Engineers Test NASA's Space Launch System Booster Forward Skirt to the Limits

A critical connection between NASA's new rocket and its twin solid rocket boosters that will help it get to space proved it could withstand millions of pounds of launch stress during a series of ground tests that ended May 20. The booster forward skirt, which houses the electronics responsible for igniting, steering, and jettisoning the two five-segment boosters and carries most of the forces acting on the boosters during launch, is one of two places at the top and bottom of the booster where it is attached by struts to the Space Launch System (SLS) core stage. The core stage will store cryogenic liquid hydrogen and liquid oxygen that will feed the vehicle's RS-25 engines. When completed, SLS will be capable of taking a crew and cargo on deep space missions, including to an asteroid and eventually Mars.

Transcript

00:00:00 Music At the beginning of SLS program we identified a concern using heritage hardware. One of the key areas of that concern was the forward skirt. So the part we're testing is the forward skirt of the solid rocket boosters that we used on shuttle successfully for over thirty years. That skirt was tested to 1.4 times its flight predicted loads. That flight

00:00:32 load with its margin was essentially the same load we’ve got for SLS. Due to trying to use this skirt with the fairly high loads on this we’re venturing into an area of very nonlinear behavior. So it’s very difficult to come up with a redesign and it's very difficult to predict analytically without a test like this. The thrust post must carry the lift off

00:01:02 load as it would be in flight. We’re also required to have margins beyond that to ensure this forward skirt can carry the loads. So we’re doing the test at ATK in Promontory Utah. We're using one of the old static motor test stands. We’ve got a force ring that weighs about twenty eight thousand pounds; we're hanging it on the skirt. We attach four one million pound

00:01:25 load rams. Each load ram then applies up to one million pounds of force measured through load cells that we will use to determine the capability of the skirt. We're gonna start the first phase where we will kind of check out loads up, make sure all the systems are working up to a million pounds of axial load and make sure that’s working. And that will be followed by a basic

00:01:49 limit load lift off test. Then we will take the test up to 110% of load. Then we will disassemble certain areas and inspect the hardware then reassemble, run it up to failure of the article or the limit of the test stand. So for me, one of the exciting portions about the test is that we used to fly these on shuttle, we go pull them out of the water, refurb

00:02:23 the skirts and then get them ready for flight again. So this is one of the skirts that we pulled out of the water and now we are going to do a test to determine just what capability that skirt has in order to determine if it's got acceptable margins to fly for SLS.