<P> The Royal Navy at the start of the war was the largest navy in the world due, for the most part, to the Naval Defence Act 1889 and the two - power standard which called for the navy to maintain a number of battleships such as their strength was at least equal to the combined strength of the next two largest navies in the world, which at that point were France and Russia . </P> <P> The major part of the Royal Navy's strength was deployed at home in the Grand Fleet, with the primary aim of drawing the German High Seas Fleet into an engagement . No decisive victory ever came . The Royal Navy and the German Imperial Navy did come into contact, notably in the Battle of Heligoland Bight, and at the Battle of Jutland . In view of their inferior numbers and firepower, the Germans devised a plan to draw part of the British fleet into a trap and put it into effect at Jutland in May 1916, but the result was inconclusive . In August 1916, the High Seas Fleet tried a similar enticement operation and was "lucky to escape annihilation". The lessons learned by the Royal Navy at Jutland made it a more effective force in the future . </P> <P> In 1914, the navy had also formed the 63rd (Royal Naval) Division from reservists, and this served extensively in the Mediterranean and on the Western Front . Almost half of the Royal Navy casualties during the War were sustained by this division, fighting on land and not at sea . </P> <P> At the start of the war, the Royal Flying Corps (RFC), commanded by David Henderson, was sent to France and was first used for aerial spotting in September 1914, but only became efficient when they perfected the use of wireless communication at Aubers Ridge on 9 May 1915 . Aerial photography was attempted during 1914, but again only became effective the next year . In 1915 Hugh Trenchard replaced Henderson and the RFC adopted an aggressive posture . By 1918, photographic images could be taken from 15,000 feet (4,600 m), and interpreted by over 3,000 personnel . Planes did not carry parachutes until 1918, though they had been available since before the war . On 17 August 1917, General Jan Smuts presented a report to the War Council on the future of air power . Because of its potential for the' devastation of enemy lands and the destruction of industrial and populous centres on a vast scale', he recommended a new air service be formed that would be on a level with the army and navy . The formation of the new service however would make the under utilised men and machines of the Royal Naval Air Service (RNAS) available for action across the Western Front, as well as ending the inter-service rivalries that at times had adversely affected aircraft procurement . On 1 April 1918, the RFC and the RNAS were amalgamated to form a new service, the Royal Air Force (RAF). </P>

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