F3J is one of many competition categories for model and full scale aircraft that are defined by the Fédération Aéronautique Internationale (FAI). F3J is a man on man thermal soaring competition undertaken on a flat field site (ideally 1–2 miles from workable slope lift). Models are launched by a monofilament tow line, pulled by two towers who run with the line or a pulley. The method is similar to winch launching without any electrical equipment required. A group typically of from 6 to 10 pilots try to fly for as long as possible within a 10-minute period of time (known as a slot). Within the slot time they have to launch the glider, fly for as long as possible and land as close as they can to a predetermined spot, without overflying the end of the slot time. If the nose of the model comes to rest on the centre of the landing spot then 100 landing points are scored. Landing points are reduced by 1 point every 20 cm from the center of the landing circle. A combination of the flying time (as a percentage of the longest flight within the slot) and precision landing makes up scoring. A maximum of 1000 points is awarded to the winner of each group. Overflying the slot time results in a penalty and the withdrawal of any landing points bonus.