How is the air up there?

POOR air quality on passenger jet flight decks may impair pilots’ flying performance and handling of emergencies, a study has found.

Flight simulator tests showed that as carbon dioxide levels were raised, pilots found it more difficult to carry out tricky manoeuvres. Their ability to handle unexpected emergencies, such as an engine failure on takeoff, was also affected.

‘‘Our results suggest that we need to know more about how air quality on the flight deck can be used to enhance pilot performance,’’ investigator Piers MacNaughton, from the Harvard TH Chan School of Public Health in the US, said.

Thirty commercial airline pilots were recruited for the study, which involved teams of two taking three hourlong flights in an Airbus A320 simulator.

Pilots flew for 90 minutes at a time while carrying out 21 manoeuvres of varying levels of difficulty without the aid of an autopilot.

The challenges included executing a steep turn bank, maintaining a constant altitude while circling, stall recovery, collision avoidance and coping with engine failure during takeoff and landing.

During each flight the concentration of CO2 was randomly set at 700, 1500, or 2500 parts per million (ppm) of air.

Pilots were 69% more likely to pass a manoeuvre test when CO levels were 700ppm than they were with 2500ppm.

The negative effects became more pronounced the longer pilots were in the simulator.

Available data on CO2 levels on commercial aircraft flight decks is limited. Previous studies have indicated they are less than 800ppm. However, they have been measured as high as 2000ppm and even higher in the cabin, depending on the aircraft type and other factors, the researchers, writing in the Journal of Exposure Science & Environmental Epidemiology,

said.

They said current standards for air quality on flight decks might be inadequate. — PA