So that it can fly with light and fast velocity, an object needs to be air-borne or buoyant. The adverb of flight describes actions taken to achieve flight. The most common words used as adverbs of flight are easily, quickly, and farther. These words are used to describe how far an object has flown or will fly. An object that is easy to fly is called a light aircraft. One that is more difficult to fly is called a heavy aircraft. Heavy objects are more likely to have serious accidents during takeoff or landing because they require more force to move them forward on the runway. Light objects are usually small planes that can turn very easily. They are not as dangerous as heavy planes because if an engine fails they can glide for a long distance before crashing. When you tell someone what kind of aircraft you are flying they can say whether it is heavy or light by looking at the size of the plane. Smaller planes are light while larger ones are heavy. Heavy aircraft need more time and space to take off than light aircraft. This is because they must overcome greater forces trying to stop them from moving.