NASA is currently working on a massive rocket called the Space Launch System or SLS. We mentioned last month that the massive rocket was set to undergo some critical tests. The SLS core stage is set for more tests this month and still sits on the B-2 test stand at the Stennis Space Center. The massive rocket is 212 feet tall and is more powerful than any rocket used since the 60s.
The upcoming tests are part of the Green Run intended to sort the rocket of any faults before its first flight scheduled for November 2021. The Green Run is split into eight parts, and the SLS team has been going through the test since the beginning of the year. On test case five, the team performed gimballing on the engines, which is where they are moved around hydraulically to allow course corrections during flight.
There are two remaining core stages, with number seven known as the wet dress rehearsal. That test involves the core stage tanks being filled with liquid hydrogen and liquid oxygen. The rocket holds 500,000 gallons of liquid hydrogen and 200,000 gallons of liquid oxygen. The extremely cold propellants will be piped in from barges to the core stage tanks over 6.5 hours.
Engineers will gather data during the test to compare against mathematical models to determine if the entire system behaves as expected. The team will also simulate a large countdown during the wet dress rehearsal taking the launch up to the 33-second mark before launch. The eighth and final test is called the hot fire test. With the core stage anchored to the stand, the fire test will ignite the four RS-25 engines and fire them together for the first time.
The engines will be fired for a full-duration burn. The engines develop 1.6 million pounds of thrust, and the engine fires into a massive bucket with lots of water to prevent it from melting the metal frame the rocket is attached to. If all goes well, the first test flight will happen next year.