A “hyper-aggressive” passenger caused the only Australia-UK flight to turn around and return to Perth, triggering wide-ranging and expensive disruption.

Qantas flight QF9 to Heathrow was almost 1,000 miles into its 9,000-mile journey, with passengers settling down for a very long overnight trip, when a man in the economy cabin, believed to be aged about 30, suddenly stood up and started shouting. One passenger described him acting in “an extremely aggressive manner”.

Clare Hudson, who was holding her baby about four rows in front of the man, told The West Australian: “There was a gentleman who locked himself in one of the toilets for about an hour.

“When he came out he started acting really aggressive and it looked like he was going to attack another one of the passengers.

“Luckily they did manage to calm him down after a few minutes and took him up the back of the plane.”

With around two hours of the flight completed, the options open to the flight crew were to continue to London with the passenger restrained; to divert, probably to Singapore; or to return to Perth.

Carrying on to Heathrow would have placed extra pressure on cabin crew and risked further disruption.

Round trip: path of Qantas flight QF9 from Perth on 8 September (Flightstats.com)

Any diversion on this ultra-long-haul flight means the crew will not have enough hours remaining to complete the journey – though touching down at Singapore, about three hours’ flight time away, would have allowed some passengers to reach London on other flights without too much delay.

Instead, the captain decided to return to Perth, where the flight landed almost four hours after the original take-off.

The disruptive passenger was led from the aircraft by Australian Federal Police, and immediately placed on the Qantas “no-fly” list.

A spokesperson for the Australian airline said: “This type of disturbance inconveniences our customers but we take a zero tolerance approach to disruptive behaviour on board.

"The passenger has been issued with an interim 'no fly ban' which means they are unable to travel on Qantas Group flights until the investigation into the matter is completed."

The remaining passengers were given hotel rooms overnight, the meals on board were thrown out, and the 17-hour flight to London finally took off 18 hours late. It touched down at Heathrow at 10.30pm on Sunday night.

The following flight from Perth arrived only six hours later.

More than 200 passengers were waiting to fly from Heathrow to Perth on Sunday. Those who were planning connecting flights from Perth were rebooked on alternative departures. The remainder left over 10 hours late – taking off after midnight, beyond the airport's usual curfew of 11.30pm, with an expected arrival time in Perth shortly before midnight on Monday.

A guide to the Qantas Perth flight - The longest nonstop scheduled passenger flight ever from a UK airport

Airlines are allowed a quota of departures from Heathrow after the normal curfew of 11.30pm in exceptional circumstances. The alternative would have been to delay the Qantas flight by six more hours.

The Department for Transport says: “There are occasions when a scheduled departure is unavoidably delayed because of operational or technical problems.

“If a flight needs to leave after 11.30pm for these reasons, the airline must request permission and explain the reason for the delay.”

On ultra-long-haul flights, the consequences of “air rage“ are often disproportionately high.

With wasted fuel, and the bill for accommodation, meals and rebooking for delayed passengers, the cost of the disruption is likely to reach around A$180,000 (£100,000).

Besides the likelihood of criminal charges, the perpetrator may be ordered to pay for the costs incurred.