The anti-gravity suit, or G-suit, doesn’t help pilots at Luke Air Force Base by reversing gravity; it helps them withstand the acceleration forces put on their bodies while maneuvering in the F-16.
A new G-suit, known as the full coverage anti-G-suit, which is the same one used by pilots in the F-22 and the F-35, has arrived on the scene.
The G-suit currently being used by many F-16 pilots at Luke has been around a long time.
“The current, or legacy, G-suit was designed in the ‘40s,” said Maj. Sean Sarsfield, 56th Training Squadron aerospace physiology director. “There has been little change since then. Pilots were using a 70-year-old suit in aircraft designed 20 years later.”
With the next generation of aircraft arriving soon, the G-suit was updated. The difference between the two is that the new FCAGS has air bladder coverage over 90 percent of the lower body, whereas the legacy suit had coverage around 30 percent, Sarsfield said.
“The legacy G-suit has inflatable bladders on the calf, thigh and abdomen,” said Tech Sgt. Timothy Lacey, 56th Operations Support Squadron survival equipment craftsman. “When a pilot pulls Gs in an aircraft, the bladders fill up with air to help keep blood in their upper body.”
The pressure created by the bladders filling with air squeezes the legs to stop the blood from being pulled down into the legs by the force. These bladders along with muscle straining techniques keep pilot’s blood in the head to keep the pilot from passing out.
“This new full coverage suit is just what the name implies,” Lacey said. “Instead of the five bladders there is one large bladder throughout the whole suit. This way more of the legs get pressure, helping the pilot retain blood in the upper body.”
The new suit and those before were designed to help pilots from G-induced loss of consciousness.
“G-induced loss of consciousness has killed dozens of pilots over the years, the last at Luke being in 2008,” Sarsfield said. “Flying up to nine Gs in the F-16 pushes a pilot’s body to its physiological limits in maintaining sufficient blood pressure at eye level. The anti-G straining maneuver has always been a pilot’s number one defense against GLOC, offering them three to four Gs of protection, while the legacy suit provided only about 1.5 Gs of protection. The new FCAGS provides an additional one to 1.5 Gs of protection beyond that. This improves the safety margin significantly. The huge benefit is that pilots now have an increased margin of safety when pulling extreme Gs. Additionally, it allows them to better employ the aircraft while under high G because they don’t have to devote as much attention to a maximal AGSM.”
Pilots in the F-16 with the FCAGS can now withstand Gs longer and better than with the legacy suit.
The FCAGS was originally made for the new generation aircraft and have to be remade for F-16 pilots.
“They had to reverse engineer the suit for the F-16,” Lacey said. “The connecter hose, where the suit connects to the jet to fill with air, had to receive a new fitting to make the connection, but more important it had to be moved from the right side to the left.”
The new suit also takes longer to be fitted and to put on.
“Because the suit is all one bladder they had to make it in 11 different sizes,” Lacey said. “So a pilot will get a size closest to their leg size, then they tighten strings that run the length of the legs to get a customized fit for each pilot. The fitting takes longer because they need to be stepped into like pants. The time it takes to keep the pilots safe is worth it.”
Luke received an initial shipment of 130 new G-suits and continues to get shipments monthly.
“We are getting all the student pilots fitted for the new suit,” Lacey said. “But it’s hard because many of the pilots wear the same size suit, so we have to keep ordering sizes. We hope all Luke pilots will have them soon.”
The new student pilots will never know what it was like to fly with the legacy suit; but for three pilots at Luke, they have had the chance to fly with both.
“I’ve flown with it three times over the last couple weeks,” Sarsfield said. “It’s definitely better and noticeably provides more of a lower body squeeze. However, for me, I still must use the classic AGSM technique in the seven-G and above range. It doesn’t eliminate the need to execute a nearly normal AGSM while above seven Gs. I have talked to others who have flown with it, and they have reported better, more dramatic benefits. There will be individual differences based on physiological differences in tolerance to Gs.”