By Chris Skeldon 
Trevor Mahleman
After three attempts to complete a critical supply test of the Space Launch System rocket, NASA decided to take a break.
space agency saturday night Announce plans The large SLS rocket launches from the launch pad at the Kennedy Space Center to the Vehicle Assembly Building in the next few days. This is a major setback for the program, which since April 1 has tried to complete a “pilot” test, during which the missile is refueled and operational within 10 seconds of launch.
The decision comes after three attempts in the past two weeks. Each attempt to refuel was thwarted by one or more technical problems with the missile, moving launch tower, or ground systems providing the fuel and gases. During the last attempt, Thursday, April 14, NASA successfully loaded 49% of the initial stage liquid oxygen fuel tank and 5% of the liquid hydrogen tank.
While this is a step forward, it did not include the most dynamic part of the test, with the rocket being fully propelled and pressurized; Earth and computer systems are put into the final countdown when each variable is closely monitored. NASA had hoped to complete this test run to find out the kinks of the complex launch system so that when the rocket is launched later this year for the actual launch, the countdown will reasonably continue.
NASA said its contractors, as well as its agency, will use the next few weeks to solve problems that arose during refueling tests when the SLS rocket returns to the large vehicle assembly building. For example, Air Liquide, a nitrogen gas system supplier, will upgrade its capabilities. NASA will also replace a faulty check valve on the rocket’s upper stage, as well as fix a leak in the “secret service tail mast” of the portable launch tower, the 10-meter-high structure that provides the rocket’s engine and electrical lines to block. .
The space agency’s announcement did not provide any information on the schedule’s effects. Apparently it will take about a week to prepare the SLS missile and return it to the Vehicle Assembly Building. Rocket work at this location will likely take at least most of May.
NASA will then have to make some tough decisions. You can choose to roll the rocket and the moving launch tower on the platform a second time and try to complete the wet test exercise. Then, following normal procedure, NASA will propel the rocket into its assembly building to arm the flight safety system, before it rolls a third time to the launch pad for takeoff. It appears that the closest possible launch of the SLS in such a scenario will be in August, but it is most likely to be launched in the fall.
Another option that NASA could pursue is to start testing and completing the diving suits on the platform, then go ahead and launch them in a few days if that works. In this scenario, NASA could launch the SLS rocket in June or July. However, this can be risky due to the flight safety system.
During a conference call on Friday, Artemis launch director Charlie Blackwell-Thompson confirmed there was a 20-day deadline once the flight safety system was armed. (This is a range safety mechanism used by all orbital missiles that destroy the booster if it goes off course.) Once the system is activated, it will take about a week to make final preparations at the Vehicle Assembly Building and a week to move to the launch pad and make preparations there. That would leave just a week to test re-supply, recycle merchandise, and possibly try a shot or two before the 20-day window closes.
In other words, this means that the wet-robe test must be virtually defect-free and then the casting attempt must also be defect-free. It could also mean that Florida’s summer weather—when there are plenty of storms and other extreme conditions—needs cooperation.
Finally, NASA engineers must balance a number of other factors, such as wear and tear on the rocket, ribs installed on the exposed side on the outside, as well as seemingly endless life considerations with the hardware. For example, agency officials closely monitor the state of the fuel in solid rocket boosters, which have been stacked for 16 months, among other things.
However, NASA appears confident that it will survive this painful reversal of the SLS: a program now 11 years old, in which NASA has invested more than $30 billion in rockets and ground-based systems being tested.
“I have no doubts that we will finish this test campaign, listen to the hardware, and the data will take us to the next step,” Blackwell Thompson said Friday. We will take appropriate measures and launch this vehicle. I don’t know what exactly that date is, but I have no doubts that we will finish our test drive and be ready to fly.”