Peter Bellew, the current head of Malaysia Airlines, is to rejoin Ryanair, the Irish company has announced.
Mr Bellew had worked at Ryanair for almost a decade, before leaving the airline in 2015.
He joined the Malaysian carrier as COO, during a period when the airline was facing massive financial losses. It had also suffered two major disasters in 2014.
Mr Bellew became CEO of Malaysia Airlines last year.
The airline executive will now rejoin Ryanair as Chief Operations Officer, and oversee the company's flight, ground & engineering operations.
However, the airline says Mr Bellew will have a specific responsibility for "pilot production, training and career development" - in a bid to avoid a repeat of last month's rostering problems that led to thousands of cancelled flights.
Ryanair boss Michael O’Leary explained: “We are pleased to welcome Peter back to Ryanair. Having worked previously in a senior role in our Operations team, Peter has an unrivalled knowledge of our business model and how we maintain controlled growth.
"Peter will lead a significant transformation in the way we reward and interact with our pilots, improve their working environment and career development over the coming years."
Mr Bellew added: “I am excited to return home to Ryanair and take up the challenge to grow the operation sustainably. I look forward to working with all the team and all the crews I know so well to further develop our growth to 600 aircraft over the next 6 years.”