The U.S. Air Force is balancing between losing capability and meeting an urgent request to equip Air National Guard Lockheed Martin F-16s assigned to homeland defense with active electronically scanned array (AESA) radars to detect small radar cross-section targets, such as cruise missiles.

U.S. Northern Command has issued an urgent operational need (UON) and the Air Force must decide between fitting the Block 30 F-16s assigned to aerospace control alert with a non-integrated AESA suitable for the air-to-air mission or a fully integrated radar capable of supporting all the F-16’s roles.

If the F-16s are upgraded with an air-to-air-only AESA to meet the 18-month timescale of the UON, “we will lose some capabilities over what we have now,” Maj. Gen. Timothy Ray, Air Force acquisition director for global power programs, told House Armed Services Committee hearing last week.

An air-to-air-only AESA retrofit would sacrifice air-to-ground modes in the current APG-68 mechanically scanned radar that are used when Guard F-16s are deployed in the strike role. “These aircraft are used for both warfighting and homeland defense,” testified Lt. Gen. Stanley Clarke, director of the Air National Guard.

The Air Force planned an AESA-centered upgrade for 300 Block 40-52 F-16s under the Combat Avionics Programmed Extension Suite (Capes) program. But this, along with a service life extension to increase structural life to 10,000 hr. from 8,000 hr., was canceled under sequestration budget caps.

The Air Force is still supporting the development of a fully integrated active-array radar upgrade for Taiwan’s F-16A/Bs, and in February Northrop Grumman received a production contract from Lockheed Martin for 142 SABR AESAs. Raytheon’s RACR AESA was selected for a South Korean F-16C/D upgrade, but this was canceled.

On March 6, the Air Force issued a request for information on AESAs suitable for retrofit to Block 30-52 F-16s with minimal modification. Although the Block 30 is first, “We need to develop an AESA upgrade plan for the entire fleet,” Chief of Staff Gen Mark Welsh told a congressional hearing March 17.

Welsh told the House Armed Service Committee that the Air Force has budgeted $25 million in fiscal 2016 for integration of an air-to-air-only radar, but would prefer to spend $75 million, “if we can find the money,” for a fully integrated AESA.

The projected production cost of the two retrofit options is “real close,” Welsh said: $2.8 million for air-to-air only versus $3.2 million for fully integrated, “which is the way we want to go.” Ray says a decision on how to proceed is expected “in the next two months.”

More than a new radar for homeland-defense F-16s is involved in countering small cross-section threats, Lt. Gen. James Holmes, Air Force deputy chief of staff for strategic plans and requirements, told the March 25 hearing. “It is part of a kill chain. We need surveillance and a command-and-control system.

“Those elements are falling in place here in the National Capital Region and we expect to move forward to provide a rapid capability there first, then try to find out how to expand it across the country,” he said. “It is easier to put the entire kill chain together in the National Capital Region.”

Holmes was likely referring to the U.S. Army’s Raytheon Jlens cruise-missile defense system now deployed at Aberdeen Proving Ground northeast of Washington for a long-term trial. The system comprises twin tethered aerostats carrying surveillance and targeting radars aloft at 10,000 ft.