遨游天际

Humans（人类） dont have wings（翅膀）. So how can we fly？ By plane！ Planes are much faster than trains，cars and boats. And there are many kinds of planes.

People believe that in 1903，the Wright brothers（莱特兄弟） from the US invented（发明） the worlds first plane. They flew 36.5 meters in 12 seconds（秒）.

Do you know the double-decker（双层的） bus？ It is usually bigger and carries（運载） more passengers（乘客） than normal（普通的） buses. Here is the double-decker bus in the air. Its（它的） name is Airbus A380. It is the largest passenger plane in the world. The plane is 73 meters long and 79.8 meters wide. It is as large as half a football field.

In the plane，there are about 555 seats for passengers. Thats a lot more than normal planes.

Some planes are good at carrying passengers，and some are good at fighting（战斗）. This is the B-2 Strategic Bomber（战略轰炸机） from the US. Doesnt it look strange？ B-2 is made of some special materials（特殊材料）. With these materials，radars（雷达） cant find the plane.

Planes fly high in the air. But space shuttles（航天飞机） fly higher than planes.

Space shuttle sends astronauts（航天员） and satellites（卫星） into space. It has wings and a body like planes. But a space shuttle can not fly itself. It needs a fuel tank（油箱） and two rockets（火箭） to help it fly to the space.