A five-day strike by British Airways cabin crew has begun after last minute talks with the Unite union broke down.
All flights from Gatwick and London City are expected to run as normal, with the disruption confined to Heathrow.
The airline pledged to run 60% of long haul and 50% of short haul flights from Heathrow.
It is expected to lease eight aircraft from other airlines.
Unite joint secretary Tony Woodley said he would stop the walkout if the airline promised to reinstate travel perks for its members who took part in the March strikes.
However, BA said it had already agreed to do so once the union had accepted its deal in full.
If the two sides fail to reach an agreement, more strikes will follow from 30 May and 5 June.
Speaking on the BBC’s The Andrew Marr Show, BA chief executive Willie Walsh pledged to keep BA flying during the walkout. He said: “We will not be grounded by the actions of a tiny minority who are clearly out of touch with reality.”
Talks on Saturday broke down when Socialist Workers’ Party protesters put a halt to the meeting.
More than 100 demonstrators gathered outside the building, saying they were there to show solidarity with BA cabin crew.
In another twist, Walsh slammed joint leader of Unite Derek Simpson for sending out Twitter updates during meetings.
He said: “I didn’t realise he was actually sending his version of events to wider audience. That really did undermine my confidence in their desire to resolve this issue.”