Engineers Begin Testing Elements for Orion Service Module

The Orion crew module adapter structural test article
The Orion crew module adapter structural test article is hoisted at NASA’s Plum Brook Station in Sandusky, Ohio. Credit: NASA

Engineers at NASA’s Plum Brook Station in Sandusky, Ohio, began the first of a series of modal tests on a structural representation of the crew module adapter (CMA) for Orion. The CMA will connect the capsule to the ESA (European Space Agency)-provided service module for the spacecraft’s next mission, Exploration Mission-1. The service module is designed to be the powerhouse that fuels and propels Orion in space.

The tests at Plum Brook Station shake structural elements at various frequencies to simulate how launch vibrations and acoustics will affect the spacecraft during its trip to space atop NASA’s Space Launch System rocket. They are being conducted ahead of the arrival of a structural representation of the ESA service module to the facility this fall for additional testing.

Engineers are using a “building block” approach to testing in which they evaluate each piece as the elements composing the service module are stacked atop each other to validate it before flight hardware begins arriving in 2017.

Space Launch System Hits Engine Milestones for Missions with Orion

Test of the RS-25 Rocket Engine
Engineers at the agency’s Stennis Space Center near Bay St. Louis, Mississippi, conducted a successful 450-second test of the RS-25 rocket engine May 28.

NASA’s Space Launch System (SLS), which will launch Orion on missions to deep space destinations like an asteroid and on toward Mars marked important steps this week to prepare for journeys beyond Earth orbit.

Engineers at the agency’s Stennis Space Center near Bay St. Louis, Mississippi, conducted a successful 450-second test of the RS-25 rocket engine May 28. The hotfire test was conducted on the historic A-1 Test Stand where Apollo Program rocket stages and Space Shuttle Program main engines also were tested. RS-25 engines tested on the stand will power the core stage of NASA’s new rocket with Orion atop it.

One of the objectives being evaluated in this test is the new engine controller, or “brain.” The RS-25 is unique among many engines in that it automatically runs through its cycles and programs. The controller monitors the engine conditions and communicates the performance needs. The performance specifications, such as what percentage of thrust is needed and when, are programmed into the controller before the engines are fired. For example, if the engine is required to cycle up to 90 percent thrust, the controller monitors the fuel mixture ratio and regulates the thrust accordingly. It is essential that the controller communicates clearly with the engine; the SLS will be bigger than previous rockets and fly unprecedented missions, and its engines will have to perform in new ways.

Engine maker Aerojet Rocketdyne also completed RS-25 Engine 2063 at Stennis, after approximately three months of work. The new engine becomes the 16th assembled RS-25 flight engine in inventory for SLS flights. The engine will be one of four RS-25s used to power Exploration Mission 2, the second SLS launch with Orion targeted for the 2021 time frame. Testing of these four engines will begin later this year as work accelerates on NASA’s newest launch vehicle. Four previously-flown RS-25s will be attached to the first SLS core stage and test fired together as a stage before being approved for the first SLS launch planned for 2018, the first integrated mission with Orion. Check out more, including a timelapse video of the assembly here.