Israeli defense electronics firm Elbit Systems says it has developed a body sensor that could help save the lives of pilots by forewarning of possible loss of consciousness in extreme manoeuvres or because of oxygen starvation. 

Named "Canary", the system is initially geared for the military market and fighter pilots who experience extreme physiological stress during sharp turns, high-speed acceleration or possible oxygen starvation at high altitude. But it may be adapted for civil aviation use as well.

Loss of consciousness because of high G-forces that prevent blood getting to the brain, known as G-LOC, is a regular concern for fast-jet pilots. Hypoxia can affect anybody flying at high altitude and can also lead to incapacitation.

Both phenomena have caused crashes and deaths over many years, said Yaron Kranz, a senior research and development director at Elbit, which developed the sensor together with Israeli start-up LifeBEAM.

Systems that can take over an out of control plane have already been developed by aircraft and auto-pilot manufacturers, but Elbit's system is different in that it senses the condition of the pilot rather than the aircraft.

"The system detects the physiological state of the pilot while he is still in control and it can predict if he is going to lose consciousness, giving enough time to take evasive action," said Kranz, a former fighter pilot.

Two well-documented examples of hypoxia were the Helios Airways disaster in 2005, in which 121 people died when their airliner came down near Athens, and the 1999 business jet crash of top golfer Payne Stewart in the mid-Western United States.

Canary, which includes a button-sized sensor and related computer, is contained within the pilot's helmet.

The system will only flash an alert on the helmet's visor if it senses an imminent threat. If it detects the pilot has passed out, it will tell the plane's mission computer to take control to avert disaster, Kranz said.

To detect hypoxia in civilian aircraft, the sensor could be adapted to be worn without a helmet.

Elbit Systems, whose drones and surveillance devices are top sellers worldwide, is Israel's largest listed defense company.

Together with Rockwell Collins, it is developing the pilot helmet, expected to be ready for production within a year, for Lockheed Martin Corp's advanced F-35 fighter.