A woman who mistakenly boarded a Qantas Airways flight in Los Angeles, believing the flight was heading for Hong Kong, arrived in Melbourne because of an out-of-service computerised boarding system.
The passenger realised the mistake just minutes before landing in Melbourne.
The woman had a boarding pass for a Cathay Pacific flight from Los Angeles to Hong Kong when she mistakenly got on an earlier Qantas flight departing from the same gate at Los Angeles LAX airport, a Qantas spokesperson said.
The spokesperson said the electronic boarding pass readers, which would have identified the boarding pass error, were "out of service".
"The ground staff conducted manual boarding procedures and didn't notice the error."
Qantas made arrangements for the woman to stay in Melbourne on Sunday night, and put her on a Qantas flight to Hong Kong on Monday.
Because the woman did not turn up for her Cathay Pacific flight, her luggage was kept in Los Angeles, but it was flown on to meet her in Hong Kong on Monday.
Qantas officials could not confirm if a similar boarding hitch had happened before, but claimed it would be rare.