The One Direction hunk reportedly shocked fellow passengers when he became annoyed at airline staff during the flight from Puerto Rico to Philadelphia over the weekend.
According to the Daily Mirror newspaper, the 20-year-old singer became angry after being told there was a four-hour delay because he was eager to see his girlfriend Sophia Smith, who celebrated her 20th birthday yesterday (09.02.14).
A source said: "Liam was livid. He was tired and grumpy, and just wanted to get home because it was his girlfriend's birthday. He snapped at officials and started swearing. Everyone was quite taken aback."
But the star started to calm down when he realised he wasn't the only passenger annoyed that the US Airways flight 770 was grounded at 1.30pm.
The source added: "He apologised soon after. He didn't mean any offence."
However, fan Brooklyn Wiles was not impressed by Liam's outburst and claimed he refused to smile when she asked for a photograph after the drama.
She posted on Twitter: "I love One Direction ... but for him to act like a complete jerk because of a flight that was delayed due to a bomb threat?!?
"Every single person on that plane has to deal with this too... we all are trying to find flights and get home. And he was swearing up a storm. He was a nobody three years ago...
"Just because you're famous doesn't mean you should be a jerk to your fans.
"It's hard to love someone who takes fame too far. Liam Payne, I've lost my respect. (sic)"
The flight finally took off at 5.18pm after a passenger made the bomb threat and police found no explosives on the plane.