Aircraft Manufacturers Bring Different Capabilities to BAMS Starting Line

Sea Power, Jun 2004 by Burgess, Richard R

The two top contenders for a novel Navy program to buy robotic planes for ocean surveillance are offering substantially different aircraft - and operating philosophies to earn a larger stake in the military's market for unmanned aerial vehicles (UAVs).

Northrop Grumman proffers a version of its highendurance, long-range Global Hawk that would stay at altitudes of about 60,000 feet as it patrols huge swaths of ocean searching for targets of opportunity. Lockheed Martin's Mariner would patrol at 50,000 feet, but descend below cloud cover to use electro-optical and infrared sensors.

Either approach could prevail, because the Navy's specific requirements for the Broad-Area Maritime Surveillance (BAMS) system are expressed only in broad terms that eschew mention of specific sensors or other equipment. A Navy official said that it would be left to the bidding contractors to propose their solutions to the requirements of "sensing targets at sea."

The service plans to issue a request for proposals to industry this month. Operational needs such as targets, ranges, search rates and other parameters are classified, said Capt. Daniel Duquette, the Navy's requirements officer for unmanned aerial systems. He summed up the requirements as "persistent surveillance of the open ocean and a look in over the littoral."

The number of UAVs required would depend on which proposal is selected for further development. The Navy has proposed basing UAVs at five patrol-plane bases across the world to cover the oceans.

The next milestone in the program, scheduled for the spring of 2005, will be to choose a design for further development.

In addition to Northrop Grumman and Lockheed Martin, General Dynamics' Gulfstream may propose an unmanned version of its Gulfstream 550 executive jet.

Northrop Grumman is offering the RQ-4B derivative of its RQ-4A Global Hawk, a long-range, high-altitude UAV in Air Force service. The company claims that a cell of three Global Hawks - each with an endurance of 36 hours - can successively provide for 30 days continuous 24-hour surveillance of an area at least 2,000 nautical miles from its base. Thomas Twomey, Northrop Grumman's business manager for BAMS, estimates the Navy would need between 37 and 50 Global Hawks to fulfill its worldwide requirements.

The Global Hawk flies at 60,000 feet, out of range of most surface-to-air-missiles, higher than conflicting airliner traffic and above the fastest winds, a factor that improves its range and endurance.

Lockheed Martin's Mariner is a derivative of the relatively small MQ-9 Predator B built by General Atomics, but with longer wings and increased fuel capacity for highaltitude performance. The Mariner, with an endurance of 49 hours and the ability to operate for 24 hours on station at least 2,000 nautical miles away, is designed to fly at 50,000 feet and below for optimum radar performance, said Alex S. Hill, Lockheed Martin's business manager for the program.

He said the shallower gazing angles are necessary for target identification. Hill also said the UAV often would descend below cloud cover to use electro-optical and infrared sensors, and that a turboprop engine like the one on the Mariner would be more efficient for altitude changes.

During tests in April funded by Lockheed Martin, a Predator B UAV outfitted with a Raytheon Seaview radar was flown in racetrack patterns off the California coast to help determine optimal surveillance altitudes. A demonstration for the Coast Guard is scheduled this month off Alaska, this time using a Telephonies radar.

Hill said that Lockheed Martin's BAMS proposal offers the "lowest total ownership cost."

Northrop Grumman claims the Global Hawk BAMS offers the best value at the lowest risk.

Two RQ-4A Global Hawks configured with radar optimized for maritime surveillance are scheduled to participate in the Global Hawk Maritime Demonstration beginning in 2005. The demonstration - separate from the BAMS program - fits within the chief of naval operations' Sea Trial concept of experimentation.

"Our goal is to get this in the hands of the fleet as soon as soon as we can," Duquette said.

Navy officials declined to give a cost estimate of the BAMS program, noting it is "only one of the factors in the source selection process" and would depend on which solution was selected.

The Navy's proposed fiscal year 2005 budget plan proposes building two BAMS UAVs in 2007 and four each in 2008 and 2009. The Navy has requested $113.4 million in research, development, test and evaluation funding for high-endurance UAVs in 2005.

By RICHARD R. BURGESS

Managing Editor