Liaison aircraft

A liaison aircraft (also called an army co-operation aircraft) is a small, usually unarmed aircraft primarily used by military forces for artillery observation or transporting commanders and messages. The concept developed before World War II and included also battlefield reconnaissance, air ambulance, column control, light cargo delivery and similar duties. Able to operate from small, unimproved fields under primitive conditions, with STOL capabilities, most liaison aircraft were developed from, or were later used as general aviation aircraft. Both fixed-wing aircraft and helicopters can perform liaison duties.