AIRSHIPS.

Timaru Herald, Volume XIIC, Issue 13595, 15 May 1908, Page 7

AIRSHIPS.

It is not- clear what precise importance attaches to the cable messages that tho Wrgiht Brothers made a flight of 25 miles with one of ti..;r aeroplaues. In 1905 they claimed to have flown 24 1-5 niiks in 38 3sec—stating that the liight was then only stopped by exhaustion of fuel. This flight was made over a circular course, and the average speed was over 38 miles an hour. On a straight course the speed would have been 40 mil's an hour. The machine with the operator, weighed 9251b. But there is no public verification of tho flight. It was made in secret.; and there is only the inventors word—though American cornmen ta tuts give their word credit—for the conditions and result. The best public re-» cord for aeroplane flight was made by a Frenchman. Henri Farman, in November of last year, and the distance was six- [ tenths of a mile. Apparently French experiments have since improved on this result. The weight of Farman's machine is 11001b., and it is propelled at a speed of 25 to 30 milts an hour by a 50 h.p. motor. The supporting surface is 560 square feet: thus nearly 21b is supported by <.vcry square foot of area, fcantosDumont, who made such a success with dirigible baloons, is now busy with the aeroplane, and has made flights only a littler shorter than Farman's. Both in Germany and in England other workers are busily engaged in the aeroplane field; and every month, almost, there is a report of further progress gained. The dirigible- balloon, which relks upon gas for its lifting power, apparently has been carried close to practical perfection. The French "La Patrie," before it was lost in a gale which blew if from its moorings on 30th November last, travelled 142 miles, from Paris to Verdun in 7hrs smin —at a mean speed of over 20 miles /an hour: and this against a wind that blew at one time 24 miles an hour. The Zeppelin airship has done still better: one recent flight being over 200 mike iu Bhre. Two other German dirigible balloons, the "Parseval and the "Gross-," have reached a speed of 28 miles an hour. The French Government is reported to be so: well satisfied with "La Patrie" that five more are being constructed on the same model. Great Britain, with the "Nulli Secundum," obtained promising results before the machine was wrecked. Italy and Spain are also experimenting with dirigible balloons; and it is clear that, in the event of European war, at least an effort will be made to turn the successful experiments to military account. Whether dirigible balloons will in military use achieve all the ends hoped for by* inventors is very uncertain. Their efficacious flight is hampered so much by the conditions of tho air and by local" topography that wo imist wait to see them in action before any decisive profit can be predicted for the belligerent, employing mem. According to a recent American critic of progress, air-ships, formerly divided into "Dghter-than-air" and "heavier man air," are now -to be classified as '"ligbter-than-air " and " gasless " ; because a machine may be built heavier than air and still use gas as the principal aid to perfect buoyancy, with planes to lift the difference between the total weight of the apparatus and tlits weight lifted by me gas. It is with the gasless, type that the hope and labour of air-flight are bound up. The aeroplane, one form of gusless, is in the Wright brothers' model a glider with two planes. It obtains its lifting capacity by being forced against the ailby vertical propellers at a speed so great that the pressure on the under side, properly inclined, causes it to rise and maintain a course through the air, either parallel with the earth or at varying angles. What is called the .helicopter, another prominent model of gasless air-ship, uses plane surface for buoyancy and dirigibility, but does not apply the gliding principle. It depends for efficiency upon the power of horizontal screws or propellers, driven at a speed great enough to pull the machine vertically or obliquely into tho air. The helicopter has so far reached only the stage of models, which appear to give it soiu'j advantages over tho aeroplane. An aeroplane must start- with a speed of ?5 miles an hour to maintain a certain flight; while the model helicopter requires only half this speed for its sustained elevation in air. If the aeroplane's motor stops, however, the operator may hopo to conie safely to earth with a long glide; while tha helocopter, with a stopped motor, falls a once. A consideration of the most recent reports of experiment with all the g«sles3 types does not encourage anticipations that "the- conquest of the air" will }ki realised during a long period to come.— (Exchange.)