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US X-37B robot minishuttle: 'Secret space warplane'?

No, but it could do some naughty orbital stuff

Why would a re-usable vehicle need wings specifically?

The USAF has remained fairly tight-lipped about the X-37B, refusing even to reveal how much it costs as it is funded from the classified (or "black") budget. Programme managers won't reveal anything about tomorrow's payload or even how long the little spaceplane is to stay up before landing at either Edwards or Vandenberg in California. However the Rapid Capabilities Office does say:

Actual length for the first mission will depend on the meeting the mission objectives, which consists of checkout and performance characteristics of the spacecraft systems.

Objectives of the OTV [Orbital Test Vehicle] program include space experimentation, risk reduction and concept of operations development for reusable space vehicle technologies.

Spokesmen have also tended to play up the fact that the X-37B is intended to be an "economically viable experimental test platform", as it is supposed to be much more advanced in terms of turnaround time, heat shields and so on than the Shuttle.

This sort of innocuous talk, combined with the partly civilian history of the project, would tend to indicate a simple tech prototype, not really aimed at any specific military mission. Certainly the Iranian state-funded media channel Press TV's description of the craft as a "secret space warplane" seems a trifle alarmist.

Even so, the fact that the X-37B has a strong heat shield and wings, relatively smaller but similarly shaped to those of the space shuttle, is interesting to military space buffs. Perhaps the main reason that the shuttle had such big wings and such a tough (though as it turned out somewhat unreliable) heat shield was that the US Air Force wanted it to. Consider this quote from the Columbia accident investigation report:

The Department of Defense wanted the Shuttle to carry a 40,000-pound payload in a 60-foot-long payload bay and, on some missions, launch and return to a West Coast launch site after a single polar orbit. Since the Earth's surface - including the runway on which the Shuttle was to land - would rotate during that orbit, the Shuttle would need to maneuver 1,100 miles to the east during re-entry. This "cross-range" requirement meant the Orbiter required large delta-shaped wings and a more robust thermal protection system to shield it from the heat of re-entry.

It's often forgotten nowadays that the Shuttle was originally intended not just for NASA operations from Cape Canaveral, but also for military operations from a dedicated complex at Vandenberg Airforce Base in California. This would have launched military shuttles into polar orbits rather than generally easterly, low-angle ones as from Florida.

Polar-type orbits tend to be favoured for spy satellites, as the Earth turns beneath the circling spacecraft. This allows an orbital spyeye to pass over any given spot regularly, observing events of interest below.

The fact that the Earth turns, however, would normally mean that a spacecraft lifting off from Vandenberg and orbiting once around would then be above the Pacific, with no hope of returning to its base until many more orbits had passed and the western United States came round again. By that point such a spacecraft would very likely have been seen by suitably alert watchers around the world and details of its track worked out - so, perhaps, giving useful clues as to the path of anything it might have dropped off or picked up.

Not so in the case of a craft with heatproof wings and "cross range" capability, however. A shuttle would have been able to lift off from Vandenberg, orbit at a high angle from the Equator once - during which time it could deploy something or pick something up - and then re-enter, using its wings to bend its re-entry track east and so put down again in California, never having overflown any nation of concern.

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