These features make Air Force One an incomparable 'flying fortress'

Embellished with the American flag, the presidential seal, and the words United States of America, the world's most famous plane is as tall as a six-story building and gives an undeniable authoritative presence wherever it flies.

The three-leveled "flying Oval Office" is a custom Boeing 747-200B that has 4,000 square feet of interior floor space, including a conference room, dining room, private quarters for the president, offices for senior staff members, a medical operating room (a doctor flies on every flight), press area, two food-preparation galleys that can provide 100 meals, and multifrequency radios for air-to-air and air-to-ground communication.

President Obama's Air Force One is the most expensive to operate, costing taxpayers $206,337 every hour the world's most famous plane is in flight, according to a Freedom of Information Act (FOIA) letter obtained by the nonprofit Judicial Watch.

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