British Airways (BA) plans to get 60% of passengers to their final destination during the first three days of the upcoming cabin crew strike, due to start on Saturday.
BA aims to fly around 45,000 customers each day between March 20 and 22.
The airline has stopped taking bookings for the days affected by strike action, which also include March 27, 28, 29 and 30.
BA also said "many thousands more" customers will be offered seats with alternative airlines, or on other BA flights.
All long haul Gatwick flights will operate, as well as more than half of short haul flights at the airport. All flights to and from London City will also be unaffected.
At Heathrow, BA said it will operate 60% of longhaul flights to and from the airport during the first three days of the strike.
Some shorthaul routes from Heathrow will be operated by BA, and the airline will also lease up to 22 aircraft with pilots and crews, enabling the airline to operate around 30% of its shorthaul schedule.
In addition, BA has also agreed with 40 other carriers that customers can be rebooked free of charge during the actual strike period onto their flights if they had been due to travel on a BA flight which has been cancelled.
The cabin crew union Unite has called the strike in response to a dispute over pay and working conditions. It dismissed BA's flight schedule for during the strike action as "a work of fantasy"
BA said it has not ruled out further negotiation with Unite. "The airline is still available to hold further talks but wants customers to have early warning of its flying schedule to allow sufficient time for alternative travel arrangements to be made," said BA.
Willie Walsh, British Airways' CEO, said: "We are deeply sorry that our customers are the innocent victims of this cynical attack on their travel plans by the leaders of Unite.
"Despite the desire of Unite's leadership to ground the airline, the flag will continue to fly. Around 60 per cent of our customers will be able to fly as planned and many thousands more can be rebooked onto alternative BA flights or onto rival airlines.
"I recognise the frustration of customers booked for travel from March 27 onwards, when the second stoppage is due to begin, and we will do all we can to give them more clarity about their specific flight number once we start to understand just how many cabin crew are willing to work as normal."
For more information about which flights will be operating, visit www.ba.com
BA has also launched a freephone disruption number for members of the travel trade to call, to discuss issues relating to the strike threat: 0800 727 800.