The many complaints that have been expressed by the US aircrew of the F-35 regarding the heat stress in the cockpit raised an obvious concern that, as a result of such heat levels, the aviators' core body temperature may increase significantly, and subsequently cause severe cognitive impairment- risking both the pilot and the mission.

In order to validate this hypothesis, we will measure the aviators' core body temperatures while inside the cockpit of the F-35, to see whether their core body temperatures are rising to a level that can cause heat stress or not. The temperatures will be measured on another fourth generation aircraft as well for comparing purposes.

The temperatures will be measured using a Telemetric pill which will be ingested by each aviator. Once ingested, the pill will transmit the data to an external monitor. The collected data will be examined and analyzed in order to determine the likelihood of heat stress occurrence.

Inclusion Criteria:

• F35 pilots
• Signing on informed consent

Exclusion Criteria:

• Sickness two weeks prior the experiment