By John Barker, Mobile District, public affairs specialist
Work is finishing on two rocket test stands, built for NASA by the U.S. Army Corps of Engineers, Mobile District, which will someday help send astronauts to Mars. The stands, located at NASA’s Marshall Space Flight Center in Huntsville, Ala., will test rocket propellant tanks for NASA’s Space Launch System rocket.
“Currently NASA is outfitting the stands with special test equipment that will be necessary to capture the test results once the fuel tank is completed,” said Curtney Walters, Mobile District project engineer for two of the test stands, numbered 4693 and 4697.
The Corps began construction on Test Stand 4693 in May 2014 and on Test Stand 4697 in September 2016. The $68.8 million project was completed in December. NASA expects to begin using the test stands in spring of next year.
“As far as anyone here can remember, the Corps hasn’t participated in a project like this, at least since the 50s or 60s,” said Walters.
NASA’s Phil Hendrix, Marshall facilities construction project manager for both test stands, recognized the Corps’ role in what will be a historic project.
“NASA’s ability to contract the construction of Test Stand 4693 and 4697 through the U.S. Army Corps of Engineers provided an excellent mechanism to achieve our goals,” said Hendrix. “The Corps put together a great team of architecture, engineering and construction firms who were able to deliver two unique structures that will be used to test the core-stage fuel tanks for the Space Launch System (SLS) rocket.
“This SLS will be the most powerful rocket in history and the launch vehicle that will send astronauts in NASA's Orion spacecraft beyond low-Earth orbit into the solar system on missions around the moon and eventually to Mars,” he said. “These stands are necessary to accommodate the sheer size of the core-stage components and the extreme loads we are putting on them – some up to 9 million pounds.”
NASA is currently building the Orion spacecraft and SLS rocket. The rocket’s liquid hydrogen and liquid oxygen tanks for the massive launch vehicle’s Core Stage will be tested on the Corps-constructed stands. Test Stand 4693 created a new skyline for Marshall, with its dual towers reaching 221 feet high. Standing nearby is Test Stand 4697, at 70 feet.
SLS will be propelled off the Launchpad at Kennedy Space Center in Florida by four RS-25 engines powered by liquid hydrogen and liquid oxygen fuel, flanked by two five-segment solid rocket boosters. All together, the rocket’s 8.4 million pounds of thrust will launch the SLS from the launch pad around the moon, to deep space and ultimately to Mars.
Although the first flight atop the SLS will not have humans aboard, it paves the way for future missions with astronauts. Ultimately, it will help NASA prepare for missions to the Red Planet. The tank will be subject to tremendous forces during launch and flights to deep space.
“The forces the tank will experience in the test stand are as close as you can get on Earth to what the tank will experience on its way to space,” said Scott Chartier, a test engineer in Marshall's propulsion systems test branch. “During the series of tests, the tank will endure up to 9 million pounds of compressive, up-and-down loads, and up to 300,000 pounds of shear or 'twist' loads.
“We haven’t seen this magnitude of testing since we tested the Saturn rockets and the space shuttle,” Chartier said. “These test facilities will serve NASA well as we continue on the journey to Mars. I can’t wait to take my kids to an SLS launch and see the hardware we helped develop on these test stands -- sturdy stands even their generation can use as they continue exploring space.”
In addition to the SLS tank, NASA reports that the new Marshall test stands can be used for a variety of vehicles and testing needs, including commercial rockets or other large spacecraft structures needed for deep space exploration.
Jennifer Stanfield, public affairs officer at NASA Marshall Space Flight Center, contributed reporting to this article.