A closed-loop control system to help pilots of high-performance aircraft avoid g-induced loss of consciousness (G-LOC) incidents has been proposed by Israel's Center for Aerospace Medicine Research.
One of the most serious threats to aircrew flying highly manoeuvrable fighters, G-LOC was blamed for the loss of one of South Korea's brand-new Boeing F-15Ks last year. And a survey of UK Royal Air Force aircrew last year found more than 20% had experience at least one G-LOC incident.
The main cause is a failure to maintain cerebral perfusion pressure - the pressure of bloodflow to the brain - during high-g manoeuvres. The centre, based at the Fisher Institute for Air and Space Strategic Studies in Herzliya, has designed a coin-sized wireless sensor that can be embedded into the pilot's helmet to monitor his vital signs. The system alerts the pilot just before he reaches the "no return point" for G-LOC, says centre head Eran Schenker.
At the same time, the proposed closed-loop control system would increase the oxygen supply to the pilot and alert other crew on board or in nearby airspace, as well as ground controllers. It would also disconnect the flight controls from the pilot's stick and initiate an automatic recovery to bring the aircraft back to normal flight. In most cases the pilot will recover in less than 60s after the aircraft stabilises.
The US Navy, meanwhile, is studying the potential of functional near-infrared spectroscopy (fNIRS) as the basis of a hypoxia and G-LOC warning system, under its Cognitive Cockpit research programme. By passing infrared light through the skull and measuring its absorption at different wavelengths, fNIRS can measure the volume and oxygenation of blood in the pilot's brain.
Source: Flight International
