Thomas Cook was left red-faced after its newly rebranded Cook’s Club planes turned out to have one fatal flaw.

The sleek aircraft, which have “I heart Cook’s Club” emblazoned on the side, look great – until the middle door opens.

The way the letters are positioned means the message then reads: “I heart Cock’s Club”, an unfortunate gaffe that the internet was quick to pick up on.

Facebook group A Fly Guy’s Cabin Crew Lounge posted a picture of the faux pas on Wednesday 3 October, and it was quickly shared far and wide.

“Someone’s made a right cock up with this new Thomas Cook paint job. Do you want to join the ‘I heart cocks club’?” wrote Dan Freedom on Twitter.

An airline spokesman said: “It goes without saying it is unintended, but it is one way to highlight where the emergency exit is.”

Cook’s Club is the tour operator’s latest offering to tempt millennial holidaymakers back to the package holiday.

The youth brand offers hotels in Crete and Gambia, with vegan food, cocktails created by a Berlin-based mixologist, and activities including escape rooms, silent discos, VR games and a Rage Room – where guests can let off steam by smashing bottles and vases with a wide range of tools.

It’s the second time in recent months that an airline has made a high-profile spelling blunder.

Hong-Kong based carrier Cathay Pacific unveiled a new plane in September, only for people to point out that something was not quite right with its livery.

The key “F” in the name was missing, leaving the aircraft branded as “Cathay Paciic”.

The errant aircraft has since gone back to the shop for a touch-up. Cathay Pacific tweeted: “Oops this special livery won’t last long! She’s going back to the shop!”