American Airlines' new Flagship Suite business class is set to enter service in June. Here's where you can fly it first.

American Airlines’ new suites with sliding doors are set to start flying on some of its planes in June, a key part of its strategy to compete against more profitable rivals for high-spending customers.

Traveling by plane usually involves feeling cramped with little space between fellow passengers and luggage. But American Airlines plans to sell tickets that offer an upgrade from a seat to a whole suite.