The Pentagon has approved full-rate production of the Standard Missile-6, a next-generation ship defense missile developed by Tucson-based Raytheon Missile Systems.

The decision by the Defense Acquisition Board paves the way for the SM-6 to reach initial operating capability later this year, the company said. Full-rate production deliveries are expected to start in April 2015, three months ahead of schedule, Raytheon said.

In February, Raytheon delivered the first SM-6 from its new, $75 million, 70,000 square-foot SM-6 and Standard Missile-3 all-up-round production facility at Redstone Arsenal in Huntsville, Ala. Some engineering and component work is still done in Tucson.

The latest in the Standard Missile series of ship-defense missiles first developed in the 1960s, the SM-6 adds a rocket booster for extended range as well as onboard “active” radar-targeting adapted from Raytheon’s Advanced Medium-Range Air-to-Air Missile (AMRAAM).

The active radar enables the SM-6 to detect and track targets itself “over the horizon,” out of reach of the firing ship's sensors.