WASHINGTON — The US Air Force plans to award Raytheon and Northrop Grumman two sole-source contracts to mature radar designs for the Joint Surveillance Target Attack Radar System, the latest step in the service's ongoing effort to recapitalize its ground surveillance fleet.

The Air Force's effort to develop a modern active electronically scanned array, or AESA, radar for the next-generation JSTARS is being conducted in parallel with the service's search for a business jet solution to replace the aging E-8C fleet, currently being flown to its limit in the Middle East and elsewhere.

The legacy JSTARS, a militarized Boeing 707-300 airframe produced by Northrop, has long-range radars that provide theater ground and air commanders critical ground surveillance to support attack operations. Its most prominent feature is a long, canoe-shaped space under the forward fuselage that houses a 24-foot, side-looking phased array antenna.

The radar contract announcement is not a down select, as Raytheon and Northrop are the only two original equipment manufacturers capable of meeting the Air Force's requirements for the JSTARS radar, service spokesman Justin Oakes told Defense News in a Friday email.

The Air Force will award the companies separate radar "technical maturation and risk reduction" contracts to continue development of the radar subsystem design and reduce the integration risk with JSTARS recap, according to a notice posted on the Federal Business Opportunities website Jan. 26. The exact value of the contracts will be finalized upon completion of the negotiations with the radar manufacturers, Oakes said.

The use of a modern AESA radar will allow the JSTARS recapitalization to fulfill the mission while operating on a much smaller, business jet airframe, according to the Air Force.

"Although the JSTARS radar was state-of-the-art when it was developed, technology has advanced significantly since its introduction in 1991," said Brian Carr, JSTARS Recapitalization Radar deputy IPT lead, in a Jan. 26 Air Force statement. "JSTARS Recapitalization is poised to leverage the technological advancements that have lowered the cost and enabled the use of [AESA] radars."

Meanwhile, three distinct industry teams are vying to build the JSTARS airframe. Separately from the radar competition, Northrop is teamed with Gulfstream and its G550 business jet, with L-3 helping with integration. Lockheed Martin is working with Bombardier on a proposal based on the Canadian company's Global 6,000 business jet. And Boeing is offering a modified version of its 737-700 commercial airliner.

The three teams are currently moving forward with additional pre-engineering, manufacturing and development work on the JSTARS business jet solution after the Pentagon in December approved the program to move into the next phase of the acquisition cycle. The so-called Milestone A decision will allow program officials to exercise about $45 million on options on the three separate EMD contracts for additional reviews and subsystem prototype demonstrations over the next six months.

Email: lseligman@defensenews.com

Twitter: @laraseligman

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