A second Hot-Fire test gives the agency a chance to conduct three special gimbaling experiments that weren’t completed in the first attempt.

A second Hot-Fire test gives the agency a chance to conduct three special gimbaling experiments that werent completed in the first attempt.
NASA has announced the decision to redo the Green Run Hot-Fire test of the agencys Space Launch System (SLS) Core Stage at the Stennis Space Center in Mississippi.
The Core Stage was fired for 67 seconds on January 16 in the B-2 Test Stand at Stennis before the test was ended early. NASA said three days later that the hydraulic system on Engine 2 hit intentionally conservative limits, triggering a shutdown by the flight computer.
A second Hot-Fire test gives the agency a chance to conduct three special gimbaling experiments that werent completed in the first attempt, which would gather data on the interaction and interdependence between the four RS-25 engines and the stages mechanical systems.
In a statement, NASA said: After evaluating data from the first hot fire and the prior seven Green Run tests, NASA and core stage lead contractor Boeing determined that a second, longer hot fire test should be conducted and would pose minimal risk to the Artemis I core stage while providing valuable data to help certify the core stage for flight.
For the upcoming test, engineers will be updating conservative control logic parameters that resulted in the flight computer ending the first hot-fire test earlier than planned.
A second Hot-Fire test was tentatively set for as early as the fourth week in February. The upcoming test will last approximately at least 4 minutes, although the goal remains to perform a full-duration test.