What's got a 500-foot wingspan, flies at 90,000 feet and stays up in the air for five years without ever touching the ground?

If the Pentagon has its way, it'll be the Vulture, its planned long-, long-, long-range unmanned surveillance and communication aircraft.

The Defense Advanced Research Projects Agency last week awarded contracts to Manassas, Va.-based Aurora Flight Services and top defense contractors Boeing and Lockheed Martin to develop working prototypes of the Vulture, according to the aerospace news service Flight.

A Northrup Grumman proposal was rejected.

• Click here to see a video of what the Vulture might look like in action, complete with an '80s triumphal-metal soundtrack.

What the Pentagon wants is essentially a maneuverable satellite replacement: a fixed-wing, heavier-than-air craft that's high enough to "see" large swaths of the Earth at once, but one that can also reposition itself to circle over new areas of interest, something satellites in fixed orbits can't do.

It has to be able carry a 1,000-pound payload, battle stratospheric winds, generate a continuous 5 kilowatts of electricity — and it can't use nuclear power to do so.

"We want to completely change the paradigm of how we think of aircraft," Vulture project manager Daniel Newman tells Flight. "We would no longer define an aircraft by the launch, recover, maintain, launch cycle."

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Aurora's concept, called Odysseus, will be unveiled at a press conference Wednesday. It envisions three 50-meter (164-foot) segments taking off independently, then linking up in flight.

Each segment will be powered by solar panels stretched out along the wings, and they will be able to pivot to maximize sunlight collection.

Boeing and Lockheed Martin's proposals are not yet public, but they might include segments that could independently land and relaunch for servicing while the main unit stays aloft.

Fuel cells with regular aerial refueling might be an alternative to solar panels to power the craft.

• Click here for Flight's conversation with DARPA officials, here for its interview with an Aurora engineer and here for last summer's DARPA solicitation for bids for the Vulture prototype.