FlightGlobal.com
Home
Premium
Archive
Video
Images
Forum
Atlas
Blogs
Jobs
Shop
RSS
Email Newsletters
You are in:
Home
Aviation History
1924
1924 - 0265.PDF
MAY 8, 1924 The undercarriage is of the type found on torpedo 'planes, i.e., there is no axle connecting the two wheels, each of which is supported on a pyramid of three tubes, two of which run, in Vee formation, to the fuselage longerons, the third being taken to a point inside the centre-section of the wing. Shock- absorbers are housed inside the wing, no springing being pro vided at the bottom of the chassis struts. The wheels are of a type similar to those used by Mr. Shackleton on the A.N.E.C. monoplanes at Lympne last year, consisting of laminated ash rims with three-ply discs. On tests one of the Daimler wheels withstood without breaking a load of 600 kg. (1,320 lbs.), although its weight was but 1 -2 kg. (2 -64 lbs.). This form of undercarriage was chosen by Herr Klemm partly because he believes that a wheel axle raised but a few inches above the ground is likely to throw a machine on to its nose in long grass, and partly because the travel of the wheels can be made more than the radius of the wheel, as in the ordinary Vee-type chassis. Also the shock-absorbers can be totally enclosed in the wing. The objections to it are, of course, fairly obvious. A hard landing may strain the wing structure, which may consequently fail on a subsequent flight. When the centre-section of the wing is removed, the undercarriage has to be braced to stabilise it. This is done by three cables, one running from one wheel to the other, and one on each side running to a point on the fuselage. This bracing is sufficient for light loads only, of course, such as for trailing the machine behind a motor-car. The engine fitted in the L.15 is a motor-cycle engine of 7-9 rated horse-power. It is stated that at the speed at which it is run in the machine the actual power developed does not exceed 12 b.h.p. The engine is an air-cooled Vee- twin, mounted on a steel structure in the nose of the fuselage. and cowled in all but the top of the cylinders. A planet reduction gear has been added to obtain better propeller efficiency. The petrol tank is carried behind the engine, and •direct gravity feed is used. Mention has been made of the fact that the L.15 is convert ible from light 'plane into glider a.n&* vice versa. This is accom plished by building up the nose of the fuselage as a separate unit. The " glider nose " contains a cockpit and the usual controls, so that by adding a short length to the control cables the machine can be controlled from this cockpit, while, if desired, a passenger can be carried in the cockpit between the wing spars. Incidentally, the controls then allow of the machine being used for school work (dual). For use as a light 'plane the '' glider nose '' is removed and the nose contain ing the engine and tank substituted. The fastenings used for securing the noses are of a type requiring no adjustment and no special tools. When the machine is used as a light 'plane two-seater the passenger sits immediately behind the pilot, in a cut-out in the trailing edge and just behind the rear spar. It would appear likely that with this arrangement the centre of gravity might be rather far aft, as the combined weight of pilot and passenger would, it would seem, be likely to more than make up for the weight of the engine farther forward. * But few particulars are available relating to the charac teristics of the L.15. The wing span is stated to be 12 -6 metres (41 ft. 4 ins.). The engine, as already stated, develops about 12 b.h.p. at the speed at which it is run. Already several very good performances have been put up by Herr Schrenk. Thus during a solo flight he reached an altitude of 2,150 m. (7,050 ft.). With passenger the machine has climbed to 1,100 m. (3,600 ft.). During a solo flight the machine remained up for 3 hours 5 mins., and while carrying a passenger a duration of 2 hours 2 mins. was attained. The longest non-stop cross-countrv flight made solo was 190 km. (118 miles), and one flight of 120 km. (75\ miles) was made with a pas senger. In view of the low engine power, these performances are highly creditable, more especially so when it is remem bered that the machine was virtually designed four years ago, i.e., before the Rhon competitions had really shown the way to the efficient glider and light 'plane. S3 H H H A WATER-TEST FOR LANDPLANES An Interesting Air Ministry Experiment As foreshadowed in a previous issue of FLIGHT, an interesting experiment was carried out on Friday last at Felixstowe air station by the Air Ministry. The object of this experiment was to obtain as much information as possible on the behaviour of an ordinary land machine when the latter has made a forced descent upon the sea. For the purpose of this test the Air Ministry obtained one of the old " D.H.18 " four-seater enclosed cabin 'buses, which it was proposed to " land " in the sea, and, having " rescued " the pilot, make careful observation of the machine's behaviour. The cabin was made as watertight as possible, all openings, seams, etc., being carefully caulked. No special flotation gear was fitted. On the day of the test, conditions were quite favourable, the sea being not too rough and there being a helpful head wind blowing. A number of officials and others gathered to witness the experiment, among whom may be mentioned Major-General Sir Sefton Brancker (Director of Civil Aviation), Wing-Commander Cave-Browne-Cave (Directorate of Supply and Research), while Mr. Walker, of the De Havilland Aircraft Company, looked sadly on as the hardy " D.H.18, G-EAWW " slowly but surely turned into a submarine. Shortly after 11 a.m., Flight-Lieut. A. C. Rea brought the " 18 " down low over the water, and making for an R.A.F. motor launch standing by to render first aid, effected a normal " level keel " landing. As the wheels of the machine touched the water they naturally exerted a drag on the machine, with the result that the tail came up, and the aeroplane nosed into the water. At first it stood almost vertical, with the main planes submerged, then it slowly rose out of the water just a little, and finally settled down with the fuselage at an angle of about 45°, the lower plane almost completely submerged and the top plane just awash. Had there been anv passengers in the cabin they would probably have been provided with a rival to the new Zoo aquarium ! Meanwhile the pilot, although well out of the water, managed to retain his position—or some of it—in the cockpit during the early stages of the " landing," and when the machine began to settle he slid down the fuselage to the centre section and assisted in the loading of extra ballast into the cockpit, before leaving his craft to its watery fate. The fuselage now assumed an angle of about 30°—the "Lion," of course, being thoroughly submerged—and the machine floated thus, drifting with the tide, for about 20 minutes. When a rope was made fast to the machine it began to sink lower into the water, until, after about 25 minutes from the time it first struck the water, the pilot's cockpit was awash. Five minutes' later " G-EAWW " settled down for good—only the tail remaining above water. No attempt is to be made to salve the aeroplane, but the Napier " Lion " will, of course, be rescued. H E IS m Imperial Airways AT long last a settlement has been come to in the regret table dispute between the newly-formed Imperial Airways, Ltd., and the pilots and ground staff of the old, absorbed air line companies. For over a month the British air services were idle, and the French machines in the meanwhile reaped the benefit of the spring air-traffic work. On May 2 the follow ing statement was issued :—" The Imperial Airways, Ltd., announce that an agreement has now been reached to the satisfaction of all concerned, between the pilots, mechanics, and ground staff of the absorbed air transport companies and the Imperial Airways, Ltd., and service will be resumed on Monday next (May 5)." The terms of the settlement have not been officially announced but it is understood that one of the principal points of the agreement is the creation of a new post—Air Superintendent—to which Major H. G. Brackley has been appointed. Major Brackley has but recently returned from the British Air Mission to the Japanese Government. Royal Tournament THE BOX Office seats can now be booked at 66, Victoria Street, S.W. 1, for the opening ceremony, May 22, at Olympia, or any subsequent day, afternoon or evening, up to June 7, on which day the Tournament finishes. It is well to secure seats in advance, as last year many were disappointed at the " House Full " notices which confronted them upon arrival at the show. 265
Sign up to
Flight Digital Magazine
Flight Print Magazine
Airline Business Magazine
E-newsletters
RSS
Events
