This airline allows flight attendants to drink while ‘on duty’ — but only under these circumstances

One major US airline’s flight attendants have the opportunity to fly high.

Attendants at rival airlines have discovered that their counterparts at United Airlines — as well as Air Canada — are occasionally permitted to drink on the job, according to Paddle Your Own Kanoo.

The Chicago-based carrier is now the only major airline in the country to allow this — but there’s a catch.

Passengers don’t need to worry: United flight attendants are not permitted to drink alcohol when they’re actually working a flight or in uniform, but there are a few instances where crew members are able to consume alcohol even when they’re technically on duty.

In the airline industry, there’s something called “deadheading,” which is when flight attendants or pilots travel as passengers while on the clock at the company’s expense for one reason or another.

This could happen because airlines have to get their crew members from their base to another destination or vice versa, so they’ll sit in normal seats like any other passenger.

Additionally, an aircraft change could require more or fewer crew members, or crew members might fall ill which requires replacement crew dispatches. The seasonal start or end of a particular flight could also lead to this, meaning the “deadheading” crew wouldn’t have a plane to actually work on.

Sometimes, however, flight attendants fly as a passenger for a couple hours and then immediately get on another flight as a flight attendant. In this case, there wouldn’t be an excuse to consume any alcohol.

It may seem reasonable to allow flight attendants to be treated like other passengers on the plane when they’re deadheading as their last work duty of the day — but out of all the major airlines, United is the only one that allows their flight attendants to drink when they are deadheading and not expected to work in the same day.

The Post has reached out to United for comment.

Of course, there are rules for the eccentric perk for United flight attendants. They cannot be in uniform, and the plane door must be shut with everything ready for takeoff before they take their first sip just in case something happens and they unexpectedly need to work on that flight.

Around the world, attendants are allowed to drink alcohol while deadheading with the same rules as United — but American airlines are less likely to offer this perk, mainly because they operate large domestic networks and flight attendants are often reassigned at the last minute.

If flight attendants are drinking while deadheading, airlines lose the capacity to assign them to another flight at a moment’s notice.