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SpaceShipOne Flight Not as Perfect as it Seemed
ArbiterOne writes "SpaceShipOne's flight wasn't as perfect as it seemed, according to Burt Rutan and New Scientist. Apparently, at one point in the descent, the pilot completely lost attitude control. According to him, "If that had happened earlier, I would never have made it and you all would be looking sad right now." Could this pose some problems for the X-Prize contender?"
RTFA - this is covered.
Who said it was perfect in the first place? Every news story I read talked about the problems they had. Where were you guys?
Attitudeis the crafts orientation. The article originally said altitude control, I emailed CmdrTaco to fix it before the article went live.
"Prefiero morir de pie que vivir siempre arrodillado!"
Is this a mistake or do pilots really have control over their attitude?
Uh... I would hope they have control over the plane's attitude.
Main Entry: at-ti-tude
5 : the position of an aircraft or spacecraft determined by the relationship between its axes and a reference datum (as the horizon or a particular star)
"The position in space of a spacecraft or aircraft. A satellite's attitude can be measured by the angle the satellite makes with the object it is orbiting, usually the Earth. Attitude determines the direction a satellite's instruments face. The attitude of a satellite must be constantly maintained; this is known as attitude control."
You're welcome.
Hmmm.
No, it is attitude
Attitude is an aeronautical term for orientation as well as a term for someone's emotional state, so you can stop with all the typo jokes now. It IS possible for lack of attitude control to affect the pilot's attitude. Something like going from "This is fun" to "HolyfskingShit!" Deadweight - Commercial Pilot
So, huh...
Maybe he and his boss Rutan are concerned about the public getting excited about jumping into a tin can which only through sheer coincidence did not kill the test pilot?
This announcement means as much to me as the flight itself, and paradoxically lends support to those comments in the voting area about Scaled Composites being trustworthy enough to warrant flying their craft.
You misunderstood, the XPrize is a contest for civilians.
going around the world on a raft is a contest for amateurs, going into space is a job for Hobbyists, which aren't necessarily doing it for free, only for fun. ANd Paul allen is by definition is an ameteur since he's never funded space exploration before.
Food not Bombs is a nice platitude but it breaks down when you notice that the Bombees are usually well fed
SpaceShipOne does indeed have cold gas attitude thrusters. You can see a photo of one firing during a test flight here.
In Soviet Rush, today's Tom Sawyer gets high on you.
Perhaps Taco should read check his submissions a little more closely before approving them: Melvill lost attitude control "end of the rocket engine's firing time of about 70 seconds, just as Melvill reached space". That would be in the ascent phase.
Attitude of an aircraft: The relationship of longitudinal axis (fuselage) and lateral axis (wings) to the earth's surface or any plane parallel to the earth's surface.
I would still suit up and hop in if asked. Granted, I have zero experience flying (although I did stay at a Holiday Inn Express last night!), but I would still do it. The view alone would be enough to make me happy before I die. These guys knew what they were doing, and that minor things do go wrong. Minor things can be catastrophic things at 3.2G, though. We are all glad that the pilot was unhurt.
I hate sigs.
Once you are in space your inertia will carry you along what ever path you started. So if you start in the proper attitude, and under control, you'll return to the atmosphere in much the same condition. If you leave the atmosphere tumbling out of control, you'll hit it out of control and you'll be far less likely to ever regain it. Indeed, at that air speed, as you drop you into thicker air out of control you are far more likely to suffer complete structural failure. That's bad.
If brevity is the soul of wit, then how does one explain Twitter?
The loss of attitude control was during the ascent, not the descent. Mike lost control of attitude right before SpaceShipOne popped out of the upper atmosphere. Because there was no air, he was able to more easily regain control as the loss of attitude had no more effect.
Obligatory Simpsons quote:
I for one welcome our new M&M overlords!
Bitten Apples are still better than dirty Windows...
Any landing you can walk away from is a good one!
quiquid id est, timeo puellas et oscula dantes.
And yes, Chuck Yeager (IMHO) was the greatest. The book reminds us of the distinction between real pilots and astronauts (mostly passengers). The guy who piloted Richard Noble's Thrust (supersonic on land) and the guy who piloted the Rutan craft are pilots.
Panurge has posted for the last time. Thanks for the positive moderations.
FL 600 is a bit high, but not so much as seems to be implied here. No a current Lear can't make 600 (at least I don't think they can - didn't bother to look it up), but it isn't that awfully ludicrous.
You don't perhaps think that FL 600 means 600,000 feet (or meters, or whatever), do you? It is 60,000 feet.
wrong.
Most objects do not spin cleanly about most axes. Rigid bodies (such as books, spaceships, rocks, lollipops, and bullets) have three "principal axes" that pass through the center of gravity and are determined by the mass distribution in the object. There's a "minimum" axis that minimizes the kinetic energy for a given angular momentum -- that's the axis around which the thing is the most clustered. For a screwdriver, the minimum axis generally points down the length of the scredriver shaft. There's also a "maximum" axis around which the thing is the most spread out of any direction. For a flat object like a book or a pancake, the maximum axis points directly out of the flat face. Those are the only two axes around which you can spin the object and have it stay stable.
