Goal (sport) placed at each end of the playing field. Each structure usually consists of two vertical posts, called "goal posts", supporting a horizontal "crossbar". A "goal line" marked on the playing surface between the goal posts demarcates the goal area. Thus, the objective is to send the ball or puck between the goal posts, under or over the crossbar (depending on the sport), and across the goal line. Less commonly, as in basketball or netball, goals are ring-shaped. The structure is often accompanied with an auxiliary net, which stops or slows down the ball when a goal is scored. In some
Position error free-stream pressure is a minimum across the operating range of angle of attack of the aircraft. The residual error at any given angle of attack is called the position error. Position error affects the indicated airspeed and the indicated altitude. Aircraft manufacturers use the aircraft flight manual to publish details of the error in indicated airspeed and indicated altitude across the operating range of speeds. In many aircraft, the effect of position error on airspeed is shown as the difference between indicated airspeed and calibrated airspeed. In some low-speed aircraft, the position error is shown as the difference between indicated