100 yards distance outdoors. Targets vary, but generally, the ISSF 50M (scaled) is used for 50 yards or 50 metres, and a proportionally sized target is used for 100 yards. A 50-yard, 50-metre or 100-yard target is generally constructed to allow 20 shots to count, to be executed during one 'detail' of 20 minutes duration. Sighting shots are included in that time period. Outdoors, variables such as light, wind, temperature, humidity and mirage affect the target image and bullet trajectory. To help shooters, most ranges have wind flags placed at useful positions around the range to display the wind conditions. Pilots The prone position is also used to describe the way pilots and other crew may be positioned in an aircraft; lying on their stomachs rather than seated in a normal upright position. During World War II, the bomb aimer in some bombers would be positioned this way to be better able to view the ground through a transparent panel or bubble in the nose of a bomber. Later, it was suggested that a pilot in the prone position might be more effective in some kinds of high-speed aircraft, because it would permit the pilot to withstand a greater g-force in the upward and downward direction with respect to the plane, and many speculative designs of the 1950s featured this arrangement. However, it never became mainstream, as testing revealed that the increased difficulty of operating aircraft controls in the prone position outweighed the advantages. Two examples of this approach are seen in the Savoia-Marchetti SM.93 and the Gloster Meteor F8 "Prone Pilot". Modern hang gliders are typically piloted in the prone position. See also Lying position Positional asphyxia Prone bike Proning Recovery position Supine position Tummy time References Sources Etymonline Anatomy Shooting positions Human positions