NASA started a several months-long series of flights on 3 August to identify the physiological impacts of flying in high-performance military aircraft on the human body.

The flights are being conducted at NASA’s Armstrong Flight Research Center at Edwards Air Force Base in California and will take place over 160 flight hours. The tests are managed by the NASA Engineering and Safety Center at Langley Research Center in Virginia.

During the tests researchers will measure the breathing of five NASA pilots flying in F-18A/B and F-15D aircraft, while they use different equipment types and experience different flight conditions. The flight conditions that will be tested include benign environments, typical in instrument proficiency training, to more strenuous environments, such as those found in high altitude, aerobatic manoeuvring and combat manoeuvring, according to NASA.

In recent years, the US Navy and Air Force have been perplexed by an increase in the number of pilots experiencing physiological events during flight across a variety of aircraft. Symptoms from physiological events include cognitive impairment, numbness, tingling, lightheadedness, behavioral changes and fatigue.

Data collected will just serve as a baseline for comparison because NASA’s aircraft still use the legacy technology of a Liquid Oxygen System as opposed to newer military aircraft that utilise an Onboard Oxygen System.