Editing Avro 504 (section)

==Variants==
[[File:Aviation in Britain Before the First World War RAE-O572.jpg|thumb|Early 504 with 80 horsepower [[Gnome Lambda]] engine]]
*'''504''': {{convert|80|hp|kW|abbr=on}} [[Gnome Lambda]] engine.
:Original model
*'''504A''':
:Modified with smaller ailerons and broader struts. {{cvt|80|hp}} Gnome engine.
*'''504B'''
:Version for RNAS with larger fin. {{convert|80|hp|kW|abbr=on}} Gnome or [[Le Rhône]] engine.
*'''504C'''
:Single-seat anti-[[zeppelin]] aircraft for the [[RNAS]]. The 504C was fitted with an extra fuel tank, in place of the observer.
*'''504D'''
:Single-seat anti-zeppelin aircraft for the [[Royal Flying Corps]]. Six built.
*'''504E'''
:{{convert|100|hp|kW|abbr=on}} [[Gnome Monosoupape]] engine. Ten built.
*'''504F'''
:{{convert|75|hp|kW|abbr=on}} [[Rolls-Royce Hawk]] engine. One built.
*'''504G'''
:Two-seat weapons training variant of the Type 504B for the RNAS. The Avro 504G was intended as a bombing/gunnery trainer, with provision for a Scarff ring mounted on the upper longerons, though the final ten delivered had no provision for a gun. Fitted with one 80 hp Gnome powerplant. 50 built and delivered between June 1917 and January 1918. 30 built by Avro and 20 constructed by The Regent Carriage Company.
*'''504H'''
:504C modified for catapult trials. 80&nbsp;hp (60&nbsp;kW) Gnome engine.
*'''504J'''
:504A modified to mount a {{convert|100|hp|kW|abbr=on}} Gnome engine.
[[File:First aeroplane in Iceland.jpg|thumb|This Avro 504K was the first aeroplane in Iceland, taken there in 1919]]
*'''504K'''
:Two-seat training aircraft. The 504K had a universal mount to take different engines. Single-seat fighter ('''Comic''') conversion used for anti-zeppelin work. Several were assembled in Australia by [[Australian Aircraft & Engineering]].<ref name="Wilson">{{cite book|last1=Wilson|first1=Stewart|title=Military Aircraft of Australia|date=1994|publisher=Aerospace Publications|location=Weston Creek, Australia|isbn=1875671080|pages=216}}</ref> {{convert|130|hp|kW|abbr=on}} [[Clerget 9B]], {{convert|100|hp|kW|abbr=on}} [[Gnome Monosoupape]] or {{convert|110|hp|kW|abbr=on}} [[Le Rhône 9J]] engines.
[[File:Avro Dyack used by QANTAS ca. 1921.jpg|thumb|[[Qantas]] 504K [[Sunbeam Dyak|Dyak]] (c. 1921)]]
*'''504K Mk.II'''
:Hybrid trainer based on 504K fuselage with 504N undercarriage and wings and powered by rotary engine. Built under licence in Mexico as '''Avro Anahuac'''.<ref name="Jackson avro p105">Jackson 1990, p.105.</ref>
*'''504L'''
:Floatplane version. {{convert|150|hp|kW|abbr=on}} [[Bentley]] BR1, {{convert|130|hp|kW|abbr=on}} Clerget or {{convert|110|hp|kW|abbr=on}} Le Rhône engines.
[[File:Avro504L1920.jpg|thumb|504L floatplane (1920)]]
*'''504M'''
:Three-seat cabin biplane. Only one was ever built. {{convert|100|hp|kW|abbr=on}} Gnome engine.
*'''504N'''
:Two-seat training aircraft. Redesigned postwar trainer for RAF with {{convert|160|hp|kW|abbr=on}} [[Armstrong Siddeley Lynx]] engine. 598 built.
[[File:Avro504n left.png|thumb|504N left side view]]
*'''504O'''
:Floatplane version of 504N. First aircraft to fly above the [[Arctic Circle]] in 1923 Oxford Expedition.
*'''504P'''
:Unbuilt version of the 504N with side-by-side seating.<ref name="Jackson Avro p127">Jackson 1990, p.127.</ref>
*'''504Q'''
:Three-seat cabin biplane. The 504Q was built for the Oxford University Arctic Expedition. Only one was ever built, powered by an [[Armstrong Siddeley Lynx]] engine.
