SLS Green Run Wet Dress Rehearsal

Engineers demonstrated loading, controlling and draining more than 700,000 gallons (2.6 million liters) of cryogenic propellants into the liquid oxygen and liquid hydrogen tanks and then returning the stage to a safe condition. Toward the end of the simulated terminal countdown, the test automatically stopped due to a valve closure being off by a fraction of a second. The team has corrected the timing, and additional analysis clears the way for hot fire.