The Royal Naval Air Service (RNAS) was the air arm of the Royal Navy, under the direction of the Admiralty's Air Department, and existed formally from 1 July 1914 to 1 April 1918, when it was merged with the British Army's Royal Flying Corps to form a new service, the Royal Air Force, the first of its kind in the world.During its first year it continued to be the Naval Wing of the joint Royal Flying Corps (which had been set up in 1912), but was administered by the Admiralty's new Air Department, but on 1 August 1915 the RFC became the flying branch of the British Army while the RNAS became "an integral part of the Royal Navy".