Finger-four

One disadvantage of the finger-four formation was that it left the least-experienced flier, the number two wingman, in the most exposed position (as "tail-end Charlie").

[citation needed] During the 1930s, the Finnish Air Force, aware of its weakness in numbers compared to its neighbours, sought to offset the disadvantage by a radical rethink of its tactics.

The new tactical philosophy emphasized aggression, a willingness to attack regardless of the odds, as well as shooting accuracy at a time when aerobatic skill was prized by most air forces.

With no guarantee of success, the FAF adopted the new tactics and was later to find the validity of this approach during the Winter War (1939–1940) with the Soviet Union.

[2] Involvement in the Spanish Civil War gave the fledgling Luftwaffe an early experience of combat conditions, but the "Condor Legion" quickly found its main fighter aircraft, the He 51, was outclassed by the Soviet I-16 in service with the Republicans.

Flying in pairs (Rotte) or a two-pair Schwarm and using a more open formation (made possible by radio communication between aircraft) was found to confer other benefits.

The Soviet Air Force units in the Spanish Civil War soon adopted the formation flying against the Germans and in 1938 recommended its use when they returned home.

However, most of the Spanish veterans were swept away during Stalin's Great Purge of the armed forces,[3] and the more conservative "Vic" remained the standard Soviet formation.

[5][6] The United States Army Air Corps and Naval Aviation began using a concept called "Fighting Pair" from 1940 to 1941.