The air-cushioned① vehicle does not have wings， so it is not an airplane. It is neither a ship nor an automobile， since it travels clear of sea and land. It has a conventional gasoline② engine， but no wheels. How does it travel？What keeps it in the air？
Under the air-cushioned car is an air chamber， in which there is a large propeller③ parallel to the ground. The propeller whirl through the power supplied with gasoline engine， so that the chamber is filled with air. Some of the air is forced toward the ground through tiny holes around the edges of the air car.
These air jets create a wall which keeps the air from escaping from the chamber. As more and more air crowds into the chamber， the molecules of air become compressed④. As a result， their pressure becomes so strong that it lifts the car off the ground.
Once the car is floating， the driver releases some of the compressed air， which makes the car speed forward.
① cushionv. 给……安上垫子，缓和……的冲击
② gasolinen. 汽油［U］
③ propellern. 螺旋桨，推进器［C］
④ compressedadj. 压缩的
脱离海面和陆地行驶的气垫船
因为气垫船没有双翼，所以它不是飞机。它不是轮船，也不是汽车，因为它脱离海面和陆地行驶。气垫船装有常规的汽油发动机，但没有轮子。它怎样行驶？什么使它悬在空中？
气垫船下面是一个里面装有一个与地面平行的大螺旋桨的空气箱。当汽油发动机供能后，就能螺旋桨旋转起来，因而气箱内充满了空气。部分空气通过气垫船边缘的小孔被压向地面。
这些喷射出的气流形成一道阻止空气从气箱中逸出的屏障。正是由于越来越多的空气聚集在气箱内，使空气分子受到压缩产生强大的压力，从而使汽垫船脱离地面。
当汽垫船浮动时，一部分压缩空气会被司机释放出来，推动汽垫船高速向前飞行。
