AVIATION NOTES

Rotorua Morning Post, Volume 1, Issue 100, 18 December 1931, Page 2

AVIATION NOTES

"Aileron".

PROBLEMS OF DESIGN Speciall written for the "Post"

by

• The great strides that have been made in aviation in reeent -years are certairily fulfilling the predictfons of many enthusiasts in the early days of flying. "Ha;d it not been for the disturbing influence of the war there is no doubt that, by this time we should have arrived at much higher staridard of5 design. Certainly we would not hhve the engine - efficifency, but aircraft designers would have passed the stage at whiclr'they have arrived to-day. AWay jback in the year 1910, when the art- of flying' was in its infhncy, A. V. Roe, the well known constructor, delivered a lecture in England on the subject and his title for his address was "Can we fly faster with less power." In the' course of his address he dissected every then known cross section of ' 'supporting surface. " 'At that • time designers were also faced by another problem. Could they fly faster with the same power, the maximum" ' power available, heing ahout 80 h.p. in the tried-out engines of the dajr. By the year 1912 speeds were beginning to creep up and in that year the Gordon-Bennett Cup was won by C.' G'raha'm-'W'hite at a speed of seventy miles an hour. In thei same year the military trials were held in England and the conditions laid down were condueive to the production of a sound all- round aeroplane. • This competition was won by a perhaps antiquated design even' at that time, but the Bristol monoplane, which was placed second was-very little beHihd, if not "equal-to our light 'planes of the1 present day. • Th.e conditions under which the competing machines flew were Very severe and landings had to be mafle on freshly ploughed ground sometimes across the furrows according"'to the direction bf ' the wind. Engine Failure In many cases very clever productions were put out of the competition by engine failure, and details such as magneto drives, -failure of petrol pipes, and other minor 'defects rather than break-downs in'the power plant itself were responsible. About this time Glen Curliss in America succeeded in getting a seap'lalie olf thfe water, and a new era in fl^iiig was opened, which ;to'-day remains the most neglected branch of flying ^pxcept for machines in the naval, military, and the larger class of passenger serviees. In the year 1913 the Sehneider Contest was inaugurated and being open to international competition has at various times been very keenly conte'sted by various nations, until it was wori outright hy Great Britain this year. ^ Onc of the outstanding victories in this 'race, in fact the only one which showed a remarkable improvement in aeroplane design over the previous c.ompetitors, Was w'hen Italy retained the tvophy in 1921. The speed attained in the previous year was 107 miles an hour, at an expenditure of over five h'undred horse power, while in the 1921 contest a speed of 111 miles' ari* hour was attained with an exp'enditure of ohly two hundred horse power. Iiad this improvement in design been earried on to the present day we should certainly have been able to run unsubsidised air lines. The wonderful strides made in aero engines during, and after- the war have been to a great extent the tindoing of the aeroplane from a point cf cheapness and efficiency. Speeds of engines have iricreased to such an extent that to get anything like a good trarisfer of power by medium of the propellor, reduction gearing has to be nsed' which ' again adds to the cost of production. Engine Type Needed Slower speed — we cannot say more reliable engirles and 'more efficient planeS — would place the aeroplane in a "class with the present motor car. In the first successful aeroplane to fly the efficiency of the propellors was twelve and a half per cent better thaii' 'thdse used in this year's Schheidei" Tfophy • machines. Apart ' from the- point of Mtilisation of the power available in either case these machines cannot be compared any more than can a racing car to a passenger bus. Tn our larger passenger and commercial aeroplanes, constructors have not' Been in 'any maner to blame. It has just been -a- combination of circumstances, mainly brought about by the "war," that has made production sb costly. The iric'ompatible stipulations at yafious t'imes placed on constructional methods have rather tended to keep Great Britain behind other nations ° in - 'the" evolution of various types of aircraft. ""Welded j'oirits were not allowed alth'ough • used in other countries for years, while at the same time stressete of five thousand pounds to the square irich were 'allowed 'in spruce, the'-tim-ber most in favour in wooden structures. While our constructors were foreed to'make forgings, and flnish them on expensive machines, in the Fokker works steel tuhes were cut into suitable lengths, the ends trimmed to a fit with a pair'of tinmeii's snips and a finished welded joint made in a few minutes. • This class • of structure is noiy looked'on favourahly by the Air Ministry and allowed after ' being used with success for years in othef countries. The tendency of the controlling body, the Air Ministry, has been to push the industry forward with one hand and phll it back with the other. In the motor car industries, without any' governmeht interference regarding road worthiness, firms have produced in' every case a vehicle with enorm'ous factors of safety; if left alone aircraft constructors -would do 'the same ahd 'the A.I.D. could confirie itsself to the inspection of passenger aircraft. What is wanted to-day is siiiiple, reliable, "and cheaper aifc'raft which" can ' fly faster ahd slower witk the same power.