British Airways (BA) is having to cancel flights as the fall out from its pilots' two-day strike are felt.
BA has warned it will take "some time" for flights to get back to normal, despite the end of the strikes.
BA pilots walked out on Monday and Tuesday, for the first time in the airline's history, in a row over pay resulting in over 1,700 flights being cancelled and around 195,000 passengers affected.
Today, the airline has said that 150 aircraft are out of place, along with more than 700 pilots and 4,000 cabin crew.
"The nature of our highly complex, global operation means that it will take some time to get back to a completely normal flight schedule," BA said.
"Due to the union's strike action, nearly half of our fleet of over 300 aircraft and more than 700 pilots will start the day in the wrong place [on Wednesday].
"In addition, more than 4,000 cabin crew have had disruption to their rosters, and in many cases will be unable to operate again for several days due to legal rest requirements."
BA is expecting further disruption in the coming days as it tries to get customers to their destinations.
The airline is offering affected customers refunds or the option to re-book to another date of travel or an alternative airline.
The British Airline Pilots Association (BALPA) says the two-day strike action was a powerful demonstration of the strength of feeling of BA pilots.
BALPA has urged the airline back to the negotiating table with some meaningful proposals to try to avert the next scheduled strike on 27 September.
BALPA calls on BA to return to negotiations with something positive to resolve this dispute and try to prevent the next strike action on 27 September.
Should British Airways refuse meaningful negotiations, further strike dates will be considered by the BALPA national executive team.
BALPA general secretary, Brian Strutton, said: "Surely any reasonable employer would listen to such a clear message, stop threatening and bullying, and start working towards finding a solution."