Original URL: https://www.theregister.com/2011/02/04/x37b_ski/

Russia has 'secret space warplane' to match US X-37B

Cold War 'Hurricane' shuttle-interceptor reborn?

By Lewis Page

Posted in Science, 4th February 2011 12:24 GMT

Russia has claimed that it too is working on an unmanned pocket spaceplane similar to the US military's mysterious X-37B roboshuttle, dubbed a "secret space warplane" by the Iranian government.

The X-37B at Vandenberg AFB following maiden flight. Credit: USAF

What has the robot spaceplane collected up there?

Flightglobal reports that Oleg Ostapenko, a senior official of the Russian Space Forces, commented with respect to the X-37B's recent maiden flight that "something has been done [by us] along these lines".

The X-37B is a small, winged, heat-shielded spaceplane which is launched into orbit inside a fairing atop a conventional rocket stack – rather than making use of its own engines and strap-on boosters like the Space Shuttle.

Once in space, the X-37B exhibits another important difference from the Shuttle: it deploys a solar array, allowing it to stay in orbit for long periods. The Shuttle's electrical systems were powered by fuel cells, meaning that it was unsuited for long stays in space (unless perhaps docked to the International Space Station).

The first and so far only flight of the X-37B lasted 224 days, with the little spaceplane coming in to land autonomously on a runway at California's Vandenberg military space base last December.

The US Air Force, owner of the X-37B, suggests publicly that the little spaceplane is intended mainly to allow quicker deployment and testing of new technologies in space. Supposing you had come up with a new sensor, for instance: normally it would have to be made as reliable and likely to work as humanly possible, then built into a satellite of its own with solar panels, protection, power systems, communications and all the rest. Only once this had been launched would you have any idea if the new kit even worked. If it didn't, you'd just have to write off the cost of the satellite. Either way, the process would have taken a long time.

With the X-37B you could build a reasonably good effort at the sensor, plug it into the spaceplane and launch it very quickly. If it didn't work you could bring the X-37B down straight away, and possibly fix the duff payload and send it up again fast. If it wasn't fixable, you'd at least have saved large sums on a satellite and on removing all possible risks from the trial package. And no matter what, you'd have got your new technology into space a lot more quickly than you would using normal technology.

Still though, it is secret. And it has the same wings that the US military insisted on for the Shuttle

In this view, the X-37B is more in the nature of a swappable-payload reusable satellite than a "secret space warplane". But there are other factors which make it – and the suggestion that Russia has such technology too – quite interesting.

First, there's the fact that the X-37B is funded out of the so-called "black" or secret budget and the US Air Force refuses to offer any serious details on its specifications or mission. The only reason anybody knows about it is that before being taken over by the military the project was run and funded by various different US agencies including NASA. So it is "secret", at least.

NASA's original long-endurance X-37 orbiter concept

See? Just a satellite with wings

Second, the X-37B has a powerful orbital manoeuvring engine and a decent size fuel tank – and because it is reusable, its controllers don't need to eke out its fuel for years the way they would with a normal satellite. This means that the little spaceplane is well suited to the making of major orbit changes. This will allow it to appear suddenly over places it isn't expected and to evade location from below for quite long periods – as it did during its maiden flight, in fact.

Third, there's the fact that the X-37B's wings have a strong resemblance to those of the Shuttle. These wings are a good deal bigger and heavier than they need to be merely to achieve a runway landing from orbit: it would have been quite possible to use smaller "stub" wings, or even design the craft as a so-called "lifting body", using no wings at all and gaining lift from the shape of its fuselage.

The Soviet 'Buran' spaceplane makes its unmanned touchdown at Baikonur. Credit: NASA

Looks familiar – but it's actually Buran, the Shuttleski

The Shuttle has big wings because the secret US space military wanted it to: the larger wing area means that the Shuttle has what is known as "cross range" capability. This means that the Shuttle, re-entering Earth's atmosphere, doesn't have to land at a site lying directly beneath its orbital track – it can glide hypersonically 1,000 miles to one side during its descent.

