Elements of the project included a new 650-ton launch table, renovation & modifications to the 325-foot mobile service tower (MST), 270-foot tall mobile assembly shelter (MAS), and the 200-foot tall fixed umbilical tower (FUT). Clark renovated three existing structural steel towers that service the Delta IV vehicle on the pad during pre-launch operations. The MST features, new moveable-multi-level access platforms and a new 50-foot tall addition on the roof to house the new 50-ton overhead crane. The FUT doubles in size, and has a new 180-foot tall lightening tower on top of the structure and two 90-foot long cryogenic fueling swing arms. Clark also constructed one of the first utilized fixed pad erector to be built in the United States. The erector is a bridge deck that is 165-foot in length and weighs 186-tons, a component that elevates the vehicle from its horizontal to vertical position in lieu of stacking the rocket sections in place.
Clark and Thompson Metal Fabricators of Vancouver spent ten months building a 77 x 48 x 24-foot, 650-ton hollow, cathedral shaped structure off-site and outfitted it with a pre-assembled cryogenic utility skid made by Industrial Construction of Idaho Falls, Idaho. This structural steel monolith supports the Delta rocket on the launch pad and provides critical blast protection while supplying delicate fuel piping and electrical controls for liftoff. Vacuum jacketed piping and quick disconnect umbilical systems on the launch table supply super-cold liquid hydrogen (-430û F) and liquid oxygen (-360û F) fuel to the rocket.
Navigating one thousand nautical miles, Bragg Crane and Rigging transported the launch table by barge from Thompson Metal Fabricators’ facility on the Columbia River near Portland, Ore. Once the launch table was offloaded at Vanderberg’s SLC-6 wharf, it was then moved two miles over a winding road by way of a multi-wheeled transporter up to the oceanside launch pad.
Boeing chose a new horizontal processing method for the Delta IV, where the rocket is assembled and tested in a special onsite processing facility in a horizontal position and then taken to the pad and lifted to a vertical position for launch. Previously conventional rocket assembly and pre-launch testing has been done on the launch pad itself in a vertical position. The Delta IV horizontal processing allows multiple rockets to be prepared for launch simultaneously and is much more efficient. This pre-assembly and testing process saves money by reducing the length of time the Delta IV needs to be on the pad to about 10 days - 20 days less than previous rocket launches for Boeing. The SLC-6 retrofit comes from the Air Force’s Evolved Expendable Launch Vehicle program, where aerospace companies are encouraged to develop more powerful rockets and support systems that are so efficient they slash launch costs by 25%.
Activation and validation phases will continue until the Delta IV launch from California, which is scheduled for Fall 2003. Boeing is managing the complex.
Funded during President Lyndon Johnson’s administration, SLC-6 has a rich history. For the last 40 years, the programs at Vandenberg Air Force Base have had historic impact on the future of American space exploration. Two of the nation’s most ambitious programs also began here - the Manned Orbiting Laboratory and the U.S. Air Force version of the Space Shuttle. In the 1990’s, commercial firms began launching rockets from the base. Now the Air Force Space Command’s largest base, Vandenberg covers 98,000 acres and provides work for more than 18,500 people.