PRESIDENTIAL ADDRESS. 259 



be interchangeable, and ifc was necessary to maintain the highest quality with 

 the minimum amount of skilled labour. For a period the supply of magnetos 

 was both inadequate and unsatisfactory. The Germans had acquired practically 

 a monopoly in this direction, and it became essential for us to build up a new 

 industry on the results of careful research and experiment. The fact that under 

 these circumstances a total of eight million horse-power was produced during the 

 last twelve months of the war represents one of the greatest achievements of 

 engineering organisation. 



Synchronised gun firing through the propeller was first brought into use by 

 the enemy, and the success of the Fokker was due, not to superior design, but 

 to this characteristic armament and to the relatively high engine power. On the 

 other hand, throughout the war the only stable machines were British. For 

 observation work, night flying, and flight in fog and cloud the advantages of 

 a stable machine are obvious. On the other hand, in.^tability, inasmuch as it 

 favours rapid and unexpected manoauvres, was for a time regarded as an advan- 

 tage in aerial fighting, but later experience proved that a well-designed aeroplane 

 could be made stable and yet remain quick and light on the controls. 



Seaworthiness, no less than air-worthiness, is requiretl of the seaplane, and 

 this implies a machine of considerable size and weight. Most of the best sea- 

 planes in use in 1918 had a total weight of four or five tons each, a speed of nearly 

 100 miles, and engines of about 700 horse-power. 



The machines used by the special aeroplane ships were principally small fast 

 scouts, but one type was of sufficient size to carry an 18 in. torpedo. In 1918 

 seventy aeroplanes were carried by the fleet as part of the regular equipment. 



Airships proved to be of great importance in connection with naval work. 

 The smaller non-rigids were used for patrol duty along the coast and convoy 

 service, and by their- means a submarine could be detected and attacked while 

 still at a considerable distance below the surface. The success achieved w^as 

 extensive, and ships convoyed by airslrips were practically immune from sub- 

 marine attack. The larger non-rigids served as scouts in naval operations. 



The SSZ had a speed of 50 miles and a gross lift of about 2 tons ; the North 

 Sea type a lift of 11 tons and a speed of 60 miles. 



Compared with the achievements in other directions the record of British 

 work in connection with the development of rigid airships is not entirely satis- 

 factory. In this fi.eld, where consistent policy and firmness of purpose were 

 essential, the Admiralty vacillated strangely. The May-fly, constructed at 

 Barrow in 1910, was admittedly an experiment, and although an accident ended 

 her career after the first few mooring tests, she had already served her purpose 

 in providing the experience and data necessary for a more perfect construction. 

 Nothing further was done, however, until after the war had started. 



In Germany, on the other hand, painstaking plodding had built up success 

 on the ruins of a dozen failures. 



Improvements in the rate of climb of aeroplanes and the invention of the 

 incendiary bullet brought an end to the effectiveness of the Zeppelin as a bomber, 

 but as a scout in long range naval operations its influence remained considerable. 

 and the recent successful journey of R34 indicates the possibilities of the rigid 

 airship in times of peace. The useful load increases rapidly with size, and a 

 ship 15 per cent, larger than E34 in linear dimensions could have carried 

 100 people to America. 



What is popularly known as an invention, or an idea of revolutionary im- 

 portance emanating from one person, has played relatively little part in the 

 recent development of aeronautics. Success has been due to systematic investi- 

 gation and to the combined effort of many scientific workers, trained designers, 

 and practical constructors. With some exceptions the same holds true in the 

 case of engine construction. Inventions there have been, 8,000 are duly recorded 

 in the files of the Air Inventions Committee, but equipment and armament and 

 accessories appear to have offered most scope for brilliant new departures. 



Several inventions notably influenced the course of the war. The successful 

 manufacture of incendiary bullets put an end to the Zeppelin raids, tracer bullets 

 increased the accuracy of aim, and synchronising gear made it possible to fire 

 through the propeller at the rate of nearly 1,000 ixjundg per minute. A satisfac- 

 tory self -sealing petrol tank was manufactured after many unsuccessful attempts, 

 and greatly dinn'nished tlie risk- of fire. j\f n( h ingeiuiity was displayed in con- 



