The Royal Naval Air Service (RNAS) was first established in January 1914. By the outbreak of the First World War in August 1914, the RNAS had more aircraft under its control than the British Army's Royal Flying Corps (RFC). The main roles of the RNAS were fleet reconnaissance, patrolling coasts for enemy ships and submarines, attacking enemy coastal territory and defending Britain from enemy air-raids.
The leading RNAS WWI ace was Raymond Collishaw with 60 victories. On April 1, 1918 the RNAS, which at the time had 67,000 officers and men, 2,949 aircraft, 103 airships and 126 coastal stations, was merged with the RFC to form the Royal Air Force.