The US military of decades ago planned to use this capability to carry out cunning missions in which Shuttles would lift off from Vandenberg on the California coast and orbit the planet just once at a high polar angle before re-entering to land. Without cross-range, this would bring the Shuttle down in the ocean, as the Earth would have rotated beneath it while it was circling around. But the big delta wings mean that a Shuttle would actually be capable of setting down at Vandenberg again without trouble.

Naturally the Soviets had an answer to military Shuttles – the 'Hurricane' space-fighter

The cleverness of these "Mission 3A/3B" space hops would have been that the Shuttle could avoid flying over any hostile countries – it could largely avoid flying over land at all, in fact. Thus it would never be picked up by enemy radars or telescopes and nobody would know what it had done during its brief leap into orbit. Spy satellites could be positioned without anyone knowing – in this context it might be relevant that the first of the stealthy, supposedly impossible-to-spot "Misty" surveillance sats was launched by Shuttle, though not on a secretive Mission 3A hop from Vandenberg*.

The X-37B unmanned spaceplane being prepared for launch. Credit: USAF

Wings do have a certain shuttley look to them, though ...

On a Mission 3B profile, the Shuttle would have secretly intercepted something in orbit and collected it, rather than dropping something off: nowadays the X-37B could do this too, though only a much smaller something. If that something belonged to someone other than the USA, its owners would never know what had happened to it. The snatch would happen out of sight below the horizon, above empty ocean or uninhabited terrain.

Unlike the Shuttle, the X-37B may soon fly from Vandenberg, as well as landing there. It could only satellite-nap the smallest spacecraft, and in any case this would be an unlikely mission – most unsubtle. Far likelier would be a close pass by a foreign satellite, either harvesting electronic and visual intelligence or perhaps carrying out a bit of deniable meddling – arranging for an opportune space-debris strike, say, or doing a spot of electronic interference. The target sat's owners would never be able to tell that the X-37B had been anywhere near their hardware.

So there may be a touch of warplane in the X-37B after all – or anyway there could be if the US military wanted. A second robo-spaceplane is already on order.

Evidently none of this is lost on the Russians, which is no doubt why they too have apparently done some work on an unmanned spaceplane. They ought to find such tech well within their grasp, having in fact made the first spaceplane to achieve an unmanned runway landing: the "Buran" ("Blizzard") shuttle – intended for manned operations, but whose single test spaceflight in 1988 was carried out unmanned.

The Russians, indeed, were thought at one time to be using their advanced spaceplane technology to make an overtly warlike craft: the rumoured "Uragan" ("Hurricane") space interceptor developed from the MiG-105 manned test craft was supposedly being developed at the same time as Buran. Manned, missile-armed Uragan space fighters would have been the Soviets' answer to the possible nefarious activities of military polar Shuttle missions out of Vandenberg – had these ever occurred. Modern Russian historians tend to the view that Uragan never existed – they say that the two 1987 launches which supposedly carried test craft were actually experiments associated with Buran.

It just could be that the Cold War is back in a small way, then, with the X-37B finally offering the US its polar-orbit undetectable military space mission capability and Russia perhaps resurrecting its own spaceplane-fighter technology of yesteryear.

Overall it seems likelier that in fact the US air force's plug-in, quick-launching, reusable satellite story will be the true one – or mostly, anyway. Such an effort would be just as attractive to the Russian space force, after all.

And anyway, don't bank on a Russian military spaceplane any time soon – even a pocket-sized one like the USA's. Disappointingly, Ostapenko rounded off his remarks on the Muscovite efforts by saying "as to whether we will use it, only time will tell". ®

Bootnote

*In the end no shuttles ever flew such missions: their lifting performance was not as good as had been hoped for, and they lacked the grunt to put heavy spy sats straight into polar orbits: this forfeits the helpful speed boost that an easterly launch into an equatorial orbit – as from Cape Canaveral – gets from the Earth's rotation.

Plans for extra strap-on boosters for military Shuttle flights came to nothing following the Challenger disaster of 1986.