DECATUR, Ala. — As United Launch Alliance (ULA) prepares for a busy launch calendar in 2015 and 2016, the company’s main rocket assembly facility here is operating at the highest capacity in its 15-year history, ULA officials said.

A total of 26 rockets are in various stages of assembly at the plant, which began life in 1997 as a production facility for the Boeing-designed Delta 4 launcher. The Lockheed Martin-designed Atlas 5 was added after 2006, when the two aerospace giants merged their government launch businesses to create ULA.

With 140,000 square meters of floor space, the plant was sized to crank out up to 40 Delta 4 rocket cores per year, a requirement that was based in large part on projections of robust commercial demand for satellite launches. But the commercial market collapsed, a development that ultimately forced Boeing and Lockheed Martin, once bitter rivals in the launch business, into each other’s arms. With the addition of the Atlas 5, the factory’s output averages about a dozen vehicles per year.

SpaceNews visited the Decatur plant Oct. 22, the first time a print media outlet has toured the building in at least three years.

The occasion was the annual shipment of Russian-built RD-180 engines used to power the Atlas 5’s main stage. The four engines, supplied by the U.S.-Russian RD-Amross joint venture, arrived at the Huntsville International Airport, about a half-hour drive from Decatur, on a Russian cargo plane from Moscow.

Within hours of the engines’ arrival the Decatur plant, a completed Atlas 5 that will be used to launch NASA’s Tracking and Data Relay Satellite-L satellite left the factory for its journey by ship to Cape Canaveral Air Force Station, Fla. The launch is scheduled for January 2014.

“This is probably the busiest we’ve been,” said Steve Crow, ULA’s senior manager for factory support. He was the plant’s 32nd employee when he started in 1998.

Today the plant employs more than 800 people, including about 200 who have been hired because of increased work in recent years. About half of those employees are classified as “touch labor,” meaning they work directly on the rockets. The other half are support.

In addition, about 35 government employees oversee operations, including two from the Air Force and others from the Defense Contract Management Agency, NASA and the Aerospace Corp., the not-for-profit center that provides engineering support for U.S. national security space programs.

ULA has consolidated much of the assembly that its legacy companies previously performed in Denver, San Diego and Pueblo, Colo., at Decatur. ULA, which is headquartered near Denver, also has fewer than 200 people working at a plant in Harlingen, Texas, that fabricates and builds unpressurized structures, including payload fairings and adapters.

The current mix of rockets in production at the plant, so large that many employees use electric carts or bicycles to get around, includes 13 Atlas 5 rockets, nine Delta 4s and four Delta 2s. The Delta 2 is no longer in production, but ULA recently sold four of the five remaining vehicles to NASA, and these are now being readied for their missions.

The process of building a rocket typically takes about one year from start to finish. They begin as oversized sheets of aluminum that are cut, cleaned, deburred, shaped through thousands of repetitions of pounding, pressure tested, insulated and assembled.

Engines typically arrive at least one year ahead of launch, company officials said. ULA currently has 2.5 years worth of Atlas 5 engine inventory on hand.

Broc Cote, ULA’s RD-180 program manager, said the company expects to take delivery of five RD-180 engines next year and six in 2015. The Delta 4 uses a U.S.-built main engine dubbed the RS-68.

Although the Atlas 5 and Delta 4 have similar upper-stage engines — both use variants of Aerojet Rocketdyne’s RL-10 — they are completely different designs. ULA is nevertheless working to introduce greater commonality to the Atlas 5 and Delta 4 production process to reduce costs.

Today, about 50 percent of the company’s assembly procedures are common to both vehicles, Crow said. But ULA is under pressure to do more to bring down Evolved Expendable Launch Vehicle program costs, which have skyrocketed in recent years, prompting the Air Force to take steps to bring competition to the national security market.

As part of its cost-cutting strategy, the Air Force is negotiating a block buy of 36 rocket cores from ULA on a sole-source basis. At the same time, however, the service is planning to competitively order an additional 14 missions, giving upstarts like Space Exploration Technologies Corp., commonly known as SpaceX, a chance to break into a market that ULA has had largely to itself since its formation.

ULA, which already uses the same launch teams for Atlas 5 and Delta 4, is looking for ways to bring even more commonality to the manufacturing process, Crow said. Those ideas are regularly vetted by an engineering review board and must also prove they can save the company money, he said.

The U.S. government is expected to spend some $44 billion on satellite launches and related services over the next five years, according to the U.S. Government Accountability Office.

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