Posted on 26 Oct 2018 by Nadjejda
Hot-firing the engines
Controlled but still explosive firing tests of Orion’s propulsion system are taking place at NASA’s White Test Sands Facility in New Mexico, USA. Recent footage shows the mighty thrust of the spacecraft’s main engine, which provides enough power to lift a van.
The engine must be tested and qualified on Earth before it is considered fit to fly. The video shows the engine being put through its paces in a combination of tests from five to 20 seconds. This engine, the so-called OMS-E, is a refurbishment from the Shuttle programme that last flew in 2011 on the Space Shuttle Atlantis.
“The exhaust gases from the engine are channeled through a water-cooled tube, which we call the diffuser, and then released into the atmosphere. This protects the bench and the engine itself from the exhaust plume,” explains ESA’s propulsion lead for Orion, Thierry Kachler.
The ‘hot-firing’ tests are done with the Propulsion Qualification Model for Orion’s European Service Module propulsion system. The module will not fly into space, but the hardware needs to be tested to the extremes found outside our atmosphere.
A total of 33 engines of 3 types will provide thrust to ESA’s service module to navigate and orient the spacecraft in all directions.
This is not the first time the engines have been fired up. During an initial series of tests in 2017, some of the engines showed a deviation in their performance. “Since they are designed to work in vacuum, this was a direct consequence of testing them in our atmosphere,” says Thierry.
The problem was readily identified, and over the past year the team both investigated the issue and found a fix to ensure the engines work properly in an open-air environment. “It took some time but we are confident this will work now,” adds Thierry.
More tests to come
There are 12 ‘hot-firing’ tests planned this year to qualify the propulsion of the European Service Module. The next six months will be dedicated to integrating the new hardware and software and running more ‘hot-firing’ tests, up until early 2019.
This test campaign involves teams from Airbus, ESA, NASA (Glenn Research Center, White Sands Test Facility) and Lockheed Martin.