"空军一号"对很多人来说是一个比较陌生的概念，它的真实面目到底是什么样的？

　　Q: What is Air force One?

　　A: Air Force One is a prominent symbol of the United States in general and the office of the presidency in particular (在特殊意义上是总统职权[的象征]). Whenever the president travels overseas or across the country, he takes his high-tech jumbo jet ([能载300名以上乘客的]巨型喷气式飞机，珍宝机) with him. On September 11th, the president's plane showed that it was much more than an executive jet ? it became a mobile bunker(掩体) when all ground positions seemed vulnerable to attack.

　　Q: Is Air Force One technically a plane, as general public think it is?

　　A: Air Force One isn't technically a plane: It's simply the radio call name(无线电通讯中所用的名称)for any U.S. Air Force plane carrying the president of the United States. As soon as the president steps aboard an Air Force plane, that plane is referred to as Air Force One by the crew and all air traffic controllers, insgroupsto avoid confusion with any other planes in the area. If the president rides on an Army aircraft, that aircraft is Army One (陆军一号), and whenever he boards his specialized helicopter, that craft is Marine One (海军一号). Civilians generally refer to the physical plane itself as Air Force One, of course, and we will in this article too.

　　Q: What are the special features of Air Force One?

　　A: Because Air Force One carries the president, and because some trips can be quite long, the plane has a number of special features, many of which are found on no commercial airliner.

　　The most remarkable feature on the plane is its extensive electronics. It has 85 onboard telephones (机载电话), a collection of two-way radios, fax machines and computer connections. It also has 19 televisions and assorted (各种各样的) office equipment. The phone system is set up for normal air to ground connections and secure lines. The president and his staff can reach just about anybody in the world while cruising (航行) tens of thousands of feet in the air. Another special addition is the in-flight refueling (给……添加燃料) connection. As with the B-2 and other combat craft, in-flight refueling gives Air Force One the ability to stay up in the air indefinitely, which could be crucial in an emergency situation.

　　Q: What does Air Force One look like?

　　A: It is almost as tall as a six story building, and as long as a city block. It has four General Electric CF6-80C2B1 jet engines, which provide 56,700 pounds of thrust a piece. The top speed is between 630 and 700 miles per hour and the ceiling maximum (how high the plane can fly) is 45,100 feet. It carries 53,611 gallons of fuel and weighs 833,000 pounds fully loaded for a long-range mission. With a full tank, the plane can fly halfway around the world.

　　Air Force One has 4,000 square feet of interior floor space. Much of it looks more like a hotel or executive office than a jetliner, except for the seatbelts on all the chairs. Like a normal 747, it has three levels. But the inside, the plane doesn't resemble commercial 747s in the slightest.

　　The lowest level of the plane mostly serves as cargo space. Most of the passenger room is on the middle level, and the upper level is largely dedicated to communications equipment.

　　The president has onboard living quarters, with his own bedroom, bathroom, workout room and office space. Most of the furniture on the plane was hand-crafted by master carpenters.

　　Q: How does Air Force One operate in flight?

　　A: Every Air Force One flight is classified as a military operation, and it is handled as such. Air Force crews at Andrews Air Force Base in Maryland carefully inspect the plane, and the runway, before every flight.

　　When it's time to head off, the Marine One helicopter brings the president from the White House to Andrews Air Force Base. Teams all over the base keep an eye out for any unauthorized craft in the area and are authorized to shoot on sight. In advance of every Air Force One flight, the Air Force crew sends C141 Starlifter cargo carrier planes, toting (运送) the president's motorcade (总统外出的车队), to the destination. This collection of bulletproof limousines([尤指驾驶室与后座间用玻璃隔开，通常由专职司机驾驶的]豪华高级小客车) and vans, loaded with weaponry, keeps the president safe on the ground.

　　The president always arrives at the base with "the football," the briefcase that holds the codes for nuclear deployment. An Air Force officer guards the football for the entire flight, before passing it off to an Army officer on the ground.

　　Just like a normal jetliner, Air Force One has a crew to fly the plane and a steward crew to prepare and serve meals and to clean the aircraft. These crew members are carefully screened(筛选，审查) military personnel, with exemplary service histories. Even the crew members who prepare meals must operate with a high level of security. For example, when buying food, they must hit the stores undercover, and they must select markets at random, insgroupsto protect the president from a poison attack. Onboard the plane, the crew provides 24-hour first class service.

　　These crew members enjoy a very rare privilege? they get to work alongside the president when he is at his most relaxed. Every president since Harry Truman (杜鲁门总统) has formed close connections with his flight crew, and the final Air Force One flight is always an emotional trip.