Any other direction will give rise to precession and tumbling, even in vacuum! You can try it with a book -- most closed hardback books have the minimum axis pointing up through the top of the middle pages, and the maximum axis pointing out through the front of the cover. The third dimension -- pointing out through the spine -- is not stable. Tape a book shut and flip it in the air: if you flip it around the maximum or minimum moment axis it will do what you think -- just flip over before you catch it again. If you flip it around the intermediate axis (by, say, starting with the book facing you right-side up with the spine on the left, and pulling the bottom edge toward you as you throw it up in the air) then you might expect the spine to stay on your left side -- but it will flip back and forth, often ending up on your right side, as the book tumbles in the air. (Remember to tape the book closed before tossing it!).
Anyhow, that's a problem for stopping spin and tumbling, because it's not always obvious which way to fire the cold-gas jets to slow down your rotation: by the time you actually fire them you might have tumbled around so that they are speeding you up instead of slowing you down.
I guess that's why "carefree re-entry" is such a great feature of SpaceShipOne -- it's remarkable that they were able to land safely even without good attitude control at apogee.
The flight was convered in greater detail in yesterday's news. While they weren't expecting loss of trim, they did anticipate the possibility, and had a backup system.
There was a show recently on PBS about the Joint Strike Fighter selection competition. The first flights of the aircraft were done with the landing gear down because with all the other uncertainties they didn't want to take the chance that the gear would fail to lower. They had glitches with hydraulic leaks, landing gear brakes, the VTOL systems, and refueling equipment. In any kind of new aircraft, you expect there to be lots of little problems, more than a few of which are capable of killing the test pilots.
Rutan doesn't seem to be taking any unnecessary chances; he's taking this step by step. If he was just rushing break-neck to win, he'd be going for the prize today. We don't know at this point how much of a setback these glitches were, but I'm reasonably sure he has time for dealing with them charted out in the project.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
The history geeks among us will remember that Yeager had the same problem with that modified F-104 used for NASA pilot training. Enough out of the atmosphere for the aerodynamic controls not to work, but not enough into space for the peroxide jets to function either. I hope SS1 recovers from a spin better than an F-104 does.
What if it is just turtles all the way down?
Say what you will about Reagan, regardless of how you felt about his policies (many were quite controversial), he sure could deliver great speeches.
The best lines in it, however, were paraphrased from John Gillespie McGee's famous poem "High Flight", which is also what Melvill was most likely thinking of. It's a standard reading at the funerals of pilots, and I personally feel that Reagan's speech would have been better, and perhaps more fitting, had he finished with the entire poem. It sums up the main reason why astronauts - military, governmental or private - will always want to strap themselves into something that will never be 100% safe and fly.
What's even more amazing is that the cost per flight is amazingly low, they're saying about $80,000.
This is about what it costs to fly a 747 across the country.
thad
I love Mondays. On a Monday, anything is possible.
On the CBC's science show Quirks and Quarks this past weekend, they interviewed the leads of both Canadian teams, and both stated that they were planning to make an attempt in August. Thats 6 to 10 weeks from now, so there may still be a race on if the Rutans can't fix the problem right away.
I'll compare it to normal space flight.a ce_launch_costs.htm)
So, thats actually pretty impresive if you ask me.
The last shuttle, Endeavor, completed in May 1991, cost $2.1 billion and was designed to be used for 100 trips (which divides out to $21 million per trip). This winds up being a rather minor part (7%) of the total cost of a space shuttle launch, estimated to be $300 million per launch for the first eight flights in any given year (through the year 2020). (taken from http://www.distant-star.com/issue13/april_2003_sp
The space station is orbiting at 360 km right now. Does that mean it isn't in LEO either?
...they describe weightlessness as though it's a property of leaving the atmosphere...
He became "weightless" the instant he cut the thrust, because then the only acceleration acting on the aircraft was gravity. I.e., he still had weight, but he was unable to feel it, because he was coasting freely along with it.
Hmm. Well, total program costs back then were $150 million (which is about $843 million in '02 dollars). Scaled Composites looks to have a hell of a bargain on their hands.
SP
"It is dangerous to be right when the government is wrong." - Voltaire
M & M's won't mlet all over the place (assuming the candy shell remains intact). The founder of Mars (parent company of M & M) got the idea when he was in the (Sahara?) desert & saw the locals eating a hard-shelled candy.
There's an old story from Analog (a science-fiction magazine) titled 'Amateurs' which reminds me quite a bit of the guys at Scaled Composites, except in 'Amateurs', they didn't have a government prize to spur them on
You appear to think that the X Prize has been put up by the government.
This is not correct.
The X Prize is completely private. Peter Diamantes has raised several million dollars from private donations. This has then been used to pay the premium on an insurance policy, with the insurance company essentially betting that the X Prize will not be won before the end of this year, and Diamantes (and the competitors) betting that it will be.
