amount of turbulence. The longer they spend in the transsonic region, the bigger danger to those long, thin wings.

Are Competitors Building Dead-End Technology?

[reallocate]

I don't mean to demean any of the efforts, and all that cash is an obvious incentive. But, are any of the competitiors building something that isn't dead-end technology?

Consider: Rutan and others plan to boost a more-or-less conventional aircraft to a few times the speed of sound, coast to altitude, and glide back. (You can't just put a bigger firecracker in the back, remember. You need life-support, navigation, communications, and, especially, safe passage through re-entry.)

So, one of them bags the X-Prize, but in the end you still have a vehicle with a maximum velocity of 1500-2500 mph. That's a long way from the 17,000 mph needed to reach and sustain orbit.

Are any X-Prize competitors building something that can be the basis of a realistic orbital vehicle?

Re:Are Competitors Building Dead-End Technology?

[seanthenerd]

Actually, I read in a PopSci article (right here) that Rutan does have plans for the SpaceShipOne/WhiteKnight, but that he wants others to build and commercialize them:

Rutan's historical model is Wilbur Wright's tour of France in 1908, which sparked tremendous growth in the industry. Rutan wants SpaceShipOne to kick-start a similar burst of innovation. Hence his ambitious post-X-Prize testing and demonstration plan: Fly every Tuesday for five months, 20 flights in a row on schedule, to determine the system's cost and reliability. Though he envisions everything from 10- passenger suborbital tour buses to a giant White Knight that uses eight 747 engines to launch a 300-ton spacecraft, Rutan says those are for others to build: "The Wrights didn't build the world's first airliner--they didn't need to," he says. "I hope people don't expect me to certificate a spaceship and offer rides. I want to be doing something more exciting by then."

Go, Burt!

Re:tumbling

[AdEbh]

The problem is that the airframe and the wings are NOT designed to withstand the necessary stress of escape velocity.

Correct, yet only shows that you did not follow the link & read. If you had, you know that their flight plan calls for sub-orbital speeds. Sub-orbital speeds are, as the name implies, slower than orbital speed. Which in turn even slower than escape velocities, which for some strange reason your talking about. Escape velocity is the speed at which you totally escape (hence the name) the gravitational pull of a body (i.e. Earth).

If you look at the successful "space plane" type vehicles that NASA or any other big research team has developed, you'll see that it required designs that looked more like a rocket than an airplane to get anything anywhere near the edge of space.

That's because they are designed for orbital speeds. Take the space shuttle. It has not only to flight at sub-sonic & super-sonic speeds, it also has to flight at what is called ultra-sonic speeds. At ultra-sonic (> mach 15 if I remember correctly, though someone will know doubt correct me) the aerodynamics of the shuttle change again. The designers had to take this all into account. That's why the shuttle handles little better than a brick while landing. Indeed to call what the shuttle does during re-entry flighting is being rather kind.

I would expect the wings to rip out at the roots when they light up the rocket motors.

You did not read much did you? They slowly increase the angle of accent as they increase trust & altitude. They only hit mach 2.97 at an altitude of 55 km. Thus the wings are not exposed to the range of forces that you seem to be imagining.

No, where the wings will face the most stress is in re-entry. It looks like they may have not full worked out all the details for this bit as they are bit sketchy on the details.

Re:Wanna fly it?

[hayesjaj]

Yes, it is more realistic, but it still needs work. From an experienced pilot's point of view, out of the box, X-Plan isn't as "real" as M$ Flightsim 2002 Pro (I'm sorry, but I did a snap roll in a 747 at 250 knots in the new xplane beta out of the box...that won't happen) . If you have some time (and the knowhow) to tweak it, it can really rock though. It is way more customizable and the graphics are much prettier. They need to add some more joystick support though...our setup here uses 6 usb joys for the throttle quad, yoke, pedals and switches. Xplane won't handle that yet. Here's hoping.