The U.S. Navy is asking three companies each to design an aircraft that can conduct simultaneous intelligence-gathering missions that were considered impractical, perhaps impossible, even a couple of years ago.

In particular, the Navy wants a single, EPX aircraft that can use a powerful radar and at the same time operate an array of sensitive receivers that can collect faint electronic emissions or communications from hundreds of miles away. The multisource information would be fused to locate and identify objects of interest as fleeting and elusive as the low-power cell and satellite telephones used by terrorists and insurgents.

Requirements for an EP-3 replacement would add “organic systems that can do accurate, definitive targeting,” says Paul Summers, Boeing’s director of airborne signals intelligence campaigns. “Radar will be part of the sensor suite.” What’s not defined is the type of radar or how it would be used. That means the “field of regard, instantaneous field of view, power out and range” also haven’t been determined, Summers says.

Boeing’s concept of an EP-3 replacement, based on the 737 with a conventional antenna layout, may change radically when advanced conformal arrays are added.Credit: BOEING CONCEPT

Lockheed Martin adds mystery to its effort by saying it will “draw on the depth and breadth of its Advanced Development Programs” (ADP) organization which gained fame as the “Skunk Works” and of late has specialized in stealthy, unmanned aircraft.

“Expendable systems,” which may include stealthy unmanned air vehicles small enough to be launched by EPX to fly into enemy air defenses, are “becoming smaller and more capable than ever before,” says Frank Blesi, ADP’s EPX study lead. “By ensuring that EPX can employ expendable systems in the basic concept design, we reduce the cost and risk of integration.”

The Navy’s refinement and apparent expansion of its requirements since last summer has shocked contractors.

“It’s a changed doctrine with new capabilities that include electro-optical/infrared [sensors], synthetic aperture radar/inverse SAR, maritime moving-target indicating, multi-intelligence targeting, wideband satellite communications and searching for [global war on terrorism]-type signals,” says Dennis Hayden, Northrop Grumman’s EPX campaign manager.

The need for a simultaneous active/passive system is part of a just-released set of requirements from the Navy with which teams led by prime contractors Boeing, Lockheed Martin and Northrop Grumman are wrestling.

Two advanced technologies under consideration for EPX are the active electronically scanned array (AESA) radar (with greater range and target discrimination than manually scanned radars) and widespread use of conformal antennas attached to the aircraft’s exterior.

“Radar is going to be a must,” Hayden says. “Any product, sensor or system that can perform multiple jobs [like AESA arrays for sensing, electronic attack and wideband communications] will be attractive.”