FUTURE OF FLYING WIMPERIS 495 



required is such a degree of user as will call for this forai of aircraft 

 to be constructed in numbers. ^^Hien that happens, rotary-wing 

 aircraft will benefit in their design by that skilled attention from 

 the production engineer which alone seems able to produce results 

 that really look right. 



The growth in recent years of the interest taken by the public in 

 aviation, over land and over sea, is most striking. Partly, of course, it 

 is due to the increase in the Air Arm and all that is thereby implied. 

 But there is also a very rapidly growing use being made of the 

 abundant facilities for air travel offered by the civil air-transport 

 services. The United States is often thought to lead the world in 

 this respect — as it certainly does in the use of the automobile — ^but 

 I believe that in proportion to the size of the population, and that is 

 the true criterion, the total mileage flown annually is larger in Aus- 

 tralia than it is in any other single country in the world. And there 

 is good reason to expect that that preeminence is likely to continue. 



THE FUTURE YEARS 



Let us consider what lies ahead in the coming years in respect 

 of speed, size, and range. No doubt military craft will go as fast 

 as they can. But since it seems that they cannot exceed 600 miles 

 per hour much if at all, there is little doubt that speeds between 

 500 and 600 will become usual. Not so, however, for the civil air 

 services, where quiet, comfort, and cost are all-important. Here 

 there is good economic reason for speeds to settle down in the 200 

 to 300 range. In both these classes we seem therefore to be approach- 

 ing some degree of finality. 



Altitude and range are alike in that so much depends on the dis- 

 covery of new materials of construction and new ways of using them. 

 Steady progress may be expected, though probably nothing sensa- 

 tional unless the use of reinforced plastics be so reckoned. For civil 

 work the advantage of long-range flying depends on the ability to 

 fly by night, and this is advancing rapidly. Radio services are 

 improving and the vagaries of the ionosphere are becoming better 

 understood. High-altitude flying — w^iether in the stratosphere or 

 just below it — requires the sealed cabin, and it will, I fancy, chiefly 

 be sought by those whose first care is speed and whose lesser concern 

 is cost. 



When, however, we come to think of such other factors in the 

 future of flying as the size of the craft, and tlie wing loading em- 

 ployed, we are concerned with quite other considerations. Size 

 depends mainly on engine power, for there is a limit to the number 

 of power units which can be conveniently looked after. Even if we 

 have tractor and pusher airscrews in tandem (and tractor screws 



