Alaska Airlines Flight 448 took off from Seattle-Tacoma International Airport on Monday afternoon – but the pilot almost immediately reported unusual banging noises coming from the hold on the Los Angeles-bound flight.

The aircraft – with 170 passengers, six crew and one unwitting stowaway on board – returned to Seattle as the pilot told air traffic control: “There could be a person in there so we’re going to come back round.”

The source of the banging turned out to be an experienced Menzies Aviation baggage handler who had nodded off among piles of luggage as he approached the end of his seven-and-a-half hour shift.

Passengers also heard the noises as soon as the plane took off. “All of a sudden we heard this pounding underneath the plane and we thought there was something wrong with the landing gear,” said Robert Higgins, talking to KABC.

Jamie Davis said: “We started hearing yelling, screams for help, very, very faint. That’s when we notified the flight attendant that there was somebody underneath us.”

Another passenger, Troi Ge, said a federal air marshal had also sprung into action. “He started banging back, and he yelled really loud and said: ‘We’re getting ready to land, hold on to something.'”

The airline said later that the embarrassed employee had never been in danger as he was in a pressurised and temperature-controlled environment for the duration of his unscheduled 14-minute journey. He was taken to hospital as a precaution but was later discharged.