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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.
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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.
I believe you are thinking of the X-43A Scramjet test vehicle.
Yes. The da Vinci project looks to be making an announcement on the date of their attempt (the launch site has already been stated) on the 16th.
They have reaction control and heat shielding on the craft as of present. The heat shielding was recently added.
Except that the wrights spent most of the rest of their career suing other people over patents. Everyone else continued innovating despite them. But I am sure you are referring to the good part where they were building aircraft out of their bicycle shop. :)
According to the article, *COUGH COUGH RTFA COUGH*, Scaled has been keeping largely mum so far but has admitted that the flight did occur and that post flight handling analysis is going on. Expect a website update in a day or two.
If you can finish in 25 seconds, you can always rent out the Vomit Comet, an airliner built for weightlessness training that flies alternating climbs and dives.
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.
No it is easy to build rocket engines, dealing with all of the retarded govt regulations is hard.
I have what I think is a innovative design for a new engine but I cannot try it. It requires aluminum powder and you have to sell your soul to the govt and jump through a thousand hoops just to get something simple like aluminum powder. If I even attempted to build a test engine the damn feds would probably be all over me accusing me of attempted terrorism.
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There are some images on RLV News . And there is also a story on space.com. Everybody in mojave must have seen and heard this.
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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
So it really is a space craft that just does not have enough delta-v to make orbit.
...Has to be the understatement of the year. Yes, sub-orbital spaceflight addresses many of the technical challenges of orbital spaceflight, however it doesn't address the only hard one. Reaction control and the aerodynamics are really rather straight forward. This project does not address the thermal control issues of orbital flight, as the heat loads are no where near what would be encountered during re-entry from orbital velocity. Moreover, they are using a solid propellant rocket motor. They would have to switch to liquid engine to go suborbital, and that implies a heck of a lot more mass (tankage, cryo, pumps, much more complex engine, etc...) I don't mean to belittle the monumental achievements of Scaled Composites' with this project, however IMHO the real advances they have made are programatic... being able to accomplish this on a shoe-string budget, with few leaks, not to mention cutting through the beurocratic red tape necessary to DEFINE THE PROCESS of granting a civilian permit for space flight.
BTW, I just ran the calculations, and agree with you on the microsat point. Figuring a 10kg payload, and about 20kg for engine and tankage (pretty optimistic) requires about 160 kg of propellant to get to Vcirc at 100 km. I think a 200 kg 'payload stage' would be quite reasonable.
"It takes considerable knowledge just to realize the extent of your own ignorance." - Thomas Sowell
These go pretty much straight up and back down. Probably don't need to go much over 5-10 times the speed of sound at most on the way up, and much less coming down, since they are made of composites. Orbital requires going real fast (17,000 mph) much closer to horizontal. The de-orbit is where the heat comes in. Unless you carry enough fuel up to slow down entirely by rocket power, you have to scrub that speed by friction with the astmosphere. Maybe real careful and slow and cautious aero braking would do it, but I doubt that's their game, and certainly not with anything based on SpaceShip One.
However, the tourist angle (#1) might be reasonable. But who knows how much rich folk will pay for a few minutes of weightlessness and an astronaut badge?
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are any of the teams contemplating using a helium balloon as the "first stage" of a launch? Or is this allowed? Starting at 50-60 thou feet or above before it lights might be a nice edge....
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Yup, the Da Vinci Project is. They are also supposedly good to go within a year. But no launch date has been set yet. And since they launch from Canada, I guess they don't need any license from the USA?
http://www.davinciproject.com/beta/Technical/Te
A lot of the aviation 'firsts' had nothing to do with commercial interests on the part of the participants. They just wanted to DO it, because they thought they could.
Uh huh.
While I won't argue that Lindbergh was interested in doing this, the $25,000 Raymond Orteig Prize was most certainly a driving force behind the actual attempt. Even the most noble person needs to eat, and unlike science, engineering advances almost always come with some reward, be it financial or strategic.
The Shuttle SRB's, the only man-rated solid rocket ever made, is indeed a rocket that once fired must get fully used, and ejected if you need to quit using it.
Another benefit of using liquid fuels is that you can throttle (I.E. change the flow rate) of the rocket engine as it is fired.
Think about it this way: When you are firing a rocket you are also throwing away mass (Newton's F=ma equation). At the same time, when you are using a typical rocket engine, the actual amount of energy being send out the nozzle stays roughly constant throughout the burn, assuming that you can't throttle the rocket. This means, working the equation backward, force stays constant, but the accelleration rises as the mass drops.
Rockets like this are just fine for a nuclear warhead or for a solid well-built military satellite, but toward the end of the burn you can hit 20 G's or more. Even the Saturn V had this problem to some extent (the Apollo astronauts sometimes hit as high as 8 G's of accelation for brief moments). The Shuttle main engine has adjustable engines that fire at about 105% thrust rating on the launch pad and dropping to about 80% of the rating as it starts gaining altitude... in part to make the ride easier on the passengers.
While there are other issues to follow through, this is something else to consider, and why especially with manned rocket they are almost always liquid rockets.
In addition, the specific impulse (the amount of energy release by a pound of rocket fuel) is sometimes higher with liquid fuels. This is mainly a matter of chemestry, but several factors go into it. I'm sure, however, that some solid propellants have a higher specific impulse than LH2/LOX (the fuel typically used by NASA on the upper stages of most of the manned rockets... this is what caused the falling chunk of ice/foam that destroyed Columbia).
Well as you obviously haven't noticed I thought I'd point out that us brits have a good contender in Steve Bennet who founded starchaser industries they've had lots of succesful launches and I would say they are a lot further along than Carmack though perhaps not quite as far as Rutan. Check it out www.starchaser.co.uk I believe they are scheduled to make an x-prize attempt this year.