The largest rocket element NASA has ever built, the core stage of NASA’s Space Launch System (SLS) rocket, manage to successfully fire its four RS-25 engines for 8 minutes and 19 seconds. The test took place on 18 March at NASA’s Stennis Space Center.
The successful test, known as a hot fire, is a critical milestone ahead of the agency’s Artemis I mission, which will send an uncrewed Orion spacecraft on a test flight around the Moon and back to Earth, paving the way for future Artemis missions with astronauts.
“The SLS is the most powerful rocket NASA has ever built, and during today’s test, the core stage of the rocket generated more than 1.6 million pounds of thrust within seven seconds. The SLS is an incredible feat of engineering and the only rocket capable of powering America’s next-generation missions that will place the first woman and the next man on the Moon,” said acting NASA Administrator Steve Jurczyk.
This is not the first time the SLS has conducted a hot fire test. NASA previously conducted a hot fire test of the SLS core stage on Jan. 16. The four RS-25 engines fired together for the first time for about one minute before the test ended earlier than planned. Following data analysis, NASA determined a second, longer hot fire test would provide valuable data to help verify the core stage design for flight while posing minimal risk to the Artemis I core stage.
During the second hot fire test, the stage fired the engines for a little more than eight minutes, just like it will during every Artemis launch to the Moon. The longer duration hot fire tested a variety of operational conditions, including moving the four engines in specific patterns to direct thrust and powering the engines up to 109% power, throttling down and back up, as they will during flight.
The two propellant tanks in the SLS core stage collectively hold more than 733,000 gallons of supercold liquid hydrogen and liquid oxygen to help fuel the RS-25 engines at the bottom of the stage. The core stage has a complex network of flight software and avionics systems designed to help fly, track, and steer the rocket during launch and flight.
Next, the core stage for SLS will be refurbished, then shipped to NASA’s Kennedy Space Center in Florida. There, the core stage will be assembled with the solid rocket boosters and other parts of the rocket and NASA’s Orion spacecraft on the mobile launcher inside the Vehicle Assembly Building at Kennedy in preparation for Artemis I.
Take a look at the hot fire test below:
🚀 Today, the @NASA_SLS core stage that will power our @NASAArtemis I mission to the Moon successfully completed its Green Run hot fire test. If data looks good, its next stop is @NASAKennedy to be assembled with the other rocket elements. Here’s a recap: https://t.co/QpYSIQq4ox pic.twitter.com/aLmEkS9pbA
— NASA (@NASA) March 18, 2021
Picture: NASA/Robert Markowitz