Slashdot Mirror
SpaceShipOne Completes Second Test Flight
waynegoode writes "According to an article at Space.com, Scaled Composites' SpaceShipOne suborbital rocket plane made its second powered flight today. The piloted vehicle was powered by a hybrid rocket motor to over 105,000 feet. The engine burned for 40 seconds, zipping to Mach 2. SpaceShipOne is one of several projects competing for the $10 million X Prize. Slashdot mentioned yesterday that it received a license from the FAA, the first license for a suborbital rocket."
They have to get to 328,000 feet, seems like they are looking pretty good.
How about our favorite FPS gaming programmer turned rocketman John Carmack's Armadillo Aerospace?
http://www.armadilloaerospace.com
Wow, that was a big possesive noun.
"We need a fourth law of Robotics: Stop Fingering My Wife"
SpaceShipOne is the most likely winner, but Armadillo Aerospace is also trying for a launch this year, and could potentially beat SpaceShipOne.
"They redundantly repeated themselves over and over again incessantly without end ad infinitum" -- ibid.
They have to get to 328,000 feet, seems like they are looking pretty good.
I bet this one only went a third of the way because that's about as far up as they can go while still controlling the craft's attitude with control surfaces.
Power for the rest of the altitude should be no problem, since their engine seems to be working just fine. But they'll need also need their attitude control and reentry heat shielding working to go extra-atmospheric - where they can't just glide down the whole way.
So first some tests where the limits of the aircraft mode are demonstrated and debugged, followed by tests where the additonal functions are also used.
One step at a time wins the race. B-)
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
Scaled has a huge reputation in the industry. They're sort of the outsource Skunk Works. Companies like Boeing and Lockheed go to Scaled when they need something bizarre built and tested. Scaled isn't ever going to have a spot next to Boeing and Lockheed because Boeing and Lockheed are their customers.
-twb
I've been following Armadillo about every week on their news page for the past year. I like their dedication and method of building a ship.
They have however spent a lot of time dealing with engine issues. They've already had to go from a 90% peroxide monopropellent design to a 50% peroxide/methanol mixed-monoprop because FNC (one of the few companies that make 90% peroxide) wasn't willing to sell it to them. They've spent a lot more time dealing with designing the engines than they anticipated. Just goes to show, rocket engine design is not simple!
Other issues include how to get the thing back on the ground safely. They initally planned to use a big ass parachute to land it, but they found out that this really restricts them in terms of getting a launch license. Because there is a possiblity for such huge range drift with the parachute design (thus endangering public safety since it can land in a huge footprint) that they've now had to think about doing a powered landing using the engines. This of course, leaves much less room for error on landing. An alternative would be to have the pilot bail out and parachute down while the ship lands by itself, but again this adds complexity.
Although I'd love to see them win, the fact is, Rutan is way ahead of them in terms of testing and having a working prototype ship. Basically SS1 is the favorite by quite a bit as of now.
You realize that the first nonstop transatlantic flight was made by a couple of Brits, not Lindbergh. He was first to solo. I think the flight by the British really was more important historically, but you won't find it in any American textbooks.
Because it doesn't reach orbital velocity, the shuttlecock system keeps the speeds down to a reasonable level and heat shielding is minimal.
Right. Falling into the atmosphere from just above it at a moderate speed is much less heating than hitting it sideways at nearly orbital velocity.
But while you're still doing atmospheric flight you only have to deal with the friction from the airspeed you need to get your lift - and you have an atmosphere around you to dump it into continuously.
Once you "pop out" you have the additional energy of your fall back from your peak altitude to flight altitude to deal with. That's a LOT. Any excess of that over the kinetic energy of your flight speed shows up as heat in your skin, mostly in the very short time near the end of the transition from "air might as well not be there" to "thick enough to fly in". This is in ADDITION to the continuous heating of the skin by flight friction - which didn't get much chance to cool by conduction in the near-vacuum of the hump flight.
If you weren't firing your engines while up in the near-vacuum it's close to a wash - you converted flight kinetic energy to altitude, then back. So it's similar to just the air friction from cruising at the high altitude and speed. If you fired your engines in the near vacuum, the portion of that energy that went into accellerating you comes back as extra heat.
So it's not as big a problem as with a shuttle (which dumps most of its orbital energy as a couple thousand mile streak of purple ionized ceramic vapor). But it's not trivial either. (Especially since you'll be flying pretty darned fast just before you leave the effective atmosphere if you want to get very far above it.) Thus the recently added heat shielding.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way