From 1919 until 1924, the

United States Army Air Service The United States Army Air Service (USAAS)Craven and Cate Vol. 1, p. 9 (also known as the ''"Air Service"'', ''"U.S. Air Service"'' and before its legislative establishment in 1920, the ''"Air Service, United States Army"'') was the aerial war ...

used a system to designate the types of aircraft it was operating, based on role and specific characteristics of the

aircraft An aircraft is a vehicle that is able to fly by gaining support from the air. It counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engines ...

. When first instituted,

Roman numerals Roman numerals are a numeral system that originated in ancient Rome and remained the usual way of writing numbers throughout Europe well into the Late Middle Ages. Numbers are written with combinations of letters from the Latin alphabet, eac ...

were used to number the designations in use. These numerals were only applied to the first 15 types before being abandoned.

Air-cooled Air-cooled engines rely on the circulation of air directly over heat dissipation fins or hot areas of the engine to cool them in order to keep the engine within operating temperatures. In all combustion engines, a great percentage of the heat ge ...

and

Water-cooled Cooling tower and water discharge of a nuclear power plant Water cooling is a method of heat removal from components and industrial equipment. Evaporative cooling using water is often more efficient than air cooling. Water is inexpensive and non ...

refer to the engines installed, while Pursuit was the name given to fighter aircraft in the

US Army The United States Army (USA) is the land service branch of the United States Armed Forces. It is one of the eight U.S. uniformed services, and is designated as the Army of the United States in the U.S. Constitution.Article II, section 2, cla ...

, at that time. The system was replaced by the

1924 United States Army Air Service aircraft designation system In 1924, problems with the previous designation system led to a general revamping of the designation system used by the United States Army Air Service. This system was to remain in effect with the U.S. Army Air Corps, the U.S. Army Air Forces an ...

List of designations

Source: BridgesBridges, 2006

References

Citations

Bibliography

* John M. Andrade, ''U.S. Military Aircraft Designations and Serials since 1909'', Midland Counties Publications, England, 1979, * {{US military navbox American military aviation United States Army Air Forces lists

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...