A planned Dec. 11, 2009, intercept test of the U.S. Missile Defense Agency’s (MDA)’s Terminal High Altitude Area Defense (THAAD) missile defense system was halted when the target missile’s flight computer aborted its launch sequence for a yet-to-be-determined reason, an agency spokesman said Dec. 17.

The THAAD interceptor was to be fired from the U.S. Navy’s Pacific Missile Range Facility at Kauai, Hawaii. The target, built by Coleman Aerospace of Orlando, Fla., a subsidiary of L3 Communications, was deployed from a C-17 transport aircraft over the Pacific Ocean when its onboard computer failed to send the command to ignite its rocket motor, MDA spokesman Rick Lehner said in an e-mail. The target missile fell into the Pacific Ocean and was not recovered. The THAAD fire control system, however, continued with a series of successful simulations and all components were certified to be in working order, according to a Dec. 11 MDA press release.

The THAAD system was developed to intercept short-, medium- and intermediate-range ballistic missiles for regional defense. The system has gone six-for-six in intercept attempts since 2005 after a nearly six-year hiatus from flight testing that followed a string of test failures. Lockheed Martin Missiles and Fire Control of Dallas is the THAAD prime contractor.