Gen Re promoted John Brogan to chief executive officer of an aviation unit as the reinsurer at Warren Buffett’s Berkshire Hathaway Inc. phases in a new generation of leadership.

Brogan replaces David McKay, who plans to retire in April after almost 40 years at United States Aviation Underwriters, the company said in a statement Thursday. Brogan is currently the president and chief operating officer, overseeing underwriting and claims operations.

Ajit Jain, one of Buffett’s top deputies at Berkshire, has been shuffling management at Gen Re since taking responsibility for the business this year. Tad Montross, who previously led the reinsurer, announced his departure in April, and Jain promoted Kara Raiguel to run that operation in May.

Berkshire was among the five largest insurers for aircraft risks in the U.S. and Canada in 2014, and competes with firms including American International Group Inc. and Allianz SE for that business, according to data compiled by the National Association of Insurance Commissioners. The market for aviation insurance was about $1.7 billion of premiums written in 2014. That year included losses by Malaysia Airlines and TransAsia Airways Corp. and was “tumultuous” for insurers, but the industry started to stabilize in 2015, according to a report from Wells Fargo & Co.

‘Unique Perspective’

The aviation insurer “benefits greatly from John’s leadership and vision for the future,” McKay said in the statement. “He brings a unique perspective to the task ahead of him. Under his direction, USAIG will continue as a global leader in aviation insurance.”

McKay has previously worked at Aerospace Management Services International, and held roles including chief underwriter and chief operating officer while at United States Aviation Underwriters, according to the statement. Brogan joined the company in 1997, and was promoted this year to president and COO.

USAU is a subsidiary of Gen Re and manages United States Aircraft Insurance Group, which is a pool of insurers including Chubb Ltd. and Liberty Mutual Holding Co. according to its website.