Flight, January 1925

THE VICKERS "VEDETTE" FLYING BOAT
First Machine Designed and Built by Canadian Vickers

   As the first aircraft to be designed and built in Canada, from home-grown timbers mostly, considerable interest attaches to the Vickers flying boat, designed and built by Canadian Vickers, Ltd., of Montreal. The machine was required especially for forest fire patrol and for photographic survey work, and the innumerable lakes and rivers of Canada naturally suggested the seaplane or flying boat as a suitable type. After going into the pros and cons, of the matter, it was decided to produce a flying boat, and the Vickers "Vedette," the subject of the accompanying photographs and description, was the result. Mr. W. T. Reid, at one time chief designer to the Bristol Aeroplane Co., was taken on as designer, and arrived in Canada about the middle of June. After getting together a staff in Canada, Mr. Reid set to work, assisted by Mr. Newall, late of Handley Page's, and with characteristic hustle the machine was finished and flying by November 3. Actually the machine could have been finished about a fortnight earlier, but the work was slowed down as the arrival of Flying Officer Plenderleith, who was to test the machine, was delayed.
   The Vickers "Vedette" was designed for either the Rolls-Royce "Falcon" or the Wolseley "Viper," the former engine being fitted at first so as to make absolutely sure of getting the required performance, but being replaced later by the "Viper" when it was found that the latter gave well over the specified performance. Incidentally, it might be mentioned that the forest patrol and photographic survey work had previously been carried out mainly with Vickers "Vikings" or with H.S.2-L's, but that these machines were naturally rather too large when it was only desired to carry pilot and photographer. The "Vedette," in spite of her relatively low power, carries pilot and two passengers, or their equivalent weight, the total disposable load being 480 lbs. Considering that the power is but 200 h.p., the "paying load" is quite good.
   The general lay-out of the Vickers "Vedette" is well shown in the accompanying general arrangement drawings and photographs. The machine is of orthodox design in every respect as regards the general disposition of its component parts, being a pusher biplane with flying boat hull. The latter is, in shape, not unlike the famous Vickers "Vikings," i.e. there is a vee bottom with two steps, but the sides are curved gradually into the cambered deck fairing. Constructionally, however, the "Vedette" differs in being planked with but a single skin, afterwards covered externally with fabric and doped.
   The wing structure is of normal design, but a somewhat unusual feature, at any rate in flying boats, is that there is but a single pair of struts on each side, in spite of the fact that the span is 42 ft. The pilot's cockpit, with accommodation for two, is placed immediately forward of the leading edge of the lower plane, with a third cockpit for observer in the nose of the boat, the fairly pronounced stagger making this arrangement possible.
   The Wolseley "Viper" engine is mounted on four engine struts rising from the boat hull, and is placed close under the top plane to give clearance to the pusher airscrew. Wing tip floats of usual type are mounted under the lower plane, at the points of attachment of the inter-plane struts.
   As already mentioned, the "Vedette" was tested by Flying Officer Plenderleith, and a very good performance was established. With the Rolls-Royce "Falcon" engine the machine was found to have a top speed at sea level of 107 m.p.h., while with the Wolseley "Viper" the top speed at sea level was 98 m.p.h. The following performance figures all relate to the machine as fitted with the "Viper": Speed at 5,000 ft., 95 m.p.h.; at 10,000 ft., 87 m.p.h. climb to 1,000 ft. in 1-6 mins.; to 5,000 ft. in 9-5 mins. and to 10,000 ft. in 27-5 mins. The ceiling is 13,800 ft., and the landing speed about 45 m.p.h. With full load the machine gets off in 15 secs., is very dry, and lands without any "vices."
   The main dimensions of the "Vedette" are: Length overall, 32 ft. 10 ins.; height, (11 ft. 9 ins.; wing span, 42 ft.; chord, 6 ft. 9 ins.; ,gap, 6 ft. 6 ins.; stagger. 19-25°; dihedral, 2°; angle of incidence, 6°. Area of main planes with ailerons, 490 sq. ft.; area of tail plane, 34 sq. ft.; area of elevator, 17 sq. ft.; area of fin, 7-5 sq. ft.; area of rudder, 13-5 sq. ft.
   The weight of the machine empty, but with water, is 2.263 lbs.; petrol (55 galls.), 396 lbs.; oil (9 1/2 galls.), 64 lbs.; disposable load, including pilot, 480 lbs.; total loaded weight, 3,203 lbs.; wing loading, 6-53 lbs./sq. ft.; power loading, 16 lbs./h.p.