CNN interview Mark Jefferies

A 3 minute interview with Mark flying the Abarth Extra 300L and the Extra 330SC. What you don’t see is James Williams from CNN in the front seat of the 300L, after the flight he was not so chirpy and needed 30 mins sitting to recover !  G forces in excess of 4.5 will induce G-LOC ,  g-induced Loss Of Consciousness (abbreviated G-LOC), a situation when g-forces move the blood away from the brain to the extent that consciousness is lost. As g-forces increases, visual effects include loss of colour vision (grey-out), followed by tunnel vision (where peripheral vision is lost, retaining only the centre vision). If g-forces increase further, complete loss of vision will occur, while consciousness remains. These effects are due to a reduction of blood flow to the eyes before blood flow to the brain is lost, because the extra pressure within the eye (intraocular pressure) counters the blood pressure. The reverse effect is experienced in advanced aerobatic maneuvers under negative g-forces, where excess blood moves towards the brain and eyes red out.  Mark and other top aerobatic competition pilots do AGSM and can take up to 10G without a anti-G suit as the military use in addition to AGSM techniques.  Link here for the video.