Reichsluftfahrtministerium aircraft designation system

The German Air Ministry (Reichsluftfahrtministerium; RLM) had a system for aircraft designation which was an attempt by the aviation authorities of the Third Reich to standardize and produce an identifier for each aircraft design's airframe type produced in Germany. It was in use from 1933 to 1945 though many pre-1933 aircraft were included and the system had changes over those years. As well as aircraft of the Luftwaffe, it covered civilian airliners and sport planes, due to the RLM handing all aviation-related matters in the Third Reich, both civilian and military in nature.

When the Reichsluftfahrtministerium was given control of the country's aviation activities in 1933, it set out to catalog both the aircraft already in production by various German manufacturers as well as new projects approved for development by the ministry. The RLM made necessary improvements to a designation system which had been set up in 1929/30 by the Heereswaffenamt (Army Weapons Office) in the Reichswehrministerium (Defense Ministry), together with other institutions related to the industry. The former system had caused confusion in the use of aircraft designations among the different manufacturers; six aircraft of different firms used the number 33.

The improved designation system was introduced in order to provide a simple and unambiguous identification of every German civilian and military aircraft, be it fixed-wing or rotary-winged, and its corresponding airframe design. The heart of the new system was a (theoretically) unique number assigned by the RLM. In internal paperwork, this number was simply prefixed "8-" (or, in the case of sailplanes, subject to a separate numerical list, "108-"), while "9-" indicated aircraft engines, with 109 prefixing reaction engines (gas turbines, pulse-jets and rockets). The new standardized type designation added two letters representing the manufacturer; Dornier (Do) and Rohrbach (Ro) already used this practice. The first of these two letters was shown in upper case, the second always in lower case, no matter its origin – so Fw for Focke-Wulf or Bf for Bayerische Flugzeugwerke. The very first exemption from this rule was granted several years later to Blohm & Voss when they renamed their aircraft manufacturing operation – which had been split off from Hamburger Flugzeugbau (Ha) – to Blohm & Voss and received the designation BV for their new aircraft, the first of which was the BV 138 Fliegender Holzschuh maritime patrol trimotor flying boat.

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