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Robotic Space Plane Launches In Mystery Mission This Week
mpicpp writes: The United States Air Force's robotic X-37B space plane will carry a NASA experiment into orbit when it launches on its next mystery mission Wednesday. The liftoff will begin the reusable space plane's fourth mission, which is known as OTV-4 (short for Orbital Test Vehicle-4). Since it's classified it's not entirely clear what the space plane will be doing once it leaves Earth Wednesday. This has led to some speculation that the vehicle might be a weapon, but officials have repeatedly refuted that notion, saying X-37B flights simply test a variety of new technologies. The X-37B looks like a miniature version of NASA's now-retired space shuttle. The robotic, solar-powered space plane is about 29 feet long by 9.5 feet tall (8.8 by 2.9 meters), with a wingspan of 15 feet (4.6 meters) and a payload bay the size of a pickup-truck bed. Like the space shuttle, the X-37B launches vertically and lands horizontally, on a runway.
The Air Force has weaponized systemd and is launching satellites that can download it onto enemy computers at a moments' notice.
I hate to feed the trolls, but:
1) This is US Military, not NASA
2) The NASA budget is $18.4 billion or about 0.5% of budget
3) Dividing $18B amongst the population of 319M will give everyone $56. Not a good basic income.
4) NASA does some really great stuff that benefits every american citizen immensely. Like your 10 day weather forecasts? LIke your GPS navigation. Thank NASA.
5) There is nothing wrong with a good test platform. Where else are you going to get long endurance recoverable space data for classified purposes? Not the international space station to be sure.
Space weapons aren't illegal. You just can't have orbital weapon platforms for weapons of mass destruction (think nukes).
It's perfectly legal for any country to send up a satellite that could attack other satellites or space stations. It's even fine to put one up there that uses conventional warheads or kinetic weapons against targets on earth.
It's also perfectly legal to put up weapon platforms that are capable of launching nukes from space - it's just not legal to arm them with actual warheads.
The reason we don't do much of any of that is because a) we have no reason to attack anyone in space (yet), b) we can shoot down satellites from earth just fine, and c) we can attack other places on earth more efficiently and with less cost without orbital platforms.
Those who can't do, teach. Those who can't teach either, do tech support.
4) NASA does some really great stuff that benefits every american citizen immensely. Like your 10 day weather forecasts? LIke your GPS navigation. Thank NASA.
NASA does do some really great stuff that benefits every american citizen immensely, but your examples are horrible.
Weather forecasts are handled by National Oceanic and Atmospheric Administration (NOAA - I love that acronym for a weather agency!), who operate their own birds (though a few were launched by NASA).
GPS is built, launched, and operated by the U.S. Air Force. NASA has literally nothing to do with GPS.
Maybe because NASA is a political football that isn't allowed to do really cutting edge stuff without subcontracting the work to 48 out of 50 states to secure funding from Congress, while secret military programs can do science with less bother. Some of the Area 51 programs involved in developing OXCART ended up ahead of schedule and under budget because keeping stuff confidential sheltered it from the usual MIC/appropriations morasd. Likewise SpaceX is now on the cutting edge of rocket recoverability because it's more capable of taking risks and less hamstrung by accounting oversight. Maybe covert projects like the X37b are simply easier organizationally and thus easier avenues to doing unconventional science like testing ion engines than is the civilian space program. Remember, Hubble became possible because of Keyhole, which worked out the materials science and engineering aspects in secret.
Okay, I know it's probably the least important thing about the craft, but still...
Why are they using such an ancient, decrepit-ass rocket motor? The AR2-3 is incredibly old - it dates back to a Gemini-era trainer, basically a modded F-104 that NASA used for early tests and training for spaceflight. It was made back when rocket chemistry was still in the "even the experts don't know much" stage, so it burned jet fuel and high-test peroxide (90%+ H2O2 in H2O).