The government is not involved in any way other than in getting out of the way (which the FAA is doing a pretty good job of -- a year ago there was no legal way to make a flight such as yesterdays one).
In the previous flights, the nozzle and rocket motor casing was smaller than the one used for Monday's flight. Also, an aerodynamic fairing was added that covered most of the nozzle this time.
How many times do we have to hear this? I've cited this article on Slashdot before, and if necessary I will cite it again. Steven Kelman explained it in Government Excecutive magazine, back in 1998.
Mind you I don't disagree with you on the issue of those school boards getting screwed on wireless networking equipment...the point is that sometimes the accounting is unintentionally misleading, and these sorts of numbers don't necessarily always represent waste or fraud.~Idarubicin
I just released a video of 50 minutes worth of yesterday's CNN coverage into the wild via LimeWire. Load up your Gnutella client of choice and search for CNN-SpaceShipOne.wmv, if it's not 186MB (196,468,036 bytes) then it's not the right thing or incomplete.
Oh, you mean nose-uppy and nose-downy?
Nose-uppy/nose-downy (ptich), wingtip-uppy/wingtip-downy (roll).
But (unless I misunderstand the term and it's specificially excluded) the dictionary missed yaw: Nose-righty/nose-lefty.
An aircraft's position at any instant has six degrees of freedom: Three of attitude (roll, pitch, and yaw), three of location.
Additionally there are the deriviatives of each of those (i.e. position gives three each of velocity, accelleration, jerk, snap, etc., attitude gives roll/pitch/yaw rates, etc.)
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
Interestingly enough, his name isn't 'Bert Rutan'. Thankfully, it's not 'NASA' either. It's 'Burt Rutan'
From here:
They managed a total of 12 launches, with the final (NASA-run) one resulting in destruction of the vehicle due to mistakes made by the ground crew which prevented one of the landing legs from deploying correctly.The "official" blame for killing DC-X was that they couldn't build a composite fiber fuel tank big enough, but the real problem was the $billions that Boeing and Lockheed (or Rockwell, at the time) would have lost in support contracts for the Space Shuttle, which probably weighed heavily on the consciences of some Alabama, Washington and Florida congress critters also.
You are here confusing the X-33 program, which was run by NASA and built by Lockheed, with the DC-X program. DC-X died because NASA didn't like it. The X-33 program was indeed killed partly as a result of their inability to build a "conformal" composite propellant tank, as well as severe cost over-runs and a growing realization that it would never carry any significant payload. However, the X-33 design was significantly different than the DC-X/Delta Clipper design, and in many ways pushed the technological envelope much further (which was a major cause of their later over-runs). Why NASA picked the Lockheed design (which was essentially just some marketing material at that point) over the Delta Clipper (which had flight-tested actual hardware) as the winner of the X-33 contract has always been a mystery to me.
Well, because TECHNICALLY he entered space. He IS an Astronaut.
NASA doesn't award Astronaut status until 50 miles. So it's possible to not enter space, which is defined as 100km(62.1 miles) but still be given the title of Astronaut.
Definitions found here
So what are we going to call these guys, Private Astronauts?
Yes that is very true. But if they want paying passengers, attitude control is one of the worst things to have go on the fritz when you are going very fast. Titan IV rocket back in 1998 had a little attitude control reset around 40 seconds into flight. It pitched over and before it got too far (seconds at most) it fell apart from the forces. Range safety then sent command destruct to try to make big pieces into little pieces. Fortunately the pieces were landing in the ocean. SpaceShipOne probably more forgiving, but it is still a very big concern. Since it came back in one piece, they have the chance to fix the problem. They have to fix it.
Our founding fathers removed the guys in charge. Be American. Vote incumbents out.
The Mercury spacecraft was designed such that it would naturally orient itself properly. (And on the Shepard and Grissom flights it certainly counted as a 'manned exoatmospheric craft'.)
It's wings that make the need for precise control necessary. Rutan avoids this issue to some extent by aereodynamic tricks.
A few nits:
The airspace above FL600 was changed to Class E in 1998. The events of 9/11 had nothing to do with it.
The upper limit of Class E is not "NaN". Class E ends at 100,000m (62 statute miles if you prefer). Above that is "space".
Class E is only controlled airspace where IFR flight is concerned. You don't need an ATC clearance to fly above FL600 if you are operating in accordance with VFR.
Most people assume you can't get to FL600 without passing through Class A. That's only true if you stay within 12 nautical miles of the U.S.A. coastline, as mentioned above. There is some uncontrolled international airspace, or at least there used to be. Of course, you can also get to FL600 via Class F airspace. This would require permission from the agency responsible for that airspace, but wouldn't technically require an IFR clearance.
One might also offer that certain Apollo (1) folks might have not wanted their TEST FLIGHT to go deeply wrong.
Rockets are dangerous. Space flight is dangerous. This isn't a run to the 7-11. So far, NASA and the US have been excessively successful in space flight.