In July of the previous year (1912) Lieutenant Raymond Fitzmaurice, R.N., had been appointed for wireless telegraphic duties with the Naval Wing. At that period he was unable to obtain from English manufacturers ‘a light and compact alternator which could be run off the main engines of the aeroplane’. In the same year, however, the engineer to the Eiffel Tower wireless telegraphic station in Paris (M. Lucien Rouzet) designed and built a transmitting apparatus which, in proportion to its power, was lighter in weight than any which had been previously in use*, and Fitzmaurice obtained permission from the Admiralty to go to Paris in order to Paris in order to see the set. Later he bought a few of these instruments which gave good service. The first trials with them were conducted from a machine flying over Dover, and they proved a success, for signals were received clearly up to a distance of twenty miles. The principal difficulty which Fitzmaurice experienced at this period ??as due to the entire lack of knowledge on the part of the aeroplane makers in things w/t, and it became necessary to get the Admiralty to put w/t requirements into the original specifications for its machines and to go round personally to every Admiralty contractor and explain that a machine built originally without a view to taking w/t was often impossible to fit with w/t after delivering??
At the end of the trials Fitzmaurice decided, for the time being, to give up the idea ‘of reception in aeroplanes, as the roar of the engines and the vibration of the machine made it impossible to receive with any known receiving apparatus, and there was plenty to do in the meantime in developing transmission’. Not until some two years later were the difficulties of reception on their way to solution.
These experiments with-wireless telegraphy were of particular value because the Admiralty had decided that aircraft should take part in the naval manoeuvres (which were to be held in July 1913) in order to determine their value for the purposes of reconnaissance.
*The Rouzet apparatus consisted of a self-exciting alternator of 1/4 k.w.; an air-cooled transformer which ‘stepped’ the current of the alternator up from 110 to 30,000 volts; a spark-gap of a design which emitted a clear, musical note; a tuning coil (primary and secondary) for altering the wave-length; a reel for letting down and raising the aerial; a signalling key, safety cutter, and clutch for clutching the alternator in and out from the main engine of the aeroplane. Depending upon the wavelength used, from 100 to 400 feet of aerial wire was released, the weight (1 lb.) on the end keeping the trailer clear of the machine. A single wire stretched from the upper plane to the tail in the form of a triangle was used as the earth. A detailed description of the apparatus is given amongst the series of articles; ?? History of the Development of Aircraft Wireless, Aeroplane, 1, 8, 15 and 22 September, 1920.
Ref The Air Weapon, Vol 1, CF Snowden Gamble, pp216-7