The flying trapeze is a specific form of the trapeze in which a performer jumps from a platform with the trapeze so that gravity makes the trapeze swing.

In a traditional flying trapeze act, flyers mount a narrow board (usually by climbing a tall ladder) and take off from the board on the fly bar. The flyer must wait for a call from the catcher to make sure he or she leaves at the correct time. Otherwise, the catcher will not be close enough to the flyer to make a successful catch. The flier then performs one of many aerial tricks and is caught by the catcher, who is swinging from a separate catch bar. Once in the catcher's hands, the flyer continues to swing and is thrust back toward the fly bar in a maneuver called a "return"

(Source: Wikipedia)