US Airways CEO Doug Parker is one of his favorite executives, Cramer said, adding that with the deal, four carriers will dominate the industry.
"You want some bold predictions?" he asked. "The ... deal is so unbelievably great for US Air that I believe this stock could catapult. ... The stock could double."
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US Airways Group and American Airlines made the merger announcement Tuesday after settling a lawsuit with the Department of Justice, which sought to block the union on concerns it would drive up fares and hinder competition.
As of early Wednesday afternoon, US Airways shares hovered between $23.13 and $24.30. The merger was part of American's effort to end a two-year bankruptcy process.