Avro 504N and O

For a description of the format and data included in Production Tables, see here.

For description of Types 504N and O see Production Summary

Production Tables Index

Type 504N - Development and Intermediate Aircraft
Type 504N - UK Built Delivered As Military
Type 504N/O - UK Built For Export As Military
Type 504N/O - UK Built Delivered As Civil
Type 504N - Non-UK Built Delivered As Military
Type 504N - Non-UK Built Delivered As Civil

Notes

1. This was a series of aircraft used in the integration of various radial engines into the Type 504 airframe in place of the rotary, along with the development of an entirely new undercarriage that came to symbolize the Type 504N. Non of these can be considered a fully developed Type N.
2. Jackson [1] defines these four aircraft as an advanced interim type with oleo sprung skid-type under carriage, but photograhic evidence [13] shows at least G-EBHC, which lasted only a month before crashing, was a fully developed 504N.
3. Fitted with a 200 h.p. Wright J-4 powerplant. The one aircraft built was initially a single float seaplane, later converted to a landplane with Wright J-5. RCAF designations were Avro Wright Seaplane (A.W.S.) and Avro Wright Landplane (A.W.L.). A further six were to have been ordered in 1925, two seaplanes and one land plane, but the order was never placed.
4. Fitted with 180 h.p. Armstrong Siddeley Lynx IVC powerplant. First three were built as seaplanes, using the same single float design as the Type 552A, were delivered in January 1928, this being followed by nine landplanes delivered in February 1928. The floatplane version was designated Avro 504NS in the RCAF.
5. G-ACZC, registered October 1934, was possibly a rebuild of G-ACRS, which crashed 6/34. both are shown with the same military serial.
6. G-ADEV impressed as BK892 under file contract SB.7560/E1. To Instructional Airframe 3118M then the Shuttleworth Collection as G-ACNB in October 1981 and reconverted to Type 504K. Registration restored to G-ADEV in April 1984 but carries military serial E3404.
7. G-ABVC given in G-INFO as ex F8841, but this was 504K supplied to Argentina. Jackson [1] and LAAS [9] indicates ex F8834, which would make it a 504K converted to a 504N. Vic Smiths Accident report [10] also shows as 504N.
8. Known locally as Avro 504K Lucifer, these were fitted with 100 h.p. Bristol Lucifer powerplants.
9. Note that the Avro 504K displayed in the Canadian Aviation and Space Museum as “G-CYFG” is not in fact that aircraft, but its provenance is worth recording. The following from the CASM website [20]:
   "Manufactured by Avro in England 1918 (Mfr. No. A958), RAF registration H2453; Frank F. Valcourt, Pawtucket, Rhode Island, U.S. civil registration #5918, fitted with LeRhone engine 1928; Rooseveldt Field Museum, early 1930’s;
   J.H.C. Palen, Rhinebeck, N.Y., U.S. civil registration N8736R 1951 (used for flying displays U.S. and Canada);
   Purchased by RCAF, delivered Trenton, 19 May, 1966;
   Rebuilt 6 RD Trenton (Crew Chief MWO H. Tate) 1966-1967, TOS 1 June 1966;
   Assembled Rockcliffe, Clerget engine from National Research Council of Canada (NRCC) installed 12 Dec., 1967;
   Now on display at CASM, equipped with Turnbull Variable-pitch Propeller. Note: 504K, RAF registration H9555, originally assigned Canadian registration “G-CYFG,” TOS May 1924, converted to 504N 24 July 1927, SOS 30 May 1930. "
   How H2453 came to be in the US originally is unclear.
10. Alberto Fernandez Donoso and Ray Sturtivant [6]: "Avro supplied six 504-Os (C/n 355 to 360) to the Chilean Navy, these being modified versions of the 504N, given the Chilean serial numbers 82 to 87 inclusive and probably assembled in Chile." The same reference has a photograph of an Avro 504O '19' of the Chilean Navy converted to a landplane.
    The article then summarises as follows:
    1929 6 Avro 504-O 82 to 87 (c/n's 355 to 360) seaplanes for Navy, deld 8.29. One later as landplane "19".

    Dan Hagedorn [7]: ""Regarding the alleged Chilean Navy Avro 504Os delivered in August 1929, I must confess to being puzzled by the "high" serials quoted (e.g. 82 to 87). Try as I may, I cannot come up with any reason why the Navy should have had serials such as these at that particular date. The photo accompanying this statement, on page 7, of Chilean Navy 504O serial "19" further confuses me! I must agree, however, that 19 seems a much more reasonable serial number for a Navy aircraft at that date.""

    George A. Jenks [7]: "There appears to be confusion about the Avro 504Os: Avro supplied seven a/c in early 1927, serialled 15 to 21 inclusive. These were all tested with wheels at Woodford (whence the photo of No. 19) before going to Hamble for the fitment of floats prior to delivery. These machines probably bore constructors numbers in the range R3/AV/- for which no complete listing seems to have survived. They were probably supplied with both sets of undercarriages, as Jane's 1927 quoted the Chilean Navy as using "Avro lynx land or sea machines". A further batch of six aircraft were supplied in 1929 bearing the c/ns 355 to 360 and serialled 82 to 87 respectively. However, the first serial number conflicts with the last 504K . . ."

