NASA’s new lunar mega-rocket will return to the shop to undergo minor repairs that may lead to its launch being delayed to late summer or later.
That means NASA has, for now, given up on completing what it calls a wet rundown of the rocket — a detailed countdown test, described as “wet” because it includes loading more than 700,000 gallons of ultra-cold liquid hydrogen and oxygen. liquid in the machine’s propellant tanks.
The rocket, called the Space Launch System, spent the last 30 days on the launch pad of the Kennedy Space Station in Florida, undergoing tests of ground systems. The experiments would culminate with the wet dress rehearsal.
But three attempts to conduct this trial ended ahead of schedule due to a number of minor technical issues that occurred during the countdowns. The purpose of testing a new rocket system is precisely to identify and solve problems such as these.
Technicians also discovered that an upper stage valve was malfunctioning, and on the third attempt to perform the dress rehearsal last Thursday, it was modified so that only the launch stage booster tanks would be filled.
However, a hydrogen leak was detected in the so-called rear umbilical mast attached to the bottom of the rocket, and the test was cancelled. The oxygen tank wasn’t even half full, and the hydrogen supply had just started.
Last week, NASA officials said they hoped to fix the hydrogen leak while the rocket was still on the launch pad. But on Monday they said they had changed their minds. Next week, the rocket is due to be taken back to the Vehicle Assembly Building, where technicians can have easier access to parts of the ship. This will make it possible to replace the faulty upper stage valve.
At the same time, a company that supplies nitrogen gas, used to eliminate hazardous gases, will upgrade the systems. Problems in the nitrogen supply delayed the countdown on two of the attempts to perform the dress rehearsal.
“The lunar megarocket is doing really well,” Tom Whitmeyer, deputy associate administrator for developing common exploration systems at NASA, told a news conference on Monday. “I think we’re getting really smart with this rocket. But we still have a little more work to do.”
The Space Launch System, a key component of NASA’s Artemis program to send astronauts back to the Moon, is years behind schedule and has already exceeded its budget by billions of dollars. With the current problems, Whitmeyer said, it would be difficult to get the rocket ready in time to launch during a two-week window in early June. There are other 15-day windows of opportunity starting in late June and late July.
“We’re working on two different schedule options that we’ll be reviewing with the management team over the course of the week,” said release director Charlie Blackwell-Thompson.
One option would be to carry out the bare minimum of repairs — the upper stage valve and the hydrogen leak — and get the rocket back to the launch pad in the shortest possible time to do the wet dress rehearsal. A second option would involve some additional work needed to prepare the rocket for launch. Both options require one more trip to the Vehicle Assembly Building.
A third option would be to fully prepare the rocket for launch and then conduct both the dress rehearsal and launch without returning to the assembly building.
Translation by Clara Allain.
