Deregulation of the US airline industry gave a lot of companies, both new and existing, their opportunity to take on the big Trunk airlines and carve a niche for themselves. One that made a success of its opportunity was American Trans Air, which grew from a one plane travel club in the 70s to the USA's largest charter airline by the mid 1980s.
The 707s were only ever stopgap equipment and the series 123Bs were replaced as early as December 1983 by a quartet of ex-United Airlines Boeing 727-22s. A further four 727-100s would join the fleet in 1985. The 727s were used to open up new scheduled flights from Indianapolis to four destinations in Florida, Puerto Rico and Las Vegas from May 1986.
Regardless of the loss of the DC-10 by 1986 the airline was the largest charter carrier in the USA. It would continue to grow its fleet into the 1990s adding more Tristars and also Boeing 727-200s and 757-200s. Throughout the 1990s ATA would morph into a very different airline and eventually in April 2008 it would cease operations after four humbling years post bankruptcy. Ambassadair Travel club meanwhile actually still operates having been sold in 2005 to Grueninger Travel Group. Mikelson's airline tried its hand at many things throughout its nearly 40 year history but it was never more successful than when it took deregulation by the horns and expanded into a successful charter airline during the 1980s.
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