On 13 August 1914, 2, 3, and 4 squadrons, comprising 60 machines, departed from Dover for the British Expeditionary Force in France and 5 Squadron joined them a few days later. The aircraft took a route across the English Channel from Dover to Boulogne, then followed the French coast to the Bay of the Somme and followed the river to Amiens. When the BEF moved forward to Maubeuge the RFC accompanied them. On 19 August the Corps undertook its first action of the war, with two of its aircraft performing aerial reconnaissance. The mission was not a great success; to save weight each aircraft carried a pilot only instead of the usual pilot and observer. Because of this, and poor weather, both of the pilots lost their way and only one was able to complete his task.