Airline reveals important reason why you never see pilots with beards on duty

If you've ever caught a flight, there are a number of things that you may have noticed while travelling by plane.

Air travel has a number of quirks and features for a whole variety of different reasons.

You may have wondered about the procedure in certain scenarios, such as if a passenger dies on the flight.

There are also things like the small holes in the plane windows, unnerving at first but actually a deliberate design feature.

Of course, rules and regulations for flight crews will have some variation for each company, but there are certain safety protocols which the majority airlines have to follow.

And among them, a little surprisingly, is a rule that pilots do not have full beards.

A spokesperson for American Airlines told Thrillist: "We do not allow pilots with facial hair to be on active duty."

But why?

Have you ever wondered why you never see pilots with beards on duty? (Juan Silva /Getty)

Well, it turns out that it's not just a fashion statement, it could be a matter of life and death.

The American Airlines spokesperson continued: "It's actually safety driven. Safety is one of the biggest, most important things in our industry."

You are probably familiar, though hopefully not too familiar, with the emergency procedures on planes where oxygen masks will drop from the ceiling in an emergency in which the cabin depressurizes.

The problem is that a full beard can prevent the mask from fitting properly.

If you're a passenger then you can manually hold it in place, though if your beard prevents it fitting properly this could still be a huge problem.

A 1987 safety review explained: "Bearded passengers might expect some deficit in oxygenation following a decompression that could lead to varying degrees of hypoxia (physiological conditions that result when the body does not receive enough oxygen)."

There's a very good reason for the rule. (Richard Sharrocks / Getty)

It added: "The deficit in oxygenation might not be severe enough to be life-threatening, but could cause loss of consciousness."

Needless to say being conscious is quite helpful when flying a plane.

The safety review took a look at pilots and judged if their performance was impacted by having a beard, and it was.

It said: "Three popular TSO-approved crewmember oxygen masks equipped with mask-mounted regulators were tested to determine if a decrement in performance would occur as a result of the presence of facial hair."

The study continued: "The data resulting from these tests indicated that decrement in performance does occur when facial hair is present along the sealing surface of crew oxygen masks.

"This decrement is proportional to the amount of facial hair present, the type mask worn, the suspension system associated with the mask, and the exercise level to which the individual is subjected."

That seems pretty conclusive!