"Avro" was short for A.V. Roe & Co., Ltd., of Manchester and Hamble. A. V. Roe's planes may have only played a small direct part in the history of WWI air combat, but the 504 played a larger part as a trainer, and of course (unlike many of its contemporaries) the Avro firm had a history lasting long after World War One. 8340 504s were produced during the war.
Aircraft from the Great War or shortly thereafter include:
- Avro 500 [note 1]
- Avro 504E [note 2]
- Avro 504F [note 3]
- Avro 504G [note 4]
- Avro 504H [note 5]
- Avro 504J [note 6]
- Avro 519 [note 7]
- Avro 521 [note 8]
- Avro 523 "Pike" [note 9]
- Avro 527 [note 10]
- Avro 528 [note 11]
- Avro 529 [note 12]
- Avro 530 [note 13]
- Avro 531 "Spider" [note 14]
- Avro 533 "Manchester" [note 15]
- Avro's first plane did not see combat, but the dozen 1912 biplanes were early trainers and started the train of Avro designs.
- Ten 504Es were built and used as trainers.
- The 504F was an experimental version with a 75hp Rolls-Royce Hawk engine. Production was not undertaken, as it was underpowered.
- The 504G was a gunnery trainer version of the 504B.
- The 504H was a converted 504C used in RNAS experimentation with catapult launches from ships.
- The 504J was a widely-used trainer which appeared in the autumn of 1916. Many were converted to 504Ks.
- Six larger prototype biplanes were built and sent to the RFC and RNAS, but the type did not enter production.
- Twenty-six two-seater fighters based on the 504 were built in 1916, but they were probably only used as trainers.
- The twin-engine 523 Pike showed promise in 1916, but it was not selected for production.
- The 527 was a failed two-seater prototype with a 150hp Sunbeam.
- The 528 was a 527 with a 225hp Sunbeam engine, but it was no more successful.
- The 529 and 529A were long-range bombers based on the Pike. They were tested in 1917 but were not selected.
- The 530 was a promising two-seater fighter, but a shortage of Hispano-Suiza engines and competition with the Bristol F.2B led to its shelving.
- The 531 was a compact and nimble single-seat fighter, but its low horsepower and single gun put it behind the times for 1918.
- The 1918 Manchester was a twin-engine bomber that came too late for the war, but its stats and size were similar to the Airco D.H.10.
- Bruce, p.36
- Bruce, p.53.
- Bruce'69, pp.34-37.
- Bruce, pp.39-55.
- Bruce'69, pp.56-58.
- Bruce'69, pp.58-59.
- Bruce'69, pp.59-60.
- Bruce'69, p.60.
- Bruce'69, p.61.
- Bruce'69, pp.61-63.
- Bruce'69, p.64.
- Bruce'69, p.66.
- Bruce'69, pp.67-69.