LIHU'E, Kaua'i — The technology used to knock out a target missile northwest of Kaua'i yesterday will be installed on 18 Navy ships within three years, a military official said after yesterday's successful test.

"We're still going over the data, but there are all indications that both (defensive missiles) were very successful in hitting the target," said Rear Admiral Brad Hicks, the Missile Defense Agency's Aegis program director, in a telephone news conference.

Yesterday's test was only the second time a Navy ship has fired a modified Standard Missile-2 Block IV to destroy a ballistic missile in its terminal phase, the last minute of flight.

Aegis defense systems have done what they were built for 12 of 14 times — taking out ballistic missiles during their mid-course cruise through space.

In the last two years, the Navy and Missile Defense Agency have modified Aegis and SM-2 Block IV missiles to destroy ballistic missiles in their terminal phase. The development has cost about $120 million through yesterday's $40 million test, Hicks said.

"We're pretty excited about it," Hicks said. "This gives the warfighter the capability he's been asking for."

By October, the Navy will begin installing new software on each of its 18 Aegis-equipped ships, Hicks said. Preparing each ship will cost about $150,000, he said.

"This allows us to kill (missiles) in the atmosphere and in space" from Aegis ships, he said.

However, Hicks said, using the SM-2 missiles for terminal ballistic missile defense is "a gap filler" while a ship-based version of the Patriot missile is built. Patriots are designed to shoot down missiles as they near their destination.

The Army uses a land-based version of the Patriot.

"If I don't have a Patriot nearby on a shore station to do a short-range threat, near the defended area, I have nothing," Hicks said. "The flexibility of having a ship to complement the Patriot, or to be there when it can't be, is very high on a warfighter priority."

Here is the Missile Defense Agency's timeline for yesterday's successful test: