Nasa

Nasa has begun building a mockup of a core stage of its new rocket Space Launch System (SLS), which will be used in future deep-space missions in three Alabama communities in the US.

Measuring 213ft and weighing 230,000lb, the steel simulation of the core stage will store cryogenic liquid hydrogen and liquid oxygen that will power the rocket’s RS-25 engines.

The flight hardware of the core stage is currently being made at Nasa’s Michoud Assembly Facility in New Orleans, US.

Designed by engineers at Nasa’s Marshall Space Flight Center in Huntsville, Alabama, US, the mockup will confirm core stage operations and transportation, which include routes for testing, assembly and launch.

Marshall Space Flight Center core stage pathfinder project engineering lead Shane Carpenter said: "This hardware is an excellent proving ground for the core stage, from manufacturing and assembly to the launch site.

"We do not want the first time we transport the core stage to be with flight hardware.

"That is why having a pathfinder is critical to the programme."

The inexpensive, core stage mockup, without engines or avionics, will be built at Dynetics’ facility in Huntsville and G&G Steel in Russellville, Alabama, US.

Nasa recently selected Radiance Technologies to build, assemble and transport the pathfinder vehicle, with delivery to Nasa scheduled in early 2017.

"Measuring 213ft and weighing 230,000lb, the steel simulation of the core stage will store cryogenic liquid hydrogen and liquid oxygen that will power the rocket’s RS-25 engines."

Marshall Space Flight Center stages pathfinder project lead David Adcock said: "We look forward to working with these companies on such an important project for SLS.

"We want to ensure that the form and fit of the entire process for the core stage is successful and any issues are addressed, before the flight hardware leaves Michoud.

"It helps reduce risk and keeps us on schedule."

After receiving the pathfinder at its Michoud Assembly Facility, Nasa will ship it to the agency’s Stennis Space Center, Mississippi, US and place it vertically in a test stand. Testing is expected to be performed in 2017.

Following completion of the test, the pathfinder will be shipped to Nasa’s Kennedy Space Center in Florida, US.

Nasa, in both Mississippi and Florida sites, will use the pathfinder to ensure all modifications of the vehicle meets SLS core stage specifications.

The Block I configuration of SLS will have at least 70t lift capacity and will be powered by twin boosters and four RS-25 engines. The next upgrade of SLS, Block 1B, will have 105t lift capacity.

SLS’s Block II will include a pair of advanced solid or liquid propellant boosters to provide a 130t lift capability.

Nasa, during the first of SLS, expects to send 13 CubeSats to test innovative concepts along with an uncrewed Orion spacecraft in 2018.

Image: An artist’s concept of the core stage pathfinder. Photo: courtesy of Nasa / MSFC.