Withstanding the high-G
Like military pilots, Red Bull Air Race contenders experience mind-boggling G-forces; yet unlike those highly skilled jet pilots, expert Air Racing stars do not wear compression G-suits. The two former fighter pilots who took first and second place in the 2018 World Championship explain how they withstand forces up to 12 times their body weight.
In the roughly 60 seconds that it takes to complete a run through a Red Bull Air Race track, pilots’ bodies are constantly stretching and compressing as they experience the G-forces that come with hard banking and vertical turning manoeuvres. And it is fast – with the pilots going to 10G in as little as 0.03 seconds.
“It’s tough, I can tell you,” says 2018 World Champion Martin Sonka, who flew the supersonic JAS-39 Gripen and the L-159 ALCA in the Czech Air Force. “Of course it’s very physically difficult because the body is stressed by all the Gs, and then in this racing environment you have to control the aeroplane with one-millimetre precision. The body has to be strong, because otherwise the forces cause it to move, which causes your arm on the controls to move, which results in movements of the whole aeroplane.”
“That’s something people don't realise,” agrees Matt Hall, a former Wing Commander and Fighter Pilot of the Year in the Royal Australian Air Force, who finished second overall at November’s season finale. “When I take people for a fly and demonstrate what it’s like in a racetrack, they hang on with both arms locked tight, whereas I’ve got to have a very soft and precise hand while I’m pulling huge G or rolling rapidly left and right. You need to develop a rock-solid body, but your right arm needs to be super relaxed.” Sonka adds, “A run through the track is like a workout with weights in the gym – with the first lift you’re strong, but with the 10th or 12th, you’re getting weaker. We have to keep fit to have the same strength and power from the first manoeuvre through the very last.”
Dr. Thomas Drekonja, who heads the medical team for the Red Bull Air Race, explains that there is even more to the fitness of these athletes. “The flying sessions are short, but there are many sessions in a single day, and that requires stamina,” he points out. “And the flying is happening in a tiny little composite aircraft in the sun, the weather, the elements. It can be cold or extremely hot – something like 50 degrees [Celsius] once the canopies are closed.”
Flying at high-G not only puts about 900kg of force on a pilot like Hall – who weighs in at 75kg in his gear – but it can also cause blood to pool in the lower extremities of the body, which is why fighter pilots wear G-suits to stay alert. The Red Bull Air Race examined the possibilities of racing with liquid-membrane G-suits (as opposed to the inflatable models that are coupled with a fighter jet). But the high Gs experienced by the Air Racing pilots, while intense, are so brief that a pilot would be back out of a manoeuvre before the suit could take full effect.
“In a turning engagement in a fighter, you could be under very high-G for up to 60 seconds,” Hall describes. “When racing, we’re under more G – up to 12, whereas in a Hornet it’s 7.5 and in an Eagle it’s 9 – but for us it’s very short duration.”
Instead of wearing G-suits, the pilots provide the needed compression on their arteries by tensing the muscles in their arms, legs and abdomen, something that becomes reflexive. While flying is their favourite way to stay G-fit, they all follow physical training programmes outside the cockpit, and they typically wear physical monitors to compare their body’s performance in the air and on the ground.
“I actually love every sport, but I had to reduce work in the gym, because bigger muscles are more weight,” Sonka reveals. “I compensate by more aerobic training – running, cycling, swimming. Last year I was in the pool more or less every day, and this year I’m focused on using my own body as resistance, really concentrating on my core muscles.”
Hall, meanwhile, reveals one of the “asymmetric core” exercises that he finds effective: “I stand on one leg, reach forward and pick up a weight down in front of me, then reach forward again and put it back. This makes sure we’re engaged, but that we’re always able to be flexible and precise while we are engaged.”
Fans watching the Red Bull Air Race live broadcasts might catch a glimpse of Hall giving his right hand a shake just before entering the racetrack. It is just another way he makes sure his hand and arm movements remain fluid even when the rest of his body is taut.
While Sonka and Hall aim for peak physical condition primarily to deliver the best results in the racetrack, Dr. Drekonja emphasises that for him and the rest of the Red Bull Air Race organisation, there is an even more important reason for assuring optimal physical fitness. “This motorsport requires a lot of technical skills, and athleticism can enhance that,” he states. “But the driving force behind all we’re doing on the medical side – like inviting the pilots for physical fitness and stamina assessments at the Red Bull High Performance Center – is not just to produce faster competitors, but because we want a set of extremely safe pilots who can undergo the strains and the demands of the sport and perform to a level where they’re always safe for everyone involved.”