Engineers took another step forward in preparations for the first test flight of NASA's new Orion spacecraft, in December. The three primary core elements of the United Launch Alliance (ULA) Delta IV Heavy rocket recently were integrated, forming the first stage of the launch vehicle that will send Orion far from Earth to allow NASA to evaluate the spacecraft's performance in space.

The three Delta IV Common Booster Cores were attached in ULA's Horizontal Integration Facility (HIF), at Cape Canaveral Air Force Station in Florida. The HIF building is located at Space Launch Complex 37 where the mission will lift off.

The first booster was attached to the center rocket in June with the second one was attached in early August.

"The day-to-day processing is performed by ULA," said Merri Anne Stowe of NASA's Fleet Systems Integration Branch of the Launch Services Program (LSP). "NASA's role is to keep a watchful eye on everything and be there to help if any issues come up."

Stowe explained that during major testing experts from NASA's Launch Services Program monitor the work on consoles in Hanger AE at Cape Canaveral Air Force Station. Hangar AE is home to the Kennedy Space Center's upgraded Launch Vehicle Data Center. The facility allows engineers to monitor voice, data, telemetry and video systems that support expendable launch vehicle missions. NASA's Florida spaceport is also where Orion was built and is being processed.

The Delta IV rocket stages were assembled at the ULA plant in Decatur, Alabama, about 20 miles west of Huntsville. After completion, the rocket components were shipped down the Tennessee River and Tombigbee Waterway, a canal, to the Gulf of Mexico.

From there they traveled to Cape Canaveral, arriving on May 6. The elements of the rocket's first stage were then transported to the HIF for preflight processing.

"After the three core stages went through their initial inspections and processing, the struts were attached, connecting the booster stages with the center core," Stowe said. "All of this takes place horizontally."

The three common booster cores are 134 feet in length and 17 feet in diameter. Each has an RS-68 engine that uses liquid hydrogen and liquid oxygen propellant producing 656,000 pounds of thrust. All totaled, the three Delta IV boosters collectively generate 1.96 million pounds of thrust.

The second stage of the Delta IV rocket is 45 feet in length and 17 feet in diameter. It uses one RL10-B-2 engine, also burning liquid hydrogen and liquid oxygen propellant creating 25,000 pounds of thrust.

"The second stage was taken to the Delta Operations Center for processing after it arrived," said Stowe. "The second stage was moved to the HIF on Aug. 29 and is scheduled to be horizontally mated to the first stage on Sept. 12."

The same upper stage will be used on the block 1 version of NASA's new heavy-lift rocket, the Space Launch System (SLS). More powerful than any rocket ever built, SLS will be capable of sending humans aboard Orion to deep-space destinations such as an asteroid and Mars.

"The hardware for Exploration Flight Test-1 is coming together well," Stowe said. "We haven't had to deal with any serious problems. All of the advance planning appears to be paying off."

Once all the launch vehicle stages are mated and thoroughly checked out, the next step is the Test Readiness Review.

"These meetings are held to bring together all the interested parties to be sure the Delta IV rocket is ready for the move to the launch pad where the Orion spacecraft will be mated," Stowe said.

The upcoming flight test will use the Delta IV Heavy to launch the Orion and send it 3,600 miles in altitude beyond the Earth's surface. During the two-orbit, four-hour mission, engineers will evaluate the systems critical to crew safety, the launch abort system, the heat shield and the parachute system. The data gathered during the mission will influence design decisions and validate existing computer models. The flight also will reduce overall mission risks and costs for later Orion flights.

The capsule will re-enter Earth's atmosphere at speeds approaching 20,000 mph, generating temperatures as high as 4,000 degrees Fahrenheit, before splashing down in the Pacific Ocean.

The Lockheed Martin-built Orion is designed to take humans farther than ever before. The spacecraft will serve as the exploration vehicle that will carry astronauts to space and provide safe re-entry from deep-space missions. Orion currently is undergoing final assembly in Kennedy's Neil Armstrong Operations and Checkout Building.

Stowe is especially invested in a successful outcome for the flight test.

"What I'm looking forward to most," she said, "is seeing that Orion capsule being retrieved from the Pacific."