WASHINGTON — A Pentagon Standard Missile (SM)-3 Block 1B interceptor engaged and destroyed a short-range target missile over the Pacific Ocean Sept. 18 in what the U.S. Missile Defense Agency (MDA) said was the fourth straight success for the sea-based system.

According to the MDA, which develops and test missile defense systems, the test was conducted under “operationally realistic” conditions in which the exact launch time and trajectory of the target missile were not known. The MDA said the target, a separating missile, “was the most difficult target engaged to date.”

At approximately 2:30 p.m. local time, the target was launched from the Pacific Missile Range Facility on Kauai, Hawaii, and flew northward over an open area of the Pacific. The target was detected by radars aboard the USS Lake Erie, which developed a firing solution via the on-board Aegis Ballistic Missile Defense System and launched two Raytheon-built SM-3s.

“The first SM-3 that was launched successfully intercepted the target warhead,” the MDA said in a Sept. 18 press release. “This was the first salvo mission of two SM-3 Block IB guided missiles launched against a single separating target.”

In a press release dated Sept. 18, Tucson, Ariz.-based Raytheon Missile Systems said the second interceptor was intended to test the Aegis system’s ability to launch multiple times against a threat. It did not have an intercept role in the test, Raytheon said.

MDA spokesman Rick Lehner said the test cost $31 million including the two interceptors, the target, and range and sensor support.

It was the fourth consecutive intercept for the SM-3 Block 1B, which is still in developmental testing and is yet to be deployed operationally. The Block 1B, an upgrade to the SM-3 1A now in service aboard Navy ships, failed in a September 2011 intercept test.

Warren Ferster is the Editor-in-Chief of SpaceNews and is responsible for all the news and editorial coverage in the weekly newspaper, the spacenews.com Web site and variety of specialty publications such as show dailies. He manages a staff of seven reporters...