WASHINGTON — When the Sea-Based X-Band radar is dry docked for an overhaul in roughly the 2020 time frame, it won't affect the U.S. capability to detect any missile threats in the Pacific, according to the Missile Defense Agency.

During a House Armed Services Strategic Forces Subcommittee hearing Wednesday, lawmakers raised concern that the SBX radar would be out of commission before the Missile Defense Agency is able to field a new medium-range radar for missile threat detection in Hawaii.

The MDA, in its fiscal year 2018 budget request, is asking for $21 million to begin a competition for a homeland defense radar to be positioned in Hawaii. MDA plans to compete and award a Pacific radar contract in FY18 and deliver an initial capability by FY23, according to budget documents.

While the SBX — the world's largest phased-array X-band radar on top of a mobile, ocean-faring, semi-submersible oil platform — will see longer days at sea in FY18, the expectation is it will need to be dry-docked for a major overhaul in roughly 2020. The MDA has requested $130.7 million for which part of the funds will cover extending its on-station time from 120 to 330 days at sea at the request of U.S. Northern Command and U.S. Pacific Command in defense of the homeland.

There’s also a concern the Hawaii radar might not reach IOC by 2023 because a site for the radar has yet to be selected and would have to undergo an environmental impact study, which historically has a tendency to take longer than predicted and delay military construction schedules.

MDA Director Vice Adm. James Syring told lawmakers during the hearing that there are also opportunities to push back the schedule to dry dock SBX by a couple of years.

"We can work with operators and the military combatant commands in terms of what risk they are willing to accept and we will do underwater hull surveys to assess the life of basically how the vessel is doing," Syring said. "There can be ways to not only take risk on when that dry dock appears or it’s conducted with periodic maintenance that can be done during the in-port period short of a full dry dock."

The decision to dry dock SBX in 2020 or later could be based on how the Hawaii radar is progressing as well as the fielding of the Long-Range Discrimination Radar in Alaska, Syring said, but it would be up to the combatant commanders.

The LRDR is a midcourse sensor that will improve ballistic missile defense system target discrimination capability while supporting more efficient use of the Ground-Based Midcourse Defense System interceptor inventory. The GMD system consists of 44 interceptors in Alaska and California ready to fire against an incoming Intercontinental BMD threat from North Korea or Iran.

The LRDR is scheduled to begin operation in 2020.

But even if the SBX is dry docked and the Hawaii radar is not yet in place, Hawaii and the continental U.S. are still protected from current ICBM threats by the GMD system in Alaska and California, ground-, sea- and space-based sensors and redundant command, control and communications systems, according to MDA.

The Hawaii radar is not being built to replace any system, but as an added layer of defense, the agency emphasized in a statement to Defense News.

Meanwhile, MDA is looking at six or seven locations in Hawaii for the radar but has not yet determined which site would be the most appropriate, according to Syring.

The Pacific Missile Range Facility in Kauai is on the table as a possible site. "The Navy completely understands the need for the radar and we are looking closely with them on what operational restrictions would have to be in place at PMRF," Syring said.

Jen Judson is an award-winning journalist covering land warfare for Defense News. She has also worked for Politico and Inside Defense. She holds a Master of Science degree in journalism from Boston University and a Bachelor of Arts degree from Kenyon College.

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