*'''504R Gosport'''
:Reworked trainer with revised, lightweight structure. Five prototypes flown 1926 to 1927 with various engines (100&nbsp;hp/75&nbsp;kW Gnome Monosoupape, 100&nbsp;hp/75&nbsp;kW) [[Avro Alpha]], (140&nbsp;hp/104&nbsp;kW) [[Armstrong Siddeley Genet Major]] and (150&nbsp;hp/110&nbsp;kW) [[Armstrong Siddeley Mongoose]]), with the Mongoose chosen for production aircraft. Ten were sold to Argentina, with 100 more built by [[Lockheed Martin Aircraft Argentina|FMA]] under licence in Argentina. Twelve were exported to Estonia, remaining in service until 1940, and an unknown number to Peru.<ref name="Jackson Avro p129-33">Jackson 1990, p. 129-133.</ref>
[[File:Avro 504R Gosport with Avro Alpha motor NACA Aircraft Circular No.49.jpg|thumb|504R Gosport]]
*'''504S'''
:Two-seat training aircraft. Built under licence in Japan by [[Nakajima Aircraft Company|Nakajima]].
*'''540'''
:Observer training version of 504K for Japan.
*'''582'''
:Experimental version of 504N, with new wings of RAF 30 aerofoil section, Frise ailerons on the bottom mainplanes, wing struts reduced to a "K" arrangement and a simplified undercarriage. Converted back to 504N standard in 1928 for Bristol Titan engine test bed.
*'''585'''
:504R modified with 504N undercarriage and {{convert|90|hp|kW|abbr=on}} Avro Alpha engine.
*'''598 Warregull'''
:Two-seat trainer based on 504N for Australia, not built.
*'''599 Warregull II'''
:Redesigned version of Type 598, not built.
*'''Yokosuka K2Y1'''
:Japanese version of the Avro 504N, given the long designation '''Yokosuka Navy Type 3 Primary Trainer''', powered by a {{convert|130|hp|kW|abbr=on}} [[Mitsubishi]]-built [[Armstrong Siddeley Mongoose]] radial piston engine, 104 built.
[[File:Yokosuka K2Y 1938.jpg|thumb|Yokosuka K2Y (1938)]]
*'''Yokosuka K2Y2'''
:Improved version of the K2Y1, powered by a {{convert|160|hp|kW|abbr=on}} [[Gasuden Jimpu 2]] radial piston engine. 360 built (K2Y1 and K2Y2).<ref name="Mikesh p276">Mikesh and Abe 1990, p. 276.</ref> Watanabe built aircraft were given the long designation '''Watanabe Navy Type 3-2 Land-based Primary Trainer'''.
*'''U-1 (Uchebnyi – 1)''' ''Avrushka''
:Russian copy of the 504K. Over 700 built.<ref name="Jackson Avro p104">Jackson 1990, p. 104.</ref><ref name="BAE Systems" />
*'''MU-1 (Morskoy Uchebnyi – 1)<ref name="BAE Systems" />'''
:Russian seaplane version.
*'''Orlogsværftet Flyvemaskineværksted LB.I''' – Danish production at the [[Orlogsværftet|Royal Naval Dockyard]] (''Orlogsværftet'')<ref name="danish">{{cite web |title=DANISH AIRCRAFT MANUFACTURE |url=http://www.ole-nikolajsen.com/DANISH%20MILITARY%20%20AIRCRAFT%20PRODUCTION.pdf |website=ole-nikolajsen.com |access-date=29 December 2018 |location=Copenhagen |archive-date=15 August 2021 |archive-url=https://web.archive.org/web/20210815194359/http://www.ole-nikolajsen.com/DANISH%20MILITARY%20%20AIRCRAFT%20PRODUCTION.pdf |url-status=dead }}</ref>
*'''I1A'''
:[[Brazilian Navy]] designation of the 504K.<ref name=":0">{{Cite web |title=Brazilian Military Aircraft Designations |url=https://designation-systems.net/non-us/brazil.html |access-date=2025-03-16 |website=designation-systems.net}}</ref>
*'''I2A'''
:Brazilian Navy designation of the 504N and 504O.<ref name=":0" />
*'''B.F.4'''
:({{langx|th|บ.ฝ.๔}}) [[Royal Thai Air Force|Royal Siamese Air Force]] designation for the 504N.<ref>{{Cite web |title=Thai Military Aircraft Designations |url=https://designation-systems.net/non-us/thailand.html |access-date=2025-03-18 |website=designation-systems.net}}</ref>