The airships _Delta_ and _Eta_ were both equipped with wireless for the army manoeuvres of 1913, and were based on Dunchurch, near Rugby. In all, _Delta_ sent sixty-six messages during her seven voyages, and on the 24th of September carried out a successful night reconnaissance. The _Eta_, owing to engine trouble, played no effective part in the manoeuvres, but during her journey from Farnborough to Dunchurch she maintained wireless communication with Aldershot till she reached Woodstock, when she called up Dunchurch and kept in communication for the remainder of the voyage. Captain Lefroy in his report says: 'It seems probable that H.M. Airships _Delta_ and _Eta_ can exchange messages with each other when 100 miles apart in the air, which may prove useful for organization purposes, &c. I received clear signals from the North Foreland station (and a ship to which she was talking) when 130 miles N.W. of it, and whilst H.M.A. _Eta_ was cruising northwards at touring speed.' Just before the 1913 army manoeuvres, Lieutenant B. T. James, piloting a B.E. aeroplane, succeeded in receiving wireless signals with the engine running at full power. To enable him to do this his machine was fitted with Captain Lefroy's new receiving set in which magneto disturbances were screened off and the signals strengthened by Brown relays, that is, microphones invented by Mr. S. G. Brown. In June 1914 Lieutenants D. S. Lewis and B. T. James flew from Netheravon to Bournemouth each in a B.E. aeroplane equipped with sending and receiving apparatus; they flew about ten miles apart, and kept in close communication with each other the whole way. Captain Lefroy continued to act as wireless expert to the Royal Flying Corps up to the outbreak of the war. The work done by him and by Lieutenant Fitzmaurice was of great value. When the war broke out wireless sets had been fitted to sixteen seaplanes, as well as to the two airships _Astra-Torres_ and _Parseval_, which did good service in patrolling the Channel during the passage of the Expeditionary Force.