NASA engineers are now ready to resume work on testing the rocket, with a well-defined set of test collectively called green run. Last year, when there was talk of a first launch of the SLS by the end of 2020, the agency had considered the option of give up part of these tests. A hypothesis then discarded: all the stages of the green run have been decreed necessary for the safety of future crews. For this, and for others delays accumulated over the months, the inauguration of the new launch system should slip to second half of 2021. Without prejudice to the goal Moon 2024, which expects a return to our satellite in less than five years. A request that came directly from the Trump administration, which in the last year has prompted NASA to press the accelerator to make the necessary stages for the moon landing, first of all the testing of the Orion capsule and precisely there finalization of the SLS.
While Orion has already successfully tested engines, the tests of green run they are what is missing to make the rocket really operational. As seen in the infographic below, it is one checklist of 8 steps well defined. The only one to have the box already checked is the first: a test at central stadium of the rocket, to which dynamic forces have been applied to verify its flexibility. The result of this test, conducted in January, was fundamental for the evaluation of the correct functioning of the guidance, navigation and control systems of the rocket.
The next 7 tests, which NASA has just given the go ahead, will gradually test theavionics of the rocket, the systems of safety, the mechanisms of propulsion, the control system of the vector of thrust, the operations of countdown, the management of propellant and the functioning of the engines.
The last step is considered the most important: during the so-called test hot fire, the 4 central stadium RS-25 engines will come on for 8 minutes. The deal will produce one thrust equivalent to what the rocket will face during the liftoff – one of the most delicate moments for any throw.
Once you have completed all the stages of the green run, the Space launch system will be considered ready to fly. This will proclaim a green light for Artemis I – the first of a series of increasingly complex missions, which starting from the return on the moon should lead to the first landing on Mars.