Elbit Systems is developing new applications for smart helmets that will be able to sense when pilots develop life-threatening conditions in flight. The helmet is fitted with a unique sensor that monitors pilot health by measuring physiological life signs –heart rate, blood flow (perfusion) and oxygen saturation level (SpO2). These signals can indicate developing conditions that could lead to hypoxia or G-induced loss of consciousness (G-LOC).

“These two conditions are life-threatening, since they often cannot be sensed by the pilot,” Yaron Kranz, senior director for business development and R&D at Elbit Systems, told ShowNews. Hypoxia can develop slowly, dropping oxygen concentration in the blood without clear signs that would enable the pilot to take preventive measures. Measuring consciousness is even harder, as G-LOC happens suddenly and without warning.

“The best way to monitor oxygen level is to measure its saturation in the blood, similar to the measurement done on patients. But to do that, you need a different sensor,” Kranz explained. So, Elbit adapted a commercial sensor developed by LifeBeam, an Israeli startup company that devised it to monitor peak performance for extreme sports such as marathon running and mountain climbing. The sensor measures oxygen concentration in the blood, heartbeat and blood perfusion (volume of blood that flow trough to the tissues).

“We are currently in the second phase and expect to complete development in less than a year,” Kranz added. “We embedded the sensor in our new-generation helmets that have integral processing capability.” The helmets were tested in a centrifuge under high loads (9G) with the pilots wearing G-suits. Test pilots flew with them under loads of up to 6G. “The test results we collected so far have shown the sensors performed predictably, reliably monitoring the pilot’s condition, collecting data in flight and providing sound physiological data that will be able to support further decisions and advanced applications in the future,” says Kranz.

Hypoxia can develop in different conditions, he notes. When flying helicopters over high mountain ranges, for example, it can develop slowly over an hour. But when caused by oxygen supply failures, blood oxygen levels can drop in seconds from 90 to 70-60%. G-LOC also occurs abruptly, as pilots are subjected to excessive loads without the recommended preparation. Usually a pilot would recover from G-LOC in 20 seconds, but meanwhile the aircraft is uncontrolled and could hit the ground. A warning issued just prior to the onset of such a condition could alert the pilot to take precautions, breath properly, apply pressure to reduce the load or ease the turn to reduce G. The sensor can profile each individual pilot, and assess his or her performance and tolerance on a specific flight.

Once the system decides that the pilot is in danger, it triggers an audible warning to take action. In case the system “feels” that the pilot is unconscious an autopilot can be activated to take control.

Having such sensors with smart helmets provides the necessary capability to assess the pilot’s condition and consciousness, since the head of an unconscious pilot would “drift” to direction of flight and not move around, look into a turn or watch the instruments or HUD, as a conscious pilot would. Therefore, when the helmet “feels” that the pilot is not behaving normally, along with relevant physiological signs, it could be a good indication that the he or she is not in control.

Elbit Systems plans to introduce the new capability with the Targo advanced helmet, as well as a standalone application for helicopters and transport aircraft. This capability will also find applications in commercial aviation, monitoring crews’ condition and control, as hypoxia and other pilot-induced states have taken their toll in the past.