If you’re travelling during the busy holiday period, it feels like flight delays are inevitable.

But next time you find yourself sitting at a crowded airport gate waiting for a late flight, think twice before blaming the airline.

Because, according to a pilot, the number one cause of delayed flights is actually the passengers.

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Rob Donnelly, a pilot for Republic Airways, told People that his biggest pet peeve as a pilot is also something that affects every single passenger on the plane.

And that’s when people get up to go to the bathroom before the flight has taken off.

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”We’re up in the front trying to get clearance to push back to start getting things going,” he said. “But whenever a passenger gets up to use the bathroom, we are not supposed to move the plane.”

According to Rob, the whole plane must then stop, set the parking brake and wait until the passenger is safely seated again.

He says it’s even worse when the flight is already slightly delayed, and they’re waiting on the tarmac for the signal to go ahead and take off. 

“Now we’ve pissed off the ground controller… who’s trying to push back a hundred other planes and make this chaos work somehow,” he said.

“If we’re sitting there for 30 minutes and somebody tries to get up and go use the bathroom, and then air traffic control finally calls our name to start moving along, we have to tell them we can’t move,” he continues.

“They’re going to be so mad. And then now we just went from the top to the very bottom of the list of priorities.”

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Pilot Rob’s number one piece of advice for travel – especially in the holidays? “Don’t go to the bathroom until you’re up in the air.”

Also, he notes that if you do ever find yourself facing delays, don’t take it out on the airport staff – they really can’t do anything about it.

“It’s just funny in the airport, seeing all the passengers who are just so mad about the flight being delayed and blaming us or blaming the gate agents,” he added.

Another great tip to note is that if you think you’ll arrive in your destination more than a few hours late, it’s a good idea to give your hotel a heads up.

9Travel writer Sarah got a rude shock when she arrived to her hotel in Arizona after midnight, thanks to a missed flight connection, only to find that her room had been given to someone else. The hotel assumed she wasn’t coming, and cancelled her booking.

“So next time you’re delayed, make sure to message, email, or call your hotel to let them know your plans have changed,” she writes.

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