Willie Walsh has passed control of IAG to Luis Gallego at the Aer Lingus and Iberia owner's annual meeting today, where shareholders were also asked to stump up billions of euros to help it through the coronavirus crisis.
Former pilot Walsh delayed his departure from International Consolidated Airlines Group, which he created by dragging British Airways and Iberia into the modern age of budget flying.
Wille Walsh took a tough line on unions and cutting costs.
IAG later added Aer Lingus and Vueling to the group.
Walsh had been CEO of BA since 2005 and of IAG since it was created in 2011.
Gallego, a Spanish insider who turned around Iberia, will have to cut costs, while managing damaged relations with unions and politicians and stepping up the group's battle with Ryanair and EasyJet.
IAG's position is expecting to be strengthened by raising €2.75 billion from shareholders in a rights issue which is backed by its biggest shareholder Qatar.
"Major shareholders are satisfied that IAG's equity raise will be enough to weather the crisis - or at least that's their hope," one banking source told Reuters.
At BA, where 12,000 jobs are set to go and new terms have been set for long-serving staff, unions have vowed to fight and the British government said the plan was a "breach of faith" after it accessed state funds to pay wages during the crisis.
Gallego will also have to restore services, the airline was only flying 20% of its pre-Covid 19 schedule last month, and stem a cash outflow of £20m a day.
Meanwhile, IAG said today it had obtained the necessary approvals to continue flying if no free-trade deal is agreed between Britain and the European Union.
"In compliance with the European Union connectivity regulation last year our airlines submitted their plans on ownership and control to the respective national regulators in Spain and Ireland," Chairman Antonio Vazquez told the group's AGM in Madrid, which was live streamed.
"We're delighted to announce that regulators confirmed that these plans in case of a hard Brexit do comply with European Union connectivity regulations", the chairman added.