British Airways has temporarily stopped selling flights during the planned strike period.
The airline is not taking bookings for travel between May 19 and June 9 for travel in or out of Heathrow airport, while it finalises its schedule.
BA said all flights would continue to operate out of Gatwick and London City during the walkout, as well as a substantial number of long haul flights from Heathrow.
It pledged to run a number of flights to every short haul destination in its network.
The industrial action will last 20 days over a 23 day period, with four five-day strikes.
The dates are:
May 18 to 22
May 24 to 28
May 30 to June 3
June 5 to 9