WASHINGTON — The U.S. Missile Defense Agency is revisiting concepts from a long-range interceptor program shuttered by the White House in 2013 as it weighs how to proceed with one of its top priorities, a redesigned kill vehicle, industry officials say.

Earlier in September, MDA officials asked Lockheed Martin, Boeing and Raytheon to refine kill vehicle concepts they were working on in 2011 for a Standard Missile (SM)-3 Block 2B interceptor that would be installed in Poland to help defend Europe and bolster the U.S. territorial shield against threats originating from the Middle East. But the White House announced in March 2013 that the Block 2B development would be restructured to help cover the cost of beefing up U.S.-based defenses against the North Korean missile threat.

The Block 2B money was redirected to various technology projects and development of the Common Kill Vehicle, which would serve as the spear end of both the Ground Based Interceptor and SM-3, two of the main interceptors in MDA’s emerging global missile shield. The MDA, in budget documents sent to Congress early last year, said  restructuring the Block 2B effort would “allow the Department to evaluate new technologies, system architectures, and component design, aimed at improvements in targeting and lethality.”

Industry officials say the MDA formalized the changes last November by modifying the Block 2B concept development contracts it awarded in April 2011 to Lockheed Martin Space Systems of Sunnyvale, California, Boeing Defense, Space & Security of St. Louis, and Raytheon Missile Systems of Tucson, Arizona.

All three companies submitted kill vehicle concepts in March. The MDA reviewed the concepts and, earlier in September, suggested revisions that are covered under contracts that now run through December, industry officials said.

Doug Graham, vice president of advanced programs for Lockheed Martin’s Strategic and Missile Defense Systems unit, mentioned the study effort during a Sept. 23 luncheon here, saying the revisions MDA suggested reflect “some of the updated requirements that the Missile Defense Agency is doing.”

MDA spokesman Richard Lehner did not respond to a request for comment before press time.

MDA has given Boeing, Lockheed and Raytheon until December to submit their concept revisions, industry sources said, and told the companies to expect a response in March.

However, what that response could entail is unclear, the sources said.

The MDA’s director, Navy Vice Adm. James Syring, has said a redesigned kill vehicle is one of his top three priorities and that the agency could hold a limited or open competition for a new design, task Raytheon to modify the existing design or pursue another path entirely.

The MDA’s interest in a redesigned kill vehicle has grown in the wake of a string of intercept test failures involving the Ground-based Midcourse Defense system in recent years. Two failures were attributed, in whole or in part, to problems with the current Raytheon kill vehicle hardware, which Syring is quick to point out was rushed through development — or, as a Raytheon spokeswoman said, “was deployed in 2004 as a prototype because of urgent national defense priorities.

“We’ve learned a lot in the past decade about making consistent performing kill vehicles with high reliability through our SM-3 program, which was allowed to mature through a typical ‘crawl, walk, run’ engineering design process,” Raytheon spokeswoman Heather Uberuaga said in a Sept. 25 email. “We think there are a lot of lessons learned from the SM-3 program that can be applied to a redesigned [kill vehicle].”

Lockheed Martin spokeswoman Lynn Fisher said Sept. 25 that Lockheed’s concept work is drawing on technology used for its regional missile defense system, the Terminal High Altitude Area Defense, the company’s experience as prime contractor for the since-canceled Multiple Kill Vehicle program, and internal research and development efforts.

Dexter Henson, a spokesman for Boeing — the prime contractor for the overall Ground-based Midcourse Defense system — did not respond by press time Sept. 26. Boeing is working with Israel Aerospace Industries on an anti-ballistic missile called Arrow-3 that uses pivoting optical sensors and its own upper-stage kick motor instead of separate control rockets to steer itself into incoming targets.

Mike Gruss covers military space issues, including the U.S. Air Force and Missile Defense Agency, for SpaceNews. He is a graduate of Miami University in Oxford, Ohio.