WASHINGTON — A move to develop a new family of sensors to replace aging air search radars on major US Navy ships has merged with the need for a lower-cost system on future aircraft carriers, officials revealed last week.

Shoved aside in the shuffle is an expensive, high-powered radar system that now will be installed on only one ship.

Northrop Grumman and Raytheon are each at work on a new enterprise air surveillance radar (EASR) intended to replace SPS-48 and SPS-49 rotating radars on future ships and ships now in the fleet, primarily aircraft carriers and big-deck amphibious assault ships.

Each of the companies is working under a $6 million study and demonstration contract from the Office of Naval Research (ONR). The ONR studies, according to a Northrop press release, "will examine how an existing radar concept can be evolved to meet the EASR requirements." Northrop's contract was awarded in November 2013, while the Raytheon contract came last June.

Now, according to the Navy's admiral in charge of carrier construction, the EASR will be installed on the second ship of the Gerald R. Ford class, the John F. Kennedy, under construction at Newport News Shipbuilding. The EASR would replace the dual-band radar (DBR), a powerful system once intended to be installed on all Ford-class carriers and Zumwalt-class destroyers, but now reduced to just the Ford.

"We had already made a decision to truncate the DBR to only two ships," Rear Adm. Thomas Moore, program executive officer for aircraft carriers, told reporters March 18. That meant a search was on for a lower-cost radar to fit on the Enterprise, third ship of the new class.

But in the fall of 2013, his office began looking at the possibility of fitting the EASR on the Kennedy. The move, Moore said, will potentially shave $180 million off the Kennedy's cost.

The carrier won't be the first ship to receive the new radar, Moore said. Rather, the yet-to-be-named LHA 8 assault ship, intended to be funded in 2017, will first carry it to sea.

"This will be equipment already in the fleet," he declared. "The EASR radar we choose will be an off-the-shelf radar that we will tailor to the ships."

But whether it's Northrop or Raytheon, the EASR radar has not yet been fielded. Northrop's EASR concept is being developed from a ground radar, the TPS-80 ground /air task-oriented radar (G/ATOR), under development for the US Marine Corps.

Raytheon's radar modular assembly architecture is derived from the air and missile defense radar (AMDR) now under development for the Navy to replace SPY-1 radars in new Aegis combat systems.

The EASR, like the AMDR, is intended to be a scalable family of radars tailored to suit different sizes of ships. Unlike AMDR, EASR is planned to be backfitted on existing ships to replace older radars.

Raytheon is also developing the DBR. Northrop, along with Lockheed Martin, was a losing competitor in the AMDR decision, awarded in 2013.

With the Ford now becoming the only ship to operate the full DBR, the Navy will likely have difficulty training maintainers and servicing the system over the ship's planned 50-year service life. Moore said no decision has been made on backfitting the EASR onto the Ford. "We'll cross that bridge when we come to it," he said.

The DBR, he noted, is simply more radar than the carriers need. "It's hard for me to imagine that if there hadn't been the DDG 1000 program we would have picked the DBR," he opined.

The EASR will meet most of the carrier's requirements, although there will be some capability shortfalls to be addressed.

"EASR does basic functions — volume search, carrier traffic control," he said. "The DBR is much more powerful, especially in detect-to-engage mode, and it can do fire control. EASR cannot do that, so we'll have to add SPQ-9B radars. DBR also does periscope detection, and we'll have to look at that."

The Ford is tracking toward delivery in March 2016, Moore said. Construction on the Kennedy has already begun, but the ship won't be delivered before June 2022. And even then, the ship won't have a complete combat system. Rather, the Navy plans to install a more modern and up-to-date system after the ship is in service, but before replacing the carrier Nimitz among the fleet's deployable flattops. The older carrier is set to retire in 2025.

"We can have Newport News deliver the ship in 2022," he said, "then come back in for a second phase and install the combat system and C4I (command, control, communications and computers and intelligence) gear," he said. One of the systems that would be installed post-delivery is the EASR.

"If I'd have to deliver the complete ship in 2022, I would have to go back to the DBR radar. Now I can compete that," Moore said. "In the nine years it takes us to build a carrier, combat system stuff can become obsolete. If we wait to the second phase we can get another two-to-three generations of technology — and we don't have to update as soon" later in her career.

Construction is proceeding well on the Ford, Moore noted, and the ship is holding under its cost cap of $12.887 billion. Two of the four electromagnetic aircraft launch system (EMALS) catapults have been installed, and testing is going well. "I would rate that as green," he said, indicating satisfaction.

The one outstanding issue still to be met is the ship's new advanced arresting gear (AAG), under development by General Atomics.

"AAG is the one thing I am watching the most," he said. "The period where the shipyard finishes testing goes slightly past the end of March, and we're working to bring that forward.

"We've worked out all the problems with the water twister and have installed that on the ship," he said, referring to a key component that needed to be redesigned, setting AAG development back a couple of years. "The problem now is concurrent testing at [the Navy's test facility in Lakehurst, New Jersey] while we're installing the system on the ship."

Twitter: @CavasShips