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List of conversion units of the Royal Air Force

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General referenceInterpretive dossier study · Crown Archives visual atlas
Record originEnglish Wikipedia
Text licenseCC BY-SA 4.0
Source revisionApr 22, 2026
Entity authorityQ6595944 ↗
Source-derived summary

Conversion units and operational conversion units (OCUs) were training units of the Royal Air Force (RAF).

History

With the introduction of new heavy bombers, the four-engined Short Stirling, Avro Lancaster, and Handley Page Halifax, the Royal Air Force introduced heavy conversion units (HCU). These HCUs began forming in late 1941, to qualify crews trained on medium bombers to operate the heavy bombers before final posting to the operational squadrons. Some of the HCUs were involved in bombing operations over Germany.

After the end of the Second World War, the role of the HCUs was taken over by the operational conversion units (OCUs). Although the units had nominal bases, different flights and individual aircraft usually were detached nearer the operational bases.

RAF OCUs are training units that prepare aircrew for operations on a particular type or types of aircraft or roles. Some OCUs have a shadow, or reserve, squadron designation, which is used if the unit has a war role.

Current RAF OCUs

F-35 Lightning – RAF Marham

207 Squadron

Typhoon – RAF Coningsby

29 Squadron

Support helicopter (Puma and Chinook) – RAF Benson

28 Squadron

Air Mobility (Atlas and C-17) – RAF Brize Norton

24 Squadron

ISR (Wedgetail, Poseidon) – RAF Lossiemouth

42 Squadron

ISR (Reaper, Protector, Rivet Joint and Shadow) – RAF Waddington

54 Squadron

Some aircraft types operated by a single squadron, which includes most transport aircraft, and most ISTAR aircraft, are not big enough to need a dedicated OCU squadron for their training requirements; they may only have a few at any time. Therefore, smaller squadrons also incorporate training facilities to allow them to process aircrew onto their aircraft type.

Editorial summary

“List of conversion units of the Royal Air Force” enters the record as wikimedia list article. Crown Archives preserves that source wording while asking what List, conversion and units can confirm, complicate or overturn.

Editorial reviewA practical starting point whose main value is the path it opens into stronger specialist and primary sources. The current lead gives the account dated anchors—1941—that can be checked directly. The selected authority fields contribute no independent date. Its strongest next move is a source search built around List, conversion and units.
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Why this record matters

“List of conversion units of the Royal Air Force” is worth following because a concise public description often conceals a longer documentary argument. Here, List, conversion and units provides the most credible route into that argument.

Evidence profile

The citation trail is more important than the brevity of the summary: it shows where individual claims can be examined in context. The source revision retrieved here is dated Apr 22, 2026. The linked authority identifier is Q6595944. None of the 0 selected statements returned an explicit reference. The first chronological checks are 1941.

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Source & attribution

This entry incorporates text from “List of conversion units of the Royal Air Force” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.