The COVID-19 pandemic has required people to take new measures to mitigate the spread of the communicable virus. Guidelines from health organizations, government offices, and universities have been disseminated. Adherence to these guidelines cannot be more critical for flight training. This study explored the effects face masks had on CO2, heart rate, respiration rate, and oxygen saturation while wearing a face mask at an oxygen level simulated to 5,000 feet. Thirty-two instructor pilots (IP) volunteered to participate in the study. IPs spent 90 minutes in a normobaric chamber while wearing a cloth face mask or a paper face mask. Participants were measured before entering the chamber, at the 15-minute mark, at the 45-minute mark, at the 90-minute mark, and after exiting the chamber where they briefly removed their mask for a final measurement. No differences were found between type of face mask. Wearing face masks did not present any potential health or safety issues for the IPs. However, IPs did report moderate dislikes (e.g., comfort, issues with fatigue, restriction of movement) of wearing face masks. Although face masks may be a nuisance, it does not appear to create any health or safety issues at a simulated altitude of 5,000 feet.