A steel beam is "flown" by crane into position on the 221-foot-tall (67.4 meters) twin towers of Test Stand 4693 during "topping out" ceremonies April 12 at NASA's Marshall Space Flight Center in Huntsville, Alabama. When construction is completed later this year, dozens of hydraulic cylinders at the stand will push and pull on the giant liquid hydrogen tank of NASA's Space Launch System, subjecting it to the same stresses and loads it will endure during liftoff and flight. SLS will be the world's most powerful rocket for human space exploration, able to take astronauts in the Orion spacecraft on deep-space missions, including our journey to Mars. Topping out is a builders' rite traditionally held when the last beam is placed on top of a structure during building. Before being welded into place, this beam was signed by members of the Marshall Center Operations, SLS and other teams involved in the test stand's design and construction, including the U.S. Army Corps of Engineers; general contractor Brasfield & Gorrie; architects Goodwin Mills and Cawood; architects Merrick & Company; NAFCO Fabrication; and LPR Construction. The same group of government and contractor teams recently topped out Test Stand 4697 at Marshall, where similar tests will be conducted on the SLS liquid oxygen tank.
Image credit: NASA/MSFC