The Avro 504, a lightweight, two-seater aircraft, was designed by Alliot Vernon Roe in 1913. It was an easy plane to fly and was used in the early stages of the war for light-bombing and reconnaissance missions. When a Avro 504 was shot down on 22nd August, 1914, it became the first British casualty of the war. Three Avro 504 were used to bomb the Zeppelin factory at Friedrichshafen. However, the Avro 504 was not a successful combat aircraft and they were withdrawn from the Western Front at the end of 1914.

A new version of the Avro 504B was produced early in 1915. This was a single-seater and this enabled the aircraft to store extra fuel and take part in long-range reconnaissance missions. It was also hoped that the Avro could be used against Zeppelins when they bombed Britain. This Avro was withdrawn from front-line action during the summer of 1915 and for the rest of the war was used as a training aircraft. A total of 8,340 Avro aircraft were built during the war and it remained in service as an RAF trainer until 1924.