This article needs additional citations for verification. (October 2008) (Learn how and when to remove this template message)
As few as four aircraft can establish the formation and conventionally the largest number is sixteen, in "tight formation": 1, 2, 3, 4, 3, 2, 1. Rarely attempted on jet aircraft, this feat was first achieved by the Pakistan Air Force flying U.S.-made F-86 Sabres in February 1958. It is considered a difficult formation as the aircraft have to fly very close to each other to create the desired effect. The larger the number of aircraft involved, the higher the risk (as compared to other formations).
A formation in association football where the four midfield players are positioned in the shape of a diamond.
A defensive formation used during a penalty kill.