WASHINGTON — NASA is moving ahead with the next Artemis 1 launch attempt on Nov. 16 after finding no major repairs required to the Space Launch System and Orion from Hurricane Nicole.
In a call with reporters Nov. 11, Jim Free, NASA associate administrator for exploration systems development, said technicians were working on minor issues caused by the storm’s passage a day earlier but nothing that could not be repaired in time for the current projected launch date of Nov. 16 during a two-hour window that opens at 1:04 a.m. Eastern.
“Right now, there’s nothing preventing us from getting to the 16th,” he said. “We do have some work to do.”
That work, he said, includes cutting away some loose caulk, known as RTV, on the Orion launch abort system that isn’t needed for flight. A rain cover in one SLS engine was torn and is being fixed, while water that pooled in the crew access arm was removed. An umbilical leading from the launch tower to Orion came off a tray and was replaced.
He added that a tail service mast unit that feeds liquid hydrogen into the SLS had an electrical umbilical that had “some erratic signals,” that was being inspected. That wiring harness could be replaced if required.
Free spent much of the call explaining, and defending, the agency’s decision to leave the SLS on the pad. He said there was a lengthy discussion about the forecast before deciding to roll out to the pad Nov. 4. “There were folks really thinking it hard” about rolling out, he recalled. “In the end, everyone agreed that we should roll out.”
By the time forecasts showed the storm had strengthened, it was too late to roll back to the Vehicle Assembly Building (VAB). In discussions Nov. 6, he said, the earliest the vehicle could roll back was late Nov. 8. “The wind speeds then were predicted to be 35 knots [65 km/h] sustained gusting up to 40 [74 km/h],” he said, raising concerns about loads on the vehicle as it moved back to the VAB. “With the risk of moving with the high winds we decided to stay at the pad.”
The winds ultimately stayed just below the certification limits for the SLS. At the 18-meter level, NASA reported a peak just of 132 kilometers per hour, just below the rated limit of 137 kilometers per hour.
Free said NASA also measured the winds at other levels of the pad, including the top of the lightning towers, 140 meters high. “During the hurricane, all the measurements taken showed no breaking of those limits,” he said.
Free declined to give the wind limits at other levels of the vehicle, citing concerns associated with the International Traffic in Arms Regulations (ITAR), one category of export controls. “It’s how we do the calculations and on the design of the vehicle,” he argued. “You can bring some of that together and draw some conclusions that would violate that.”
However, NASA has previously published wind limits for the SLS, notably in an October 2021 document available on a NASA website with a notice that it is “approved for public release; distribution is unlimited.” That shows wind limits increasing with height at the pad, topping out at the 150-meter level at 172 kilometers per hour. The top wind gust reported during the storm was approximately 160 kilometers per hour at an altitude of 142 meters
The wind limits, he added, were conservative. “It’s 75% of what we can take, which means we have another 25% of margin on top of that before we even get into our 1.4 factor of safety,” he said. “From our perspective, we stayed within our certification at the wind that we saw during the hurricane.”
He acknowledged that NASA likely would have kept the SLS in the VAB had it known before the Nov. 4 rollout how Hurricane Nicole would develop. “If we knew on the night before we were rolling out that it was going to be a hurricane, we probably would have stayed in the VAB.”
Keeping the vehicle on the pad, though, preserves the Nov. 16 launch attempt as well as a backup date on Nov. 19. Free said NASA had also secured an additional launch date of Nov. 25, the last one available in the current launch period, from the Federal Aviation Administration.
He said that he was not nervous about having SLS on the pad during the storm, at least not more than he does in general about the vehicle ahead of its first launch. “I worry about this rocket if it were bright and sunny all the time because this is our first one, and our flight test has absolutely critical objectives that are going to be difficult to achieve,” he said. “So, I’m going to worry about this rocket until we see that [Orion] capsule safely back in the well deck of the Navy ship.”