Artemis 1: leaks fixed, new critical test coming soon
NASA announced that its engineers have replaced two of the failed seals that led to hydrogen leaks on the Space Launch System, the NASA launch vehicle that was scheduled to blast off on Aug. 29 for the first of three Artemis program missions.
The launch has already been postponed twice. Each time, the cause was a malfunction in a hydrogen line. During its investigations, the agency finally traced the problem to two circular joints that were not perfectly sealed.
NASA did not say whether it was an assembly problem, or whether the parts had been damaged at some other time. However, it announced today that these two elements had been replaced without any problem on September 9. In theory, the leaks should finally be plugged.
A new filling test on September 17
Now, it will be necessary to make sure that these interventions have indeed sealed the leaks. NASA will conduct a new filling test of its huge 98-meter high rocket, capable of carrying more than 3 million liters of hydrogen and liquid oxygen. This demonstration will allow engineers to verify the integrity of the new seals under nearly identical conditions to those of the launch.
This test is scheduled for September 17. If the SLS passes this stage, the technical teams will finally be able to tackle a test that leaks have made impossible until now. The objective will be to cool the engines of the spacecraft to a temperature of about -250°C. This will allow to condition the structure to prepare the arrival of the fuel, also kept at an extremely low temperature.
If these tests go as planned, the engineers will finally be able to check off this very important box on their roadmap. But they won't be out of the woods yet.
The US Space Force still has to deliberate
At last count, the agency was still waiting for a response from the US Space Force (USSF). NASA sent a request to extend the certification of the Flight Termination System (FTS). It is an emergency system which must pulverize the spacecraft in the air in case of catastrophic accident. The objective is to avoid that it does not cause big damages by crashing on Earth.
It must be tested regularly (every 25 days), otherwise the vehicle is simply not allowed to take off. But this certification is about to expire. And it turns out that the test procedure is quite long; if it had to go through it again, NASA would be forced to sacrifice several interesting launch windows. The agency is therefore still waiting for the USSF's verdict. It will be decisive when it comes to choosing the next launch date.
We'll see you on September 17 to see if the SLS pipe will finally be watertight. By then, NASA may know more about extending the certification of the FTS. If all the stars align, the agency could consider a launch on September 23 or 27, as its officials recently suggested. If not, we will have to wait until October to see the SLS launch to the Moon.
