US Air Force

The US Air Force's secret spaceplane X-37B OTV-2 has finally returned to Earth, after spending a record-setting 15 months in orbit.

These X-37B orbital test vehicles are Boeing-built unmanned planes that are about a fourth the size of a Nasa space shuttle. They've got solar panels, automatic guidance and nifty thermal silica ceramic thermal protection tiles so it can shrug off the heat of atmospheric reentry.

The Air Force says that the vehicles have been going into orbit "to conduct on-orbit experiments, primarily checkout of the vehicle itself." We also know that there's a super-secret payload on board -- a detail that has fuelled much speculation and rumour.

The first Orbital Test Vehicle (OTV-1) flew from April to December 2010. For its successor, the Air Force wanted to go for even longer.

"We knew from post-flight assessments from the first mission that OTV-1 could have stayed in orbit longer," explains programme manager Lt. Col. Tom McIntyre. "So one of the goals of this mission was to see how much farther we could push the on-orbit duration."

OTV-2 smashed its mission duration of 270 days, and stayed in orbit for 469 days before finally touching down at Vandenberg Air Force Base in California on 16 June.

The Air Force says that the craft "allows space technology experts to continue sending up experiments" -- after the retirement of the shuttle fleet -- "with results returning safely to Earth for study". Defence analysts say that the mystery plane could be used for reconnaissance in conflict regions.


  1. If I were a betting man I would say that this is a precursor for a manned space flight to Mars. A mars mission would take 7 months to get to Mars, Obviously a long time to be in space such things as muscle mass and physiological factors must be taken into account.  

    Jun 19th 2012
    1. In reply to Jason

      "a precursor for a manned space flight to Mars"?Unlikely, for these reasons:1. What does the Air Force want with Mars?2. This is an unmanned space plane.3. This vehicle can reach low earth orbit. Mars is (on average) more than 200 000 times farther away. That is the difference between a 5 minute walk and hiking around the world... 10 times in a row.4. This vehicle was protected from solar radiation by the Earth's magnetic field the whole time.5. Sure, I'll take that bet!  

      Jun 21st 2012
      1. In reply to Andreas

        As Robert Heinlein observed, low Earth orbit is halfway to anywhere in the Solar System. Consider the Saturn V, for example, in which two and a half stages were needed to get to Earth orbit, but only one and a half stages (much smaller stages, too) were needed to get from Earth orbit to lunar orbit and back.If you can get to orbit and stay there for a few years, you've proved almost the whole system for a Mars orbit mission. Landing on Mars and getting back to Mars orbit would require another system, however; for that, something like the Delta Clipper/DC-X or Blue Origin's New Shepard is what's needed.Nevertheless, your other reasons were valid, and I agree that developing technology for a Mars mission is not an objective for the X-37B.  

        Peter G.
        Jul 2nd 2012
    2. In reply to Jason

      are you seirious????!!!!! it has been in orbit for 6 months and.... its RUSTY? mars would literaly disolve it  

      Jul 30th 2012
  2. In what way is this "secret"? The story is actually illustrated with a picture credited to the US Air Force!

    The conspiracy theories make little sense. If this was some kind of surveillance that generated so much data it could not be telemetered back to earth from orbit, surely they would be flying very short missions to get the data back as fast as possible? If the data can be telemetered, where is the USP of this craft over an ordinary satellite?

    The only mission that makes sense is just what they are claiming: testing materials and equipment under lone-term exposure to the space environment. The USP is that the test pieces are gently returned to earth for examination.

    I am very glad space planes are still being developed: they are the only civilised approach to ferrying astronauts to and from space. By all means use unmanned heavy-lift rockets to loft heavy equipment (such as interplanetary spaceships) and then assemble them, with their astronauts, in low earth orbit. Astronauts ought to be able to return under control without getting their feet wet!

    John Hind
    Jun 26th 2012
  3. AS planned Shuttle mark 2.  

    Jun 29th 2012
  4. Planned successor to Dynasoar and XB40 project continues...

    What have they got that they are not showing..  

    Jul 2nd 2012
  5. I would be willing to bet that the prime military objective here is to get weapons into space. I doubt if that's what was on this or previous flights, but it's not much of a leap from payloads consisting of highly sensitive equipment to payloads of highly advanced weapons systems. I would also guess it's primarily focused on providing anti-missile defence (most likely using high-powered lasers) but that's just a guess.

