Stamina, endurance and strength
To be able to withstand the immense physical strain that this creates, the pilots must be fighting fit. A combination of stamina, endurance and overall physical strength is a winning formula for ultimate control in the cockpit as aviation surgeon Dr Thomas Drekonja explains.
"The parts of the body that really need to be trained to withstand the G forces are the muscles of the lower legs, abdomen and also the arms to have complete control of the raceplane with fine movements despite the weight that is induced by the high G forces," he says.
Of the 14 Master Class pilots competing in the world's fastest motorsport series, all are in top physical condition and have the experience and resilience to remain in control while racing. The main challenge for anyone experiencing positive G is to keep the blood flowing to the brain and head – which is forced to the lower limbs.
"If the Gs are high, you have a pooling of the blood as this leaves the upper portion of the body, especially from the brain and the head," confirms the expert medic. "The first signs of G are the narrowing of the field of vision and then you'll start to lose the periphery, colour and sight. You'll start to 'grey out' and over time can even lose consciousness.
"This is a very serious issue, but long before it gets to that point, a pilot would lose their field of vision and colour perception. These well-trained pilots, well adapted to deal with Gs, would never get to this point. A normal individual could maybe sustain up to 5Gs, whereas a trained pilot can resist substantial G force. There have been individuals who have resisted up to 20G for a very short period of time."
Dr Drekonja advises specific training to help the pilots utilise their bodies in the battle against G forces, with emphasis on muscle control to stop the blood leaving the head.
"The kind of training that the pilots need to do to sustain high G over time is to train their muscles. They will need to do muscle strengthening exercises and they need to be up on overall physical fitness just to be ahead of the game," he continues. "It's a hard job out there in the raceplanes and you want to be as fit as possible to sustain those high Gs. From one pilot to another it varies, but our pilots have a limit of 10G out there. Our guys are very fit and can fly at this level of G for a long time."
As in any intense sport, the pulse rate will go up during the competition – and the tension, excitement and G loads are all part of competing in this unique high level sport. Another key factor to assist in G resistance is getting the breathing right – and this can be seen from the onboard footage of the pilots when flying the track as they appear to 'grunt' while inhaling and exhaling.
"There are special breathing techniques that are used by the pilots and checked by us, where the pilot really stresses their abdominal muscles and breathes very heavily into those to increase the pressure rate while also increasing the oxygenation of the blood," confirms Dr Drekonja. "We've got a wonderful group of pilots and they all have one thing in common – they're fit as a fiddle. They know what they're doing and are well trained for high Gs. They are the best of the best."