The U.S. Navy has apparently found a way to reduce some of the early risk and cost for its Air and Missile Defense Radar (AMDR) by considering a phased approach to the deployment of the X-band sensor for the suite, according to industry sources’ initial analysis of the draft request for proposals (RFP).

AMDR is one of the cornerstones of the Navy’s—and nation’s—plans for ballistic missile defense for the fleet and allies abroad. The AMDR suite consists of an S-band radar, X-band radar and a Radar Suite Controller. AMDR-S is a developmental Integrated Air and Missile Defense radar providing sensitivity for long-range detection and engagement of advanced threats. The X-band radar is a horizon-search radar based on existing technology.

As this week’s draft RFP notes, AMDR is planned for installation aboard the Flight III DDG-51 Arleigh Burke-class guided missile destroyer. But defense analysts have questioned whether it would prove too expensive to develop and deploy AMDR on that version of the ship, given the current technology and ship restraints. It appears, industry sources say, the Navy is trying to keep a lid on costs and risk with X-band development on AMDR.

For the first dozen ships, the AMDR suite will integrate with the AN/SPQ-9B X-band radar. Starting with the 13th shipset, the AMDR-X, a phased-array non-developmental X-band radar, will be incorporated into the AMDR suite, sources note. The first dozen ships should anchor the fleet until about fiscal 2024.

SPQ-9B is a pulse Doppler radar using the transmitter from the F-16’s APG-68. The latest version, sources note, is SPQ-9B-3D, which adds a 3-D volume air search mode. SPQ-9B was installed as original equipment on the LPD-17s—the two newest LHD amphibious ships—and latest Nimitz-class aircraft carriers.

Sources say the AN/SPQ-9B will help address the fleet’s urgent need for the powerful long-range radar to generate precise early tracks. The Navy then has the flexibility, sources say, to go with SPY-3 if adequate power and funding is available, or with SPY-5 if not.

Navy officials remain optimistic they will be able get all the technology development and capability for AMDR as planned. Key technology for the AMDR is advancing more quickly than the service brass had anticipated, says Rear Adm. James Syring, the program executive officer for Integrated Defense Systems.

Especially promising, Syring says, has been the development of Gallium Nitride (GaN) semiconductor technology to address weight, cooling and operational needs to fit AMDR on Flight III DDG-51s. “A lot has been written (about the AMDR’s future,” Syring says. “A lot that’s incorrect.”

Thanks to GaN technology and other developments, he says, the Navy should be able to put AMDR on Flight III ships and have adequate growth for coolant equipment and needs.

Syring says a final RFP should be ready within three to four weeks, with a source selection by the end of the year.