It’s not often that Wright-Patterson Air Force Base hosts astronauts testing in its facilities. In fact, it’s been since the 1960s.
But due in part to the relationship between the Air Force and NASA as well as the location and unique capabilities of the Defense Department’s only human-rated centrifuge, 10 astronauts in their royal blue walked through the doors of the Air Force Research Laboratory’s 711th Human Performance Wing at Wright-Patt Nov. 1 to undergo two days of centrifuge testing.
“We are thrilled to have NASA and Boeing astronauts testing in our facilities,” said Brig. Gen. Mark Koeniger, 711 HPW commander. “Our partnership brings the 711th Human Performance Wing’s unique capabilities into the space domain, using our brand-new centrifuge. We designed the system to be agile and rapidly adaptable for any possible customer, and NASA was ecstatic to be our first partner outside the DOD.”
The agility of this new centrifuge rests in its interchangeable cockpits. The AFRL-NASA discussion began in August, which is when engineers from both teams began working to transform the centrifuge, more commonly used for fast-jet pilot training, into a system for astronaut testing.
“We were able to give NASA engineers 3-D models of the gondola in our centrifuge, and then they designed their cockpit displays,” said Scott Fleming, 711 HPW centrifuge program manager.
“We only had to add one shim and shave off an edge of one of the 50 manufactured parts; it was nearly an exact fit,” he said.
For aircrew training, the centrifuge allows students and U.S. Air Force fast-jet aviators the capability to experience up to nine Gs, or nine times the normal force of gravity, to teach the effects of G-forces on human physiology. Also, it allows for the measure of the flyer’s ability to counteract the effects and prevent G-induced loss of consciousness.
“For pilots, the G-forces are felt through the top of the head in the z-axis,” explained Fleming. “But for astronauts, the G-forces are felt mostly in the chest in the x-axis. They have to still be able to reach forward and accomplish certain tasks on their control panels.”
These tasks were part of the testing that each of the 10 astronauts had to accomplish as the centrifuge spun. They also had pre- and post-test questionnaires as well as NASA physicians, who also conducted pre- and post-medical exams to bookend their centrifuge spins.
The astronauts, nine from NASA – one, Boeing, each took a turn, literally and figuratively, and this testing marked the beginning of what could be a new era of space travel.
One of the 10 astronauts testing was Chris Ferguson, a former Navy fighter pilot and former NASA astronaut who flew to space three times and was commander of shuttle Atlantis in 2011, the final shuttle to launch from the United States. Ferguson still wears the royal blue space suit but now for Boeing as the first commercial astronaut. He explained that Boeing was testing in the centrifuge at the invitation of NASA.
“In this new era of commercial space, where you have commercial space companies that are tasked to provide a service, but they may not have that depth of background in physiology – that’s where I think NASA steps in and uses its history and its relationships to make sure that their astronauts, when they use commercial space vehicles, are adequately prepared for what they are going to experience,” Ferguson said.
A long-standing relationship
NASA’s relationship with the Air Force dates back to Project Mercury, the first human spaceflight program in the United States, which spanned from 1958-1963 and included astronauts such as Alan Shepard and John Glenn, among others.
Kevin Rusnak, AFRL senior historian, discussed the history of centrifuges in North America as well as the historical partnership the Air Force and earlier, the Army Air Corps, has had with astronauts and the space program.
“Dr. Harry Armstrong was the first to build a centrifuge back in 1935 for the then Army Air Forces, and as far as we know, he was the first to build one in North America,” explained Rusnak. “He had the shops (at was then Wright Field) construct it to do the first aeromedical testing and is considered the father of aviation medical research.”
A second centrifuge was built and used through World War II, but then a third was constructed at Wright-Patterson and used to test and select astronauts for Project Mercury in the late 1950s, Rusnak explained.
“They ran all the astronauts through the testing right here on base,” he said. “Then based on the tests that were run, the Air Force recommended the seven candidates to be accepted for the Mercury program. Those are the ones we now know as the ‘Mercury Seven’ astronauts.”
A couple more centrifuges followed and have been used for a variety of things from testing the endurance of people to the forces of acceleration to the comfort of pressure suits and space suits, Rusnak said.
“What happens when you’re wearing a 50-pound space suit and you’re going at four Gs and the suit is pressing against your skin? Researchers at the Air Force Research Laboratory and now the 711th Human Performance Wing ask questions and develop solutions. Like – ‘How can that suit be constructed so it’s more comfortable for the astronauts’ and ‘Are they still mobile – can they reach up and flip switches?’” Rusnak said.
These questions apply to Air Force pilots too, he explained. “If you’re flying at a high speed or you have to eject, how can your body sustain the G load and what kind of equipment can AFRL and more broadly, Air Force, provide these pilots to protect them when they’re going at these rates of speed? All this can be tested on our centrifuge.”
Centrifuge testing remains vital
Fast forward to what is the next generation of space travel; centrifuge testing and training still remain crucial to both safety and human performance.
The astronauts who participated in the testing included Ferguson, Bob Behnken, Zena Cardman, Mike Hopkins, Sunita Williams, Eric Boe, Josh Cassada, Victor Glover, Douglas Hurley and Nicole Mann.
NASA astronaut and physician Michael Barrett, who also is a Wright State University alum and worked with AFRL researchers for his master’s thesis, discussed the new space vehicles, the different experience of G-forces in these vehicles in comparison to a high-speed jet, and the importance of readiness.
“We’re starting to fly these new vehicles that are very different from the space shuttles,” said Barrett. “The shuttle had a very gentle G-profile both upward but especially downward. The new commercial space vehicles – the SpaceX Dragon, Boeing Starliner and even the new Orion – we’re back in the family with the Mercury, Gemini and Apollo era where we had much higher G-forces in both ascent and entry.”
Barrett explained that during those [earlier] programs, NASA used centrifuge training both for preparing the astronauts to feel those G loads and to work and learn how to operate under them, but also to inform design and cockpit strategies and operations.
“With the new vehicles back in the family with those G loads, we’re basically reviving that whole G training aspect and every astronaut will start going down this path,” he said. “This is our pathfinder effort – our first time to start spinning people with the G loads of the new vehicles.”
“Who knows where this will lead,” said Ferguson, “but I think it’s a pretty darn good start.”
“AFRL and the 711th Human Performance Wing are always excited to forge and reinforce these unique partnerships,” said Koeniger. “Both Boeing and SpaceX, in cooperation with NASA, understand that the 711HPW holds capabilities in aerospace physiology that can’t be found anywhere else. The historical relationship with NASA from the days of John Glenn will now work to deliver our next generation of astronauts to the International Space Station.”