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SpaceshipOne's Control Problem Fixed
Baldrson writes "Wired News reports that Rutan's team says they have gotten to the bottom of the June 21 flight anomalies that affected the first SpaceShipOne sub-orbital flight: 1) A control surface actuator had run against a stop limiting its movement, and 2) Wind shear caused the 90-degree roll shortly after rocket ignition. Rutan also said with the problems now identified, the next time SpaceShipOne flies, it will be to win the prize."
It's doubtful that they could get their big vehicle together and working by the end of the year. John has said if Rutan fails they might make a push (ie, work on it more than the current 2 days a week and evenings) to get done by the end of the year for an attempt.
According to John there is no other team even close, and I believe him.
The trip they made on the 21st of June did not count at all for the X-Prize. It did go past 100 km, but it did not have the additional weight necessary to simulate two passengers. Basically it was just another test flight. What was significant about it in a historical perspective is that this is the first time a privately owned company has put a man in space. Thus, they yet to even do the first of two flights required by the X-Prize.
That could mean that it whacked into the stop pretty hard, and then couldn't return. They're not saying which direction the movement was limited in. :)
No he wasn't travelling near his top speed. In fact it was just at the start of the climb.
So I would tend to believe the wind shear explanation:
At the start of the climb, the "plane" (more like a winged rocket, really) had high thrust but low speed, went vertical and hit wind shear. Each wing was going through a different wing mass, and this spun the plane 90 degrees. After that, the plane was going fast enough that wind shear didn't matter.
Incidentally, I was there watching with another 20,000+ people. It was impressive, seeing this white streak shooting vertically.
Serious X-Prize contenders realized early on, there's a lot of rocket technology available 'for sale' out there. They bought rocket engines, and concentrated on the difficult part of the engineering problems, the vehicle to get into space and back.
There's 2 teams that have a chance of actually completeing the X-Prize flights this year. It's interesting, Scaled has used the 'all aerodymanic' approach, with a mothership for first stage lifting to get above troposphere. Da Vinci project is 'all ballistic' with a mothership to provide first stage lift above troposphere.
Scaled is currently the odds on favorite to achive the X-Prize flights first. They have a really good chance, they have all the flight hardware, and it's been thru rigorous testing. Still, manned space flight is HARD (just check with Nasa for reference), and it's NOT a given that the SS1 + WK combination can complete 2 more flights without incident. A serious incident with either vehicle, and Scaled will be out of the running for the X-Prize, there isn't time left to replace either of them.
Da Vinci project has flight tested engines, but, they have yet to flight test an all up final configuration. They have the permits in place, and, the hardware is built. They are expected to start flight testing within the next 6 weeks.
Armadillo, well, they are tinkering with rockets, and writing a blog about it. They dont have a vehicle to mount an all up configuation rocket in, and they dont have a design to build one from. The X-Prize must be claimed this year, and Armadillo hasn't even got a vehicle design yet. No, they are not in the running, and have no hope of being in the running. If you haven't done the engineering analysis on a design, to validate it should be capable of withstanding the launch/recovery portions of the flight, and got the hardware built, ready to fly this summer, you are not in the running for the X-Prize. No matter how much money you throw at it, you are not going to design/build that package in the next 4 months, and if it's not flight ready in 4 months, you cant meet the requirements for winning the X-Prize.
Nobody considers Armadillo anywhere near close. The other team that's close is Da Vinci project. They are the only other team that's actually got hardware constructed with any amount of testing (photos) done on it. Thier schedule calls for the first sub-orbital test flights in august of this year, and they are the only X-Prize team other than scaled actually planning to fly this summer. they are also the only other team that has minor details like launch permits etc all wrapped up.
Cancer and aids research is ongoing. It hasn't stopped. But it's a tough nut to crack, obviously. Also, realize that if a cure for cancer is ever found, governments and private citizens around the world are going to scream that the drug should be given away for free. Some may threaten to allow their country's companies to reverse-engineer the drug and sell it cheaper if the inventor's don't play along. If the successful inventor stands their ground (as they'll be ordered to do by shareholders - remember this is likely a public FOR PROFIT company), there will be expose's on 20/20 about the evil corporate drug giants who hold life in their hands and won't dole it out...
It's a no-win situation. Dump millions into cancer research only to be called evil for attempting a return on investment. Or don't spend millions on cancer research and be called evil for not doing it.
Believe it or not, drugs like Viagra provide a valuable benefit to men who've survived prostate cancer. Figure it out if you like, but the fact is that Viagra is a life-enhancing drug for a lot of people. Is making life for large numbers a bit better that much less meaningful than curing cancer for a relatively smaller number of people?
I personally believe that the commercialization of space flight is a good thing. Part of why NASA's long range probes have been so successful (and cost effective) in recent years has been the use of COTS (Commercial Off The Shelf) parts. Much easier to do than developing everything in-house. Imagine if you were able to buy the pieces to build a viable space vehicle - NASA's costs should come down, and the amount of space exploration should increase.
