Global Hawk developers also say that specially designed encryption programs would prevent adversaries from severing communications between the operator and the aircraft.
"You have the same flexibility," said Gary S. Martin, director of development, testing and evaluation for the Air Force. "We can change everything on the fly."
Both sides agree that some kind of airborne military reconnaissance is needed despite growing reliance on spy satellites. Orbiting satellites cannot hover over a target, and their scheduled routes are detectable. The Iraqi army, for instance, surreptitiously built bunkers by timing construction activity to avoid scheduled passes overhead by spy satellites.
Reconnaissance planes, however, can fly to a target at any time and stay aloft over the area for hours. As such, the U-2 was a breakthrough for military intelligence. But the plane, which first took flight in 1955, is beginning to feel the strain of its age.
A recent assessment by the Congressional Research Service, a nonpartisan research agency for Congress, noted that the hardships involved in flying U-2s "may contribute to significant [pilot] retention problems that could affect overall capabilities."
The December report said there are only 50 pilots qualified to fly the U-2, which is notoriously difficult to handle. The plane is called the "Dragon Lady" because of its unforgiving handling characteristics at high altitude. Significant training is required to help pilots ward off profuse sweating, fatigue and dizziness caused by 10-hour missions in pressure suits like those worn by astronauts.
The Air Force already has retired one U-2 successor, the high-speed SR-71, which flew at three times the speed of sound. The plane was deemed too costly to operate and no longer needed in the post-Cold War period. Many more U-2s were built, the most recent a batch of planes produced in the 1980s in Burbank.
Still, the report said that although Global Hawk "appears to offer some advantages over the U-2," it does not currently match the U-2's intelligence-gathering capabilities. The U-2 can carry double the payload--radar, sensors and other reconnaissance equipment--of the Global Hawk.
Air Force officials say their goal is to quickly get Global Hawk's capabilities up to par with that of the latest U-2 by pushing for funding to develop new sensor technologies. One advantage of the Global Hawk is that it can linger over a target for 24 hours, a highly appealing capability for intelligence-gathering.
"It would also be truly global," said Robert Chiota, manager for business development at Raytheon. "It could be operating over South Korea looking at North Korea and transmit images that it has collected to Virginia and then down to the ground commands in South Korea within seconds."
Development of Global Hawk has not been without setbacks, however, and comes after more than two decades of expensive failed experiments in different forms of unmanned recon planes.
In the late 1980s, the Army spent more than $1 billion before scrapping the Aquila low-altitude battlefield UAV after it successfully completed its mission in only seven of 105 test flights. An additional $2.1 billion was spent developing the Hunter UAV, which was terminated four years ago after several crashes.
Last year, the Pentagon killed still another unmanned aircraft program called Dark Star, a stealth version of the Global Hawk, after reportedly secretly spending $850 million on it. The $400-million price tag for each of Lockheed Martin's Dark Star UAVs was deemed too high, as was the risk of losing one--loaded with America's most-advanced technology--over hostile territory.
In May 1999, a Global Hawk prototype crashed during a flight at China Lake Naval Weapons Center when it inadvertently received a test signal to terminate the flight, illustrating its vulnerability to human error and raising concerns among civilian aviation officials.
Ironically, although a pilotless vehicle is seen as beneficial in a combat zone, it has raised concerns among U.S. and foreign air-control officials who fear that an unforeseen emergency, such as an engine burnout, could bring it down over a populated area. The UAV would be less able to take corrective action, they say.
But Northrop officials say that in addition to a ground operator who could take control of the plane, there is a destruct mechanism that could destroy the craft before it crashed.
The Air Force has spent $760 million to develop and build the initial eight planes, two of which are in assembly and scheduled for delivery in 2002. The plan calls for building two airplanes annually for the next six years, eventually purchasing 40 to 45 by 2010, and 66 altogether.
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A Look at Global Hawk
With its long wingspan, the Global Hawk can hover over an area for 24 hours as its sophisticated sensors give military commanders a view of an area the size of the state of Illinois, day or night, cloudy or clear. More than 1,900 radar, optical and infrared images can be taken during a mission and instantly sent via satellite to ground troops nearby or to a command center halfway around the world.
Outfitting the premier spy plane:
* Northrop Grumman Corp., Century City: prime contractor and system integrator; also builds the fuselage and assembles the aircraft in Palmdale.
* Raytheon Co., El Segundo: supplies the optical, infrared and radar sensors as well as the decoys that can be deployed to divert an enemy missile.
* Litton Industries, Woodland Hills: navigation equipment with global positioning system.
Research Service, Northrop Grumman; photo courtesy of Northrop Grumman Corp.