American Airlines on Wednesday unveiled its first retrofitted Boeing 777-300ER aircraft, a model primarily used for its popular long-haul international routes. The new configuration includes 144 premium seats, 70 of which are lie-flat Flagship Suites with sliding doors. The company plans to complete the retrofit of all 20 Boeing 777-300ER aircraft by the end of next year to catch up with competitors and cater to high-spending travelers.