Plus, there are likely scientific advancements that will come about simply because of cheapening space travel. I know that the semiconductor industry will probably get a boost if it gets cheap enough to do large-scale MBE (Molecular Beam Epitaxy) in space - right now it's really inefficient on earth due to the vacuum equipment needed to pull it off.
Actually, you are doing Pfizer somewhat of a disservice here. They were actually looking into drugs to be used during heart surgery, specifically drugs to be used to lower blood pressure during same.
During some trials an interesting side effect was noticed. I expect there were some happy happy people.
FYI & FWIW For those interested, high blood pressure is often a cause of impotence (though many might incorrectly argue that a higher pressure might be useful!). Of course, stress causes high blood pressure, and not being able to get (or retain) an erection causes stress! My but men are just a big mixed up bag of emotions!
The problem is that the muscles that restrict blood flow out of the penis are overwhelmed by the excessive blood pressure, and the erection subsides, or is never present. Along comes this wonder-drug for lowering blood pressure during heart surgery, and, as a side effect, it also lowers the pressure so that those handy muscles can retain the blood in the penis and hence keep (or allow) an erection.
Eclectic beats from Leeds, UK
handmadehands.co.uk
This is utter BS.
NASA was started to consolidate flight research centers. They were scattered in several agencies, although the NCA, widely considered the predecessor to NASA, did operate many of them. With the importation of V-2 rockets from Germany (with a little help from the U.S. Amry going in and taking the rockets by force) rocket research really started to get into high gear. This is where the term "rocket scientist" really came into its own, because before that a rocket scientist was a crazy lunatic like Goddard or Oberth who loved to blow things up.
Both the U.S. Navy and the U.S. Army got into a competition (not with Russia, but with each other) trying to see who could develop these rockets first and claim supremacy on their use. This was no different than what these two military branches did with aircraft just a mere 20 years earlier, including several officers who were involved with the early testing of military aircraft. Both the Navy and the Army Air Corp (later reorganized as the U.S. Air Force) launched thousands of rockets, learning quite a bit regarding how to build them, how to handle them, and what they really could be used for (in addition to putting a nuke on the top of them... that was obvious even to Hitler during WWII).
Later on, particularly after Sputnik achieved orbit, the Eisenhower Administration looked around and saw three competing space programs in the U.S. government. That was the Army, Navy, and a very anemic NCA which was a civilian program. What happened was a transfer of many of the people involved with the Army and Navy programs to the NCA, which was then renamed to become NASA. The parallels with what happened after 9/11 to form the TSA and the Dept. of Homeland Security can compared to how NASA was formed, and this is almost typical knee jerk reaction by Congress.
Because most of the working rocketry projects were already military, NASA took on a military flavor. And of course since many NASA personnel still had connections to the military, those people involved still tried to push goals that would benefit their respective armed services for weapons research. It paid off with the missile programs that are still maintained by the Air Force and Navy, which I guess was your "thinly veiled military control of the program".
NASA was concieved as a civilian-run agency from the beginning because it was obvious to everybody involved that spaceflight would take on aspects that were clearly non-military as well. In addition to trying to sell the program to the American people by trying to give ordinary citizens a "stake" in the program, there was an implied concept that commercial interests would also get involved. AT&T built one of the first commercial satellites (Telestar) and even paid for the whole thing out of their own pocket, including the rocket construction and the salaries of most of the ground crew (by contract through NASA) to get the thing up into space. What happened to kill the Telestar program should speak volumes for what was to come from NASA and is still an issue today.
The big push to seriously expand NASA occured during the Kennedy administration, where JFK was litterally reading some science fiction books, and got a sort of stary-eyed vision about where NASA could go. It was entirely his idea to get astronauts to the moon, and to push for NASA to become even more under civilian control. This was when the second batch of astronauts was announced, and included for the first time civilians like Neil Armstrong who did not hold military rank.
Regarding Columbia: You are doing a huge disservice to the memory of those astronauts to even repeat a wild rumor that has no basis in fact. While there are many things I can complain about regarding how NASA dealt with Columbia, it was not an intentional and deliberate action to kill astronauts. If that were the case, there would be no astronaut corp left at NASA, and they more than anybody else would know more about those issues than any tin-hat conspiracy
A few months ago, I took a class on Pilot-Induced Oscillations (PIOs). As an aerospace engineer who works on military high performance aircraft, I know how bad PIOs can be, and just how deadly a problem they can be. This looks like a classic PIO, triggered by a control problem.
To summarize the two-day class into one paragraph, a PIO is an oscillation that is generally sustained by pilot inputs, is usually triggered by some external event, and has at least two common causes: rate-limited control actuators, or so-called "phase lags" (lag between input and output).