    Dan Hagedorn [8]: "Four 504Ns, frequently cited as going to the military circa 1925 (E444, H2512, H2562 and F8841), seem more likely to have been sold to civilian users, as no evidence has emerged to support EMA or Aviacion Militar use."

    Rivas [22] gives them as having serials 15 to 21 on arrival, but changed almost immediately to 75 - 81. All transferred to the Army in July 1930. These were then followed by another 6 in 1929 with serials 82 to 87.

11. Export Type 504Ns and 504Os were either supplied in mixed batches or as 504Ns with optional floats, hence for this site this author will use the term Type 504N/O.
12. C/ns 439-442, plus 2 others, per Jackson [1]; c/ns 441-446 per Rivas [22], but that would clash with Avian c/ns.
13. From Ionnis Mylonas, ex Hellenic Airforce Museum (via e-mail):
    "Six Avro 504N/504Os were supplied in 1925 to Works Order 7787 for training schools at Tatoi and Phaleron Bay of Hellenic Naval Air Service Avro C/ns unknown.
    Presumably the aircraft received the code Nos or Serials 133, 134, 135, 137, 138, 139 four of them confirmed by existing photos, while 133 and 139 was lost 01/10/1925 and 08/03/1928 respectively at Phaleron Bay both as sea planes.
    Also, the same period (1927-29), 24 new aircraft was built according a six-page report compiled by KEA director G.W. Cannell to Robert Blacburn dated 2Feb. 1931, that been: 15 Avro Lynx and 9 Avro Mongoose.
    According to report by Blackburn Aircraft Ltd., Publicity Department dated 17Aug. 1944 New Avro 504N Landplanes and Avro 504O Seaplanes was built both with Lynx IVC 215HP engines, with no number specified."

    This is further qualified by Lennart Andersson, via posts on the Air Britain Information Exchange (AB-IX) forum, December 15, 2015:
    "According to my notes (from Foreign Office files in London and other sources) the Kratiko Ergostasio Aeroplanov/National Aircraft Factory built
    12 Avro 504N/O, 1931
    10 Avro 504N/O, 1935"

    Grant [24] states "In 1930, Greek naval aviation purchased $534,600 (£110,000) worth of air equipment from England, and the next year bought ten Fairey lllF seaplanes and twelve Avro 504N aircraft." This would appear to refer to engines and components required for Greek production.

    So this gives either 22 or 24 Type 504N/Os built by the EAF; I choose to go with the 22 as these are seemingly qualified by an FO report.

    Finally, regarding the serials of the Greek Naval aircraft; initially the service used the British serial, but by January 1921 this had changed to the NAYXXX format. (NAY = Naftiki Aeriporiki Ypiresia/Naval Air Service). From 1923 onwards the coding was changed to EaXXX for training aircraft (E = Ekpedeftiko/Training), this being changed again in January 1931 when the unification of the two services took place and the Hellenic Air Force was created, dropping the "a" to EXXX which was retained until the entrance of Greece to the WW II.

Production References

1. Avro Aircraft Since 1908, A.J. Jackson (Putnam, 1965 and 1990)
2. Air Britain RAF Aircraft Serials, Various Volumes (Air-Britain Publications)
3. Canadian Aircraft since 1909, K.M. Molson and H.A. Taylor (Putnam, 1982)
4. Canadian Military Aircraft Serial Numbers at CASPIR (Canadian Aircraft Serials Personnel Information Resource) at the Canadian Warplane Heritage Museum
5. British Military Aircraft Serial, 1878 - 1987, Bruce Robertson (Midland Counties Publishing, 1987)
6. Air Britain Digest, 1989/1 (Air-Britain Publications)
7. Air Britain Digest, 1989/3 (Air-Britain Publications)
8. Air Britain Digest, 1990/3 (Air-Britain Publications)
9. British Isles Civil Aircraft Registers 1919-2011 (LAAS International, 2011)
10. http://www.orpheusweb.co.uk/vicsmith/OldAccs/Mar30.html
11. Insignia No.12 (Blue Rider Publishing)
12. Los AVRO 504 en Argentina y el método Gosport at https://www.histarmar.com.ar/AVIACION/EloyMartin/EO20c/E020c.pdf
13. http://www.edcoatescollection.com/ac5/ROW%20Europe/G-EBHC.html
14. Avro 504 in Swedish service at http://www.avrosys.nu/aircraft/MFV/064-Avro-504K/064-Avro504K.htm
15. Naval Aviation in Brazil at http://www.naval.com.br/anb/ANB-aeronaves/Avro_504_NO/Avro_504_NO.htm
16. http://www.airhistory.org.uk/gy/index.html
17. The British Roundel Mar/Apr 1998
18. The British Roundel Jan/Feb 1999
19. The British Roundel Jul/Aug 1999
20. https://documents.techno-science.ca/documents/CASM-Aircrafthistories-Avro504K.pdf
21. Avro 504 in Sweden at http://www.svfplhist.com/
22. British Combat Aircraft in Latin America, Santiago Rivas (Hikoki, 2019)
23. http://greek-war-equipment.blogspot.com/2010/10/1920-1936-avro-504.html
24. Between Depression and Disarmament: The International Armaments Business, 1919–1939, Jonathan A. Grant (Cambridge University Press, 2018)

 ... and many thanks to Ionnis Mylonas for all things Greek.