Warren Buffett's investment firm Berkshire Hathaway has upped its stake in American Airlines (NASDAQ: AAL) and Southwest (NYSE: LUV) while dumping stock in fellow billionaire Rupert Murdoch's 21st Century Fox.
Berkshire also offloaded eight percent of its Delta Air Lines (NYSE: DAL) holdings, leaving it with 55 million shares worth $2.53 billion at the end of March.
Buffett once called the airline industry a "deathtrap" but is now, through his company, among the largest shareholders in American, Delta, Southwest and United Continental Holdings (NYSE: UAL.NYSE).
In the first quarter Berkshire's lifted its stake in American Airlines by eight percent to 49.3 million shares worth $2.08 billion.
It also increased its stake in Southwest by 10 percent to 47.7 million shares worth $2.57 billion.
The billionaire investor told shareholders at the Berkshire AGM earlier this month that airlines business models had improved significantly with fewer unsold seats and a newfound tendency to charge for many services and amenities that were once offered free of charge.
While Berkshire strengthened its position in the aviation sector it pulled back from media and publishing by selling all its shares in 21st Century Fox.
The $251 million exit from Fox comes as the company's news network reels from a sexual harassment scandal involving top Fox news host Bill O'Reilly.
O'Reilly paid about $13 million to settle harassment claims by five women and was dropped by Fox News.
It is not clear why Berkshire dumped its Fox shares that it only bought in 2014 shortly after the company was spun off from News Corporation.
It also decreased its stakes in IBM (NYSE: IBM) and commercial vehicle parts supplier Wabco Holdings (NYSE: WBC).
Berkshire also owns $18.6 billion of Apple (NASDAQ: AAPL) stock and increased its holdings in Bank of New York Mellon Co (NYSE: BK), satellite radio operator Sirius XM Holdings (NASDAQ: SIRI).
The company own 90 businesses including Geico car insurance and Dairy Queen ice cream.