Wiktionary
n. a small, usually unarmed aircraft primarily used by military forces for artillery observation or transporting commanders and messages.
Wikipedia
A liaison aircraft (also called an army cooperation 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.
Usage examples of "liaison aircraft".
Simultaneously, small liaison aircraft (Piper Cubs) appeared over Beach Red, and marked its 3200 yard width with smoke grenades.
The L-4, essentially a Piper Cub, was the two-passenger, high-wing, low-and-slow observation and liaison aircraft that preceded the Cessna L-19.
Almost immediately, small liaison aircraft appeared over Beach Red and marked its 3,200 yard width with smoke grenades.
Failing proficiency tests for fighter pilots, he was relegated to flying support and liaison aircraft, in which service he built up quite a nice little trade in American cigarettes, vodka, caviar, nylon stockings, hard currency, and other articles of small bulk and high profits.
That the raid occurred within easy range of the liaison aircraft aboard the Alamo?