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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.
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.
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