NASA SLS test stands

Test Stand 4697 will stand 85 feet tall and is designed to test the liquid oxygen tank of the new rocket NASA is developing in Huntsville. (NASA)

Test Stand 4693, standing 215 feet tall, will have twin towers and be used for testing the liquid hydrogen tank, which will be 185 feet tall when completed. (NASA)

HUNTSVILLE, Alabama – Brasfield & Gorrie construction company of Birmingham has won a $45 million contract to build two large stands at Marshall Space Flight Center to test the fuel tanks and other key hardware for NASA's new Space Launch System.

Engineers will use hydraulic cylinders at each stand to twist, push and bend five separate parts of the rocket’s core stage to make sure they can survive launch pressures.

One of the stands, Test Stand 4693, will be 215 feet tall with twin towers. It will test the SLS liquid hydrogen tank, which will be 185 feet tall itself. The tank will be tested at Marshall with liquid nitrogen inside.

The second stand, Test Stand 4697, is 85 feet tall and designed to test the liquid oxygen tank of the new rocket. "Within the foundation of this stand, we have 1.75 miles of embedded anchor rods - that gives you an idea of the type of stability we need to test these parts with such high-level force," project manager Byron Williams said in a NASA press release.

"These test stands will play a vital role in strengthening America's space exploration capabilities," Brasfield & Gorrie Vice President and Division Manager Alan Anthony said late Tuesday. "We are proud to continue our strong working relationship with the U.S. Army Corps of Engineers and our work at Redstone Arsenal while supporting NASA's Space Launch System."

The two test stands will take about a year to build. Construction is expected to start in late May in Marshall’s historic West Test Area, where one stand will be built atop the bedrock-deep foundation of the stand Wernher von Braun used to test the massive F-1 Saturn V engines.

The core stage of the Space Launch System is 200 feet tall. By comparison, a Saturn V first stage was roughly 75 feet tall. The core is composed of five parts: two fuel tanks, a main engine compartment with associated plumbing for fueling, an intertank ring to join the two tanks and a top ring to attach the core to the Orion upper stage. Breaking the core into five pieces allows NASA to test them on the new stands.

The tanks will be be built at Michoud while the test stands are built at Marshall. All of that will occur this year. The parts will be barged up from New Orleans to Huntsville, where testing will probably begin in 2015 and continue into March or April of 2016. SLS is due to launch in 2017.

Updated at 3:45 to correct the amount of the contract and at 5:44 p.m. to include a statement from Brasfield & Gorrie