Jet fuel is not good for rockets - basically, the restrictions on what compounds can be present is fine for jet engines, but leads to horrible problems with rockets. There's a specific petroleum-product blend designed for rockets, called RP-1, which clamps down on things like sulfur compounds or alkenes that love to gum up the works. This rocket was originally used on a jet fighter and shared fuel with it, so that was understandable... but the USAF recertified the engine for modern JP-8 instead of the old JP-4. So they already went through the effort of making it work with a new but similar fuel. Unless the X-37 hides a jet engine on itself somewhere, I don't see why they couldn't have used RP-1 instead.
Further, rocket science moved away from peroxide for a reason - it's dangerous. It will explode for basically any reason - peroxide decomposes exothermically, so once it starts reverting to H2O + O2, it's nearly impossible to stop. And it reacts with tankage surprisingly often. Oh, and it does horrible things to your specific impulse, which really hurts you on a last-stage engine like this one.
Honestly, using the engine at all is a weird choice. Sure, maybe they had some laying around... from the sixties... but that's like putting an F-104 engine in a prototype aircraft, it just doesn't seem right when other off-the-shelf systems work better. An AJ-10 would have worked beautifully. An RL10 might not have fit the aero package (hydrogen is a bulky fuel), but would have given them some impressive dV if they wanted it. Aestus would be a perfect match as well, if they didn't mind outsourcing to the Euros. Even Kestrel would work (although it first flew around the same time as this, so understandable not to use it). Point is, they had options, and being the Air Force, they could easily have just had an engine custom-made for it if they so wanted.
So what are the implications? All I can think of is a) they don't care how badly the rocket performs, b) they probably aren't going to keep that engine in whatever "production" version they build, or c) they have some other reason to use peroxide or JP8. Maybe peroxide is also their monoprop for RCS? That isn't really worth it though, particularly when UDMH works better as RCS and in the main motor.
Weather forecasts are handled by National Oceanic and Atmospheric Administration (NOAA - I love that acronym for a weather agency!), who operate their own birds (though a few were launched by NASA).
NASA provides the design, launch, and project management for the NOAA satellites up until they are in orbit at which point the operations is turned over to NOAA. The last system they tried to launch with a reduced role for NASA was NPOESS--which was a complete failure. (Not all of which was NOAA's fault, it was a horrible idea that tried to merge NOAA & DOD requirements, but the reality is that there was no more appetite for NOAA to try to take on tasks that were being handled well by NASA and the successor project, JPSS, returned to the historic model of NASA program management driven by NOAA requirements.)
NASA had nothing to do with the microwave oven. Diathermy (therapeatic heating of human tissue by radio waves) was being used in 1930. Westinghouse demonstrated cooking food using short waves in the 1933 Worlds Fair. The cavity magnetron was perfected early in WW2. Percy Spencer noticed a candy bar in his pocket melting when he was working close to an operating radar in 1945. He experimented with heating food in a metal box fed from a magnetron the same year; Raytheon filing a patent for it. Raytheon built he first "Radarange" in 1947. A public vending machine was producing hot dogs in Grand Central Terminal in 1947.
Are you sure that would be the reaction? I don't believe that to be the case, after all Russia and China have both had military test platforms in space. Russia even weaponized at least one of their space stations.
APK likes to ask for responses to the same things over and over. Maybe he just likes the responses?
In case you haven't looked at the pictures: Take a look. So, is it true that the internals are lopsided so that that one engine actually is thrusting colinear with the center of mass, like you seem to assume? Nope! If the internals were lopsided then the wings would need to be asymmetric or it would suffer some pretty serious torque when gliding. The reason the engine is offset is that the origional design called for two engines. This was overkill for the amount of thrust required, so they cut one out. It would have taken some redesign to have the single engine back in the center, and since it gimbles far enough that it can still produce a thrust vector colinear with the center of mass, there was no reason to do so.
So to answer the actual question "It works by turning the engine a little bit to compensate".
ASCII stupid question, get a stupid ANSI