Relevant to this case, then, is the roll actuator (the hydraulic device responsible for moving the roll control surfaces). It sounds from the non-technical answer in the article "the actuator delayed moving one of the ship's flaps" like a rate-limited actuator. The pilot demanded a larger input faster than the system was able to provide, so the control surface hit its stop.
What ends up happening, in such a case, is that the pilot doesn't get the overall response he expects, so he puts in MORE input. But then it turns out to be too much, so he puts in a response the other way - but it takes a while to start reacting, so he puts in MORE input... etc. etc. etc..
Also, the "external event" in this case was probably a wind shear. You can have a PIO-prone system and it will fly just fine - right up until you hit that trigger event which is just large enough to throw you into a PIO - and then you're basically hosed. Nothing you can physically do will stop the PIO - OTHER than just releasing the controls and letting everything stop naturally - because it's the inputs that drive the oscillation. And you can bet that's quite frightening for a control-freak pilot who's afraid he's about to lose control. Takes a LOT of training in how to recognize it for what it is; stopping it is easy (if you have time or altitude) - just let go.
To fix a control system that has PIO problems, you can (a) increase the authority of the control device, (b) increase the response speed of the device, or (c) decrease the phase lag so it responds more quickly. None of those fixes are trivial, unless they're caused by a broken component.
I'm quite sure Rutan, of all people, is intimately familiar with this issue, and I have no doubt that he and his team will address it appropriately.
--Brandon / Split Infinity Music
The kind of turbulence of which you speak can have very drastic affects on an airframe. Particularly if the turbulence is generated by something heavy flying slowly and you are in something light. They will teach you in class to stay above and well behind anything heavy and slow in front of you. Note that slow for them may be in excess of your maximum attainable speed in level flight!
In other words, its certainly a real issue, but any turbulence encountered by SS1 was not due to turbulence from other craft.
There's also the Canadian Arrow that starts test flights next month. As a Canadian myself, I'm very happy that both Canadian teams are poised to actually make attempts by the end of the year. O Canada!
Save the whales... Collect the whole set.
No, they're using a peroxide/methanol mixture as the fuel. I think Carmack mentioned exploring ethanol instead of methanol in a post at the xprize.org message boards. And of course, recent updates also indicate that they're exploring liquid catalyst, with disappointing results to date.
I believe the issue of energy loss due to the use of vanes was also addressed (though perhaps not to your satisfaction) in the Armadillo thread at xprize.org.
Armadillo was using high purity non-stabilized peroxide up until roughly a year ago. It does not need injected liquid catalysts: just using silver and platinum, or various other solid catalysts, works just fine.
Now, Armadillo is using a mixture of 50% unstabilized peroxide and methanol. It has about the same energy per unit mass/volume as 90% peroxide does, but is a fraction of the cost and handling issues of 90% plus unstabilized peroxide. Still a monopropellant, but very much simpler and cheaper.
Please read harder. Armadillo has been describing their rocket motors in detail repeatedly.
Isp is not everything. For a first stage, density impulse is much more important. And for a non orbital rocket vehicle, handling and ease of design and construction are also very important.
Amateurs talk Isp; Professionals start with density impulse and then system design tradeoffs on the overall vehicle; Experts talk development cost and timeline to get vehicles that meet the minimum requirements flying successfully.
Not NO3. N2O; Nitrous Oxide.
Why? It's not a bad oxidizer, that's why. It has less oxygen than LOX or peroxide or nitrogen tetroxide or nitric acid, true. But like peroxide and hydrazine, it's got internal energy, so when it starts to react the dissassociation adds energy to the reactions. That evens it out. Nitrous is decent overall performance and self pressurizing, which none of the other oxidizers are.
Again: Specific Impulse is not everything. It's a lot simpler, safer, easier to develop a vanes system than a fully gimballing motor. Less mass is moving, no propellant lines are moving.
Real rocket innovators have been looking at jet vanes on and off continuously for the last decade. Most chose to go another direction, but they are not a bad choice for certain sets of vehicle design and development assumptions. Carmack's group called that one right: it is a good choice for their vehicle and their development program.
Well, fine, but at the very least you could read up on the actual details and see what other people who actually know something about rocket design think about it.
I would never have developed exactly their vehicle, however, Armadillo are making incremental good choices and have a clue about both ultimate performance and doing development on
The X-Prize Foundation originally tried to raise all fo the funding to make the prize essentially open-ended. They got to about $5 million before they hit close to a brick wall in raising much more money other than nickle and dimes that the occasional space enthuisist was sending forward. That was when they "bought" an insurance police to get the rest of the money, on the condition that it had to be won by the end of 2004.
This is why there is a time limit. It wasn't there originally, but once there were several teams making some serious progress toward the goal, they decided to make the prize fully-funded if it were to be won. It also put a little bit of time pressure on some of the teams, who had earlier been trying to refine their vehicles rather than really pushing for the deadline.