Missile test planned Wednesday morning

A Minuteman 3 missile is set to blast out of its underground silo early Wednesday at Vandenberg Air Force Base, a long-scheduled routine test that now comes as North Korea is flexing its military might.

The test is targeting takeoff at 1:01 a.m. Wednesday, but the window remains open for six hours to accommodate any potential postponements because of unfavorable weather or technical problems.

After blastoff, the Air Force will track the weapon's mock warhead as its travels more than 4,200 miles to targets in the Kwajalein Missile Range in the central Pacific Ocean.

Although it comes amid heightened tensions - as North Korea sends off a flurry of missiles and rejects calls to quit - this test has been listed for July 2006 on Vandenberg's launch lineup as far back as 2004.

The U.S. military regularly tests unarmed Minuteman missiles to collect data on their accuracy and reliability.

Equipped with three solid-propellant rocket motors, Minuteman missiles stand some 60 feet tall and can travel more than 6,000 miles, reaching a speed of approximately 15,000 mph at burnout.

Some 500 of the missiles are on alert on bases in North Dakota, Wyoming and Montana.

Although it's an older weapon system, the military has undertaken a program to extend the Minuteman's life. Plans include replacing the aging guidance system, remanufacturing the solid-propellant rocket motors, replacing standby power systems, repairing launch facilities, and installing communications, command and control equipment.

July 18, 2006