Idflieg aircraft designation system

The Idflieg designation system was used to designate German heavier-than-air military (as opposed to naval) aircraft from the early days of the Fliegertruppe/Luftstreitkräfte to the end of World War I. The system necessarily evolved during this period, as new aircraft types were produced.

At times complicating the identification of wartime German aircraft is the fact that German manufacturers not only typically used their own designations; but also sometimes gave their experimental productions unofficial "Idflieg-style" class numbers, or even built on them, perhaps in the hope of production orders. The "Rs" (giant seaplane), and "CLs" (two-seater seaplane) designations of the Zeppelin-Lindau company are examples, as are the unofficial "Dr" designations of the experimental Euler triplanes, which in fact were never given official designations.

The German Navy had their own system for classification of aircraft types, but did not use this, nor the Luftstreitkräfte system, to designate particular aircraft types, preferring to use manufacturers' designations. Airships were totally outside either system, being individually numbered in the same way as German destroyers and submarines, mostly in the "L" series.

As well as serving to identify types, the Idflieg type designations were also often included as part of German aircraft serial number markings.

Each designation consisted of one of the following letters, followed by a Roman numeral. For example, the first "D"-class aircraft built by Albatros was designated the Albatros D.I, the second, the Albatros D.II and so on.

The system ceased to apply with the end of German military aviation following the Armistice, and aircraft of the newly reborn Luftwaffe would be designated according to the RLM aircraft designation system, although in the nineteen twenties and thirties the Fokker company designated its new military types with "Idflieg" style numbers, so as to continue war-time sequences. In particular Fokker two seat military reconnaissance aircraft continued the wartime "C" series, while Fokker single-seater fighters were given numbers in the "D" series exploiting the reputation of the wartime D.VII.

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