LIHU'E, Kaua'i — The Missile Defense Agency will try to shoot two simulated enemy missiles down at once tomorrow in the latest test of the Navy's Aegis ballistic missile defense system.

A similar test was aborted in December because of an incorrect setting in the Aegis missile system aboard the Aegis cruiser USS Lake Erie. This is the 10th intercept attempt. Of the previous nine, seven resulted in successful intercepts.

The tests have been increasingly complex, and in this case, the Lake Erie will be called on to identify and deal with two threats at once.

One of them will be a simulated short-range ballistic missile fired from the ground at the Pacific Missile Range on Kaua'i. The second will be an anti-aircraft rocket dropped from a Navy aircraft and aimed at the Lake Erie.

The Lake Erie, with the help of satellite tracking, will identify the two threats at the same time, and launch separate missiles against them. It is slated to launch a Standard Missile-3 against the ballistic missile target, and the goal is for the SM-3 interceptor to actually crash into the target missile. The Lake Erie is to launch a Standard Missile-2 against the anti-aircraft rocket. In a combat situation, the SM-2 warhead would explode alongside the incoming rocket to destroy it, but it will not be rigged to explode during this test.

This test is designated FTM-11 Event 4 in the series of Aegis Ballistic Missile Defense tests. It is designed to intercept a ballistic missile in flight, and to simultaneously defend the ship against an airborne threat directed at the ship.

"The firing scenario is designed such that both targets are engaged at about the same time, intentionally stressing the crew and combat system resources," the MDA said in a fact sheet on the launches.

The U.S. Missile Defense Agency and the Navy manage the Aegis system. Their prime contractor is Lockheed Martin Maritime Systems and Sensors. Raytheon Missile Systems is the contractor for the Standard Missile.

Reach Jan TenBruggencate at jant@honoluluadvertiser.com.