The Pentagon has growing faith in Raytheon's Standard Missile-3 as a shield against evolving ballistic-missile threats, the nation's top missile-defense officer said Thursday at an event in Tucson.

"We have growing confidence in these weapon systems, in large part due to their successful testing record," Vice Adm. James Syring, director of the U.S. Missile Defense Agency, said at an event at Raytheon Missile Systems marking the 60th anniversary of the Standard Missile series of naval weapons.

Syring, who became missile-defense chief last fall, cited 25 of 31 successful test intercepts by various versions of the SM-3 since 2002, including a critical intercept last week by the latest SM-3 version.

He said nine U.S. guided-missile cruisers and destroyers are currently sailing with SM-3 interceptors aboard around Europe, the Middle East and the Asian Pacific.

"The more flexible our missile defense is, the more prepared and the more capable we will be in the face of an increasingly dangerous threat," Syring said.

The Standard Missile series traces its roots back to the Terrier, Talos and Tartar guided ship-defense missiles developed in the 1950s.

But Thursday's event at Raytheon's airport plant complex - which drew a crowd of about 300 company and military officials and VIPs from as far away as Saudi Arabia - was as much about the future as it was about the past.

The Standard Missile has moved "beyond the protection of navies to the defense of nations," Raytheon Missile Systems President Taylor Lawrence said at the event, featuring giant videos and fire-spewing missile mock-ups in a cavernous Raytheon hangar.

Lawrence noted that the idea of guided-missile interceptors was once seen as far-fetched, but technology and persistence have made "hitting a bullet with a bullet" a reality.

"The early systems were highly complex for the time," he said, noting that new inventions like radar-operated fuzes were paired with old-style vacuum tubes.

"Before the missile was fired, it had to warm up, which is not a great thing in the heat of battle, but it was the best solution at the time," Lawrence said.

Early versions like the Terrier used radar guidance technology called "beam riding," revolutionary for the time but decreasingly accurate at greater ranges, he said.

In 1956, the advent of semiactive radar guidance - which homes in on signals reflected off a target - greatly increased the accuracy of the early missiles, Lawrence said.

In 1965, the Terrier and Tarter missiles were combined into the Standard Missile-1, the first all-electric, solid-state missile with an advanced motor.

The advancements would influence the course of all future missile development, Lawrence said.

"Enhanced motor propellant, better controls, increased flight time, higher speed and improved autopilots can all be credited to our early 'missileers,' " he said.

More than a dozen allied nations still use the latest version of the SM-1 for fleet defense, and more than 10 use the SM-2.

In 1970, the SM-2 was mated with the Aegis Combat System, then a new naval fire-control system, dramatically improving midcourse guidance, Lawrence said.

Continual improvement has followed, culminating with the latest version, the SM-6, which features advanced, on-board radar that allows it to hit targets beyond the originating ship's sight, he noted.

Earlier this week, Raytheon got the go-ahead from a Pentagon review panel to start full-rate production of the SM-6, with deliveries expected to start by April 2015. Final assembly of the SM-6 takes place at Raytheon's new factory in Huntsville, Ala.

While the SM-6 is expected to protect U.S. warships well into the future, the SM-3 is the cornerstone of the Pentagon's phased-in approach to missile defense in Europe.

The SM-3 Block IA missile, which is deployed by the U.S. and development partner Japan, has nearly a 90 percent success rate in test firings, with more than 130 missiles delivered ahead of schedule, Lawrence said.

"This reliability is vital as you consider the short-range missile threat from nations such as Iran and North Korea," he said.

And despite some early setbacks, the latest SM-3 Block IB version is back on track, Lawrence said.

The Block IB missile, which features an improved, two-color infrared seeker and an advanced system of guidance rockets, failed its first intercept test in 2011.

But the new missile has had three successful intercepts in a row, including a test last week in which the missile hit a separating target.

Lawrence recalled how the gravity of the SM-3's mission sunk in while he nervously awaited results of the latest test off Hawaii.

"The stakes were high, and so were our hopes for an intercept," he said.

"And in those tense moments right before impact, I realized someday it will not be a test - someday, lives will be on the line."

Did you know?

The Standard Missile was produced by General Dynamics in Pomona, Calif., until the mid-1990s.

In 1992, Hughes Aircraft Co. acquired the Standard Missile and five other General Dynamics missile lines and moved production to Tucson, bringing thousands of jobs.

Raytheon Co. acquired the defense businesses of Hughes Electronics, including Tucson's Hughes Missile Systems Co., from General Motors Corp. in 1997.

Contact Assistant Business Editor David Wichner at or 573-4181.