AIRCRAFT TYPES.

Press, Volume LV, Issue 16507, 26 April 1919, Page 10

AIRCRAFT TYPES.

SHIPS AND PLANES

THEIR PIECES IN COMMERCE,

While the first successful heavy bombing aeroplane was actually being built, a well-known aeronautical engineer expressed his conviction fhat, •apart, from unforseeablo discoveries, the limit of size for an aeroplane was a machine having a margin of carrying capacity of about one ton, and that' aeroplanes of an all-on weight of two or three tons would be the exception (writes Major C. C. Turner in -the London "Daily Telegraph"). Without going into the technical arguments put forward in support of this opinion, which, at the time, and from.the point of view taken, no doubt had some justification, it may simply be recorded that machines of twice the size indicated are now in common use.

At this moment there is supposed to be a struggle going on between the airship and the aeroplane, and aeronautical experts are said to be ranging in opposite camps. That, however, depends upon what is meant by an "expert." TThere are, indeed, advocates of both divisions, but most of these advocates are either official or private persons with interests at stake. An expert capable of forming independent opinions j would scarcely take sides in what is at i present a rather empty controversy. ; He would first make sure of his facts, i and then he would point out that there ; are clear fields of activity. He would not compare the great airship of tho j near future—we are told it is to have a capacity of 10,000,000 cubic feet of gas—with the big aeroplane of to-day. Hβ would find out what is being done in the way of big-aeroplane design, and what we may expect will take the air •within a reasonable period. Hβ would be yery cautious about that 10,000,000 cubic feet airship, which at present is altogether speculative, and would prefer to deal with the types of about a I quarter that size, which" are the imm&-! diately forthcoming items in the Bri- \ tish. airship programme, and are rather! smaller than the newest Zeppelin. And ; he would soon perceive that tho big J aeroplanes of to-day are to be greatly ! surpassed in size by machines that will be ready by the end of this year or tho i beginning of nest. . These machines aro altogether outside the limits set by the authority referred to above. The statement made tho other day that "the latest Handley-Page machine, with its span of 127 ft, represents the maximum size-limit of the. commercial aeroplane" , is nonsensical. '-

BIGGER MACHINES COMING. There are maciiines of oOCO-h.p. actually on the stocks, not designed by cranks, but the projects of famous [ firms, which arc making ready to com- ! ply with tho demand for Transatlantic travel facilities, and intend those craft to carry comfortably from 60 to 100 passengers with that safety and regularity which alono would justify tho outlay of capital involved. And all this work is going on in spito of sonio uncertainty as to the conditions on which commercial aviation will be conducted. Apart from the hectic projects of some concerns, aviation is calmly confident of the future, altuough its developments at first may be retarded. > Tho supposed struggle between the airship and tho aeroplane for survival and labour unrest are making capital extremely shy, naturally and rightly so; and a circumstances not at all to br> regretted provided the time of waiting be wisely employed. But there is a debit side to the account, and that is the danger of handicapping the industry in this country, and of freezing out somo of the most promising enterprises of private inventors and small firms. Already one hears of tho departure from this country of talouE seeking outlet nbroad. In the Royal Air Force itself there is a danger of the dispersal of talent, _ both > in the aeroplane and the airship divisions, which will set the clock back seriously. Germany, we may be sure, will mako one of her first cares the consolidation' of the technical protrress achieved during the war. and will retain a hold on her best engineers and inventors.

SOME NEW IDEAS. There is in London an Australian aeroplane design that arrived top late for the war, but, in the opinion of many aeronautical engineers, deserves a trial. It is different in essential features from existing, types, and it has done a rather remarkable thing in model form, of a total weight of about 3cwt, making over twenty flights unmanned, driven by a 6 h.p, engine, and landing each time without injury. The design is for a large passenger-carrier, the passengers being housed clear of the engines; and it comprises an ingenious self-balancing which, successful in the model, promises success also in. the full-sized machine. All the , quantities and stresses have been calculated, and although there is always a margin of _ uncertainty in these now departures, it makes a fair claim on inquiry. At the least there are foatures in the "design which, on their own account, are worth a trial. But at a time when all save the largest ostnblishments are marking time, there is but little hope for a newcomer, and one takes leave to doubt whether the methods employed by. the authorities are calculated to encourage such now ideas, now that tho war is over. It is curious to watch the airship- • aeroplane controversy, and to note each side in turn trotting out some specious objection which could onlv impress the non-technical. Thus, against the big aeroplane it has been urged that its size and weight are so great that forced landings mean serions trouble, because of the rarity,of big flat fields, and because breakdowns involve costly and laborious removal processes: whereas the ordinnrv aflrnr»ltn° is not gravely '•"indjeed bv such incidents. This argument overlooks the fnct that with the bis: neronlane of to-dnv forced landings are rnpidly being rendered all but impossible. In regard to the numbers of the ground personnel necessary, the aenrolnne.of course has the best of the airship every.time.

OF THE AIR-BOAT. The airship exclusivist overlooks the big airboat which', on account of the comparative simplicity of its alighting gear, will be capable of superior performance, power for power, the smaller amount of head-resistance contributing to this. For this division there is no expense of aerodrome maintenance; and the sea being one huge aerodrome, without hedges, trees, and houses, the air-boat is under no necessity. to maintain high altitudes in flight. Further, the speed of the traffic with which it will nave to compete is very much, less than the speed of railways. For very long voyages a good case can be made out for the airship. But the cost of building, of shed room, and of maintenance makes it a bigger proposition for capital. That it has a great

future is beyond question. The Germans ran passenger airship services during many years before the war and it was their proud boaet that of the 17,221 persons carried none was injured. The services onlv showed a good financial side by reason of the fact that they were State-aided, the vessels all being potential war airships. Far better could be done nowadays. So far as Great Britain is concerned, however, we have never yet succeeded in the bijr rigid division, in spite of the fact that we have had lor the past five years the advantage of j Germany's experience, and the technical I data of Germany's disposal. Possibly jwe have tried to introduce too many J improvements. At any rate, it was not until last spring that a British ngid airship was produced that was of any service at all. The vessel that was launched last November, the R. 31. has not put up more than a dozen hours of flight, and has proved incapable of getting above the lower stratum of the air. It is a matter upon . which the public are entitled to bo in- ; formed at a time when so much ie j being claimed for the productions of i our airehins department. The R. 33, I«f which the preliminary trials have i just been postponed, is. it is an-, nounced. to cross the Atlantic. Sheis to heat all existing records. Quite probably these rich anticipations will bo realised; but past experiences with airships show that it is best not to discußS ptiblielv auestiong of "per- i formance" until the nctual achieve- ' znent. Officials should have learned ere this that unfulfilled 1 anticipations ■*«» followed hs jsnblic reaction.