    Last time I checked, the air force were not in the business of funding scientific research except that which they expect to contribute to America's military capabilities.  

    Jul 3rd 2012
    1. In reply to zak

      Yeah, but there are serious conventions barring weapons in space. It'd be analogous to developing biological weapons -- long on illegality and short on new options above our present (legal) nuclear deterrent. I imagine it's more to do with either a) missile defense, and/or b) having the capability to move and defend and rapidly replace our military GPS-analogues -- with the second option making a bit more sense to me.I mean, it wouldn't take much for an asian/pacific power to give us no end of headache by knocking our satellites out of the sky. I imagine it gets harder when our "satellites" are actually mobile spaceplanes and their number and position can vary at will. They can also play "zone" style basketball up there. Knock a couple of them out -- and the net spreads out a bit to cover.  

      Jul 30th 2012
      1. In reply to 3000

        A small fleet of LEO spy drones sounds like something any millitary intelligence service in the world could really use.  

        Juan José Torres
        Aug 14th 2012
    2. In reply to zak

      Any kind of weapon would be loads heavier than scientific equipment, so it would not really be economical when there are already missiles that can reach Earth orbit. However the USSR did put armed space stations up in the 70s, Salyut 3 had a 23 mm Nudelman aircraft cannon.  

      Aug 5th 2012
  6. how about some sort of laser weapon?  

    Jul 6th 2012
  7. you say its The US Air Force's secret spaceplane X-37B OTV-2 secret its not that secret any-more every tom dick and harry knows about it know lol  

    Jul 9th 2012
  8. "As Robert Heinlein observed, low Earth orbit is halfway to anywhere in the Solar System. "
    Apparently, that Robert Heinlein has never opened a book on astronomy. They still cant get people through the Van Halen belt to start with. For some reason, with much more advanced technology, they havent been able to go back to the moon.  

    Jul 27th 2012
  9. The Van Halen Belt? Most Outstanding Ted!  

    Jul 27th 2012
  10. Agree with Zak - Air Force's main mission is force, in the air. Anyway, it's not secret anymore because it's time to allow it to not be a secret. Watch the movie "Moon". A very interesting, little flick. Came out about 4 years ago. There is obviously a lot more going on out of these lesser known launch sites than we'll ever be told.  

    Ad Astra
    Jul 27th 2012
  11. I just love Ted's 'Van Halen belt'. Priceless !  

    Jul 29th 2012
  12. Surely they should fix the ozone instead of destroying it more or there will be no one to send to space and more reason for the need to find a new home  

    Wayne A. Logan
    Aug 3rd 2012
  13. I'm guessing most of you guys are American? You may not be aware of a British project in the '80s called 'HOTOL'. The concept was an upper atmosphere, supersonic aircraft / spacecraft that could either deliver payloads, or, in one form carry passengers from, say, the UK to Australia in a couple of hours. The idea was that the air/spacecraft would launch from a trolley, fly through the upper atmosphere and then glide to earth and land on its own landing gear. This OTV-2, looks very much like HOTOL. Glad to say all the thinking didn't go to waste.  

    Aug 6th 2012
    1. In reply to JB

      Just what I was going to say!  

      Aug 7th 2012
  14. A precursor to a Mars mission was an interesting read.. but only if the AF are planning on installing some sort of interplanetar defence system (which would be quite cool). Nevertheless - along with other commenters here - I think that this is as the AF say, a vehicle purely designed for testing and carrying out experiments at LEO.  

    Aug 7th 2012
  15. Why oh why cannot these people name something in a simple fashion.
    Time after time they show off using daft numbers, letters, dashes etc.
    Why not call it the Space or the Galaxy or the Atmosphere or somesuch.
    How shallow do you need to be to call it the...X - 37B (gap) OTV - 2  

    Aug 7th 2012
    1. In reply to Neil

      Not really shallow Neil, there is logic to the naming.X designates experimental-37 designates the 37th generation of experimental "types" of air vehicleB designates version B of this vehicleOTV is short for Orbital Test Vehicle (good idea to shorten it really yes?)-2 meaning version 2 of this designSimples ;-)  

      Aug 20th 2012

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