The Avro 504 was a two-seater biplane British of the First World War. It was manufactured by the manufacturer Avro and it was primarily used as a training aircraft for the training of the pilots but also, to a lesser extent, as a hunter.

Avro 504 accomplished its first flight, been driven by an engine Gnome-Lambda with 80 ch., in July 1913 with Brooklands.

In 1914, Avro accepted War Office a bearing contract on 12 apparatuses of type 504. Individuals showed themselves also interested by this plane and from many additional orders had placed to the manufacturer.

Avro 504 had the unhappy privilege to be the first British plane to be cut down on mission of war. It was the August 22nd 1914, above the Belgium, by weapons of Infanterie. The November 21st 1914, four Avro 504 of the British navy took part in the famous attack of the factories of Zeppelin S with Friedrichshafen. One of the planes was lost during this mission.

Versions

68 specimens of the initial version of the " 504" were manufactured. They were followed many other versions:

• 504A : similar to the basic model - 1  485 specimens were manufactured including 685 by Avro.

• 504B: version for the British Naval Aviation (RNAS) with a larger control surface and a modified tail skid (1 specimen was equipped with a Crosse of landing for tests on ships) - 250 specimens were built, including 60 by Avro.
• 504C: single-seat version for the RNAS intended to be used like patrol craft and for defense against the Zeppelins - 80 specimens were built, including 30 by Avro
• 504D: version intended for the Royal Flying Body (RFC) - 6 specimens manufactured.
• 504E: different motorization - 10 specimens manufactured.
• 504H: version 504B with the structure reinforced in order to be able to be catapulted starting from ships.
• 504J: motorized like the version 504E, it is starting from this model which the legendary career of Avro 504 as a plane of drive began. From 1917, Avro accepted a considerable number of orders of this version which was equipped either with the engine " Rhône" maybe of the engine " Gnome mono soupape" of 100 ch. - 2  000 manufactured specimens, of which 1  350 by Avro.
• 504K: like few specimens of the " 504" were employed as a fighter, the orders for the engine envisaged initially were reduced and this involved delays in the deliveries. Avro then adapted the airframe to be able to receive various engines and these models accepted designation " 504K". Engines Trulin, Gnome, Curtiss, Sunbeam, Bentley, Wasp and Hispano Suiza were used. These planes were used during many tests carried out by the Royal Aircraft Establishment with Farnborough and more than 300 planes of this type were used until in the years 1930 by private individuals. They are only whereas the " 504K" were replaced by the series of the " Moth" company De Havilland Aircraft Company and by the Avro Avian. Total production of the " 504K" 6  reached; 175 apparatuses of which 1  650 manufactured by Avro.
• 504L: Seaplane in three places, equipped with an engine Bentley - B.R.1 with 152 ch. (112 kw). This version was used only by the civil aviation and, on the whole, 17 specimens were manufactured, including 7 by Avro.
• 504M: modification of a " 504K" by the addition of a cabin and the installation of an engine " Gnome" 9 cylinders mono valve of 100 ch. (74 kw). It was manufactured during the summer 1919.
• 504N (also named Avro-Lynx or Avro 504N Lynx): before 1925 the ministry for the British air placed an order to Avro for a model named " 504N". Two apparatuses were tested, one equipped with an engine " Lucifer" Bristol-board; of 102 ch. (75 kw), the other with an engine " Armstrong Siddeley Lynx" of 182 ch. (134 kw); one finally retained the engine Lynx which is at the origin of the denomination Avro Lynx given to the " 504N". Many specimens of " 504K" , which had become available after the end of the First World War, were transformed into " 504N". The most visible modification, beside the more powerful motorization, was the train of bearing as well as a modified control surface. Almost 80 " 504K" were transformed into version " 504N". Many " 504N" were also exported, they in particular were sold with the Belgian air force (17 specimens), with the Brazilian Naval Aviation (4 specimens), with the Chilean Naval Aviation (6 specimens named " 5040"), with the Greek Naval Aviation (6 specimens), with the air force inhabitant of Thailand (20 specimens) and of unspecified number with the South-African air force . Single specimens were also delivered to the air forces of the Denmark, the Sweden and the Japan. On the whole 592 specimens of the " type; 504N" were manufactured, including 555 by Avro.
• U-1 Avrouchka : 737 specimens of Avro 504 were manufactured in Russia under license under this denomination.
• 504Q: some manufactured specimens, unknown technical data.
• Avro 504R Gosport: 28 apparatuses, probably intended for the Argentinian air force , were manufactured by A.V.Roe and Co Ltd, and 34 specimens of this type were manufactured by the Fabrica Militar de Aviones in Argentine.

Until the end of the First World War in November 1918, more 8  000 specimens of version 504 with 504K were thus manufactured, including 3.424 by Avro. The other manufacturers, who built these planes under license, were Brush Electrical, Parnall, Saunders, Blériot and SPAD. It should be noted that other sources quote 3.696 apparatuses manufactured by Avro.

The version " 504N" was manufactured under license only with some specimens in Belgium and with the Denmark.

" Vickers Canada" several " transformed; 504K" in " 504N" and also some " manufactured; 504N" (of which a seaplane) under license.

The " types; 504K" and " 504N" delivered to the Japan (a specimen of each) were modified in this country and were been driven by Japanese engines. Apparatuses of this type were manufactured there until in 1940.

In 1932 RAF named officially the Avro Tutor as a successor of the " 504N" and, in 1933, this last was definitively abandoned by the army. Nevertheless, in 1940, seven " 504N" civilians requisitioned by the RAF took again service. Two of these apparatuses were destroyed in a fire and two were put at scrap prematurely. The three remaining planes were used to tow sailplanes above the sea in order to be used as target with observers Radar.