O.Thetford British Naval Aircraft since 1912 (Putnam)

CURTISS TWIN CANADA

   One hundred of these bombers were ordered for the RNAS in 1915 (Nos.9500 to 9599), but the contract was subsequently cancelled. One example (No.3700) was eventually delivered to Hendon in November 1916. Designed by Curtiss and built in Canada, the Twin Canada had two 160 hp Curtiss XV engines.

K.Molson, H.Taylor Canadian Aircraft since 1909 (Putnam)

Curtiss Canada

   In 1914 the Curtiss Aeroplane Co had made a twin-engined flying-boat, the Curtiss H-1 America, for a projected transatlantic flight and its pilot was to have been Lt John Cyril Porte. The outbreak of war stopped the projected Atlantic flight but Porte interested the British Admiralty in the machine and orders were placed for the prototype and a production version, the H-4, which became known in the RNAS as the Small America to differentiate it from the H-12, the Large America.
   The Admiralty was impressed with the type and requested the Curtiss Co to design a landplane counterpart. Glenn H. Curtiss laid out a design and took out US Patent No. 1,228,382 to cover it. The patent also went on to cover a flying-boat layout developed from the landplane, so what had started as a flying-boat developed through a landplane and back to a flying-boat. The proposed flying-boat had booms protruding aft from the engine nacelles to support the tail, the first known projected Curtiss design to do so and thus it was the ancestor of the Curtiss H-7 and the later Navy-Curtiss NC flying-boats of transatlantic fame.
   The Curtiss Co in Hammondsport, New York, was too busy with war orders to complete the design, so responsibility was given to its new subsidiary, the Curtiss Aeroplanes & Motors Co at Toronto. Frithiof Gusaf Ericson was appointed Chief Engineer. Anthony H. Jannus was engaged as pilot and consultant, and Dr Albert F. Zahm also acted as consultant on the project.
   The new machine had been known as the Columbia but was named the Canada after the project had been transferred to the Canadian company. It had a conventional wire-braced wooden structure, fabric covered. The undercarriage was unusual and was the subject of US Patent No. 1,246,020 assigned to Glenn H. Curtiss. Each side consisted of a pair of struts forming a V and mounted vertically below the engine nacelles. The struts were braced laterally by wires, and an inverted leaf-spring was mounted at the apex of the struts. An axle was held at each end of the leaf-spring and the inboard end of the axle was pin-jointed to a cabane structure below the fuselage. A wheel was mounted outboard of the spring on each axle. A Sperry autopilot or stabilizer was fitted, which may well have been the first time such a device had been installed as original equipment. The Canada was designed to have two 160 hp Curtiss VX engines, handed to eliminate torque, and drive three-bladed propellers, but these engines, were not available in time so test flying of the prototype in Canada was done with a pair of 90 hp Curtiss OX engines.
   Work on the Canada was started in May 1915 and a trial assembly of the uncovered components began about the end of June. The assembly took place in the open at Strachan Avenue. On 11 August, 1915, the Toronto World reported that the first flight would be in ‘about two weeks’ but from then on wartime censorship imposed silence on the Canadian press.
   The Canada was moved to Long Branch on the western outskirts of Toronto and first flown there on 3 September by Anthony Jannus. On a second flight that day a passenger, probably Ericson, was carried. On 7 September the aircraft was officially demonstrated to Sqn Cmdr J. C. Porte who had for security reasons travelled to North America under the assumed name of J. B. Scott. The Canada was accepted and shipped to Britain. It had been built and flown with a balanced rudder, identical to that used on the H-4 flying-boats, but this was replaced by an unbalanced rudder before shipping. It arrived damaged at Farnborough, according to a report of 21 October, and repairs were put in hand. The Canada had, apparently, been sent without engines, for the installation of 150 hp Sunbeam engines was considered but not proceeded with and Curtiss VX engines were installed as originally planned.
   Sgt Maj W. B. Power was the pilot for most, if not all, of the Canada’s flights at Farnborough, which probably began in the last part of November. A failure of the upper-wing overhang resulted in bracing struts being installed to replace one set of wires. Also, it was thought that the propeller design could be improved upon so orders were placed in Britain with both Vickers Ltd and the Lang Propeller Co for new propellers. During the Farnborough test programme the wing bracing cables were replaced with double streamlined RAF wires which improved the top speed.
   By 16 January, 1916, it was said by those concerned that after partial trials they were very pleased, and it was doubtless as a result of them that orders were placed at the beginning of the year with Curtiss in Toronto for eleven more aircraft, ten for the RFC and one for the RNAS.
   However, there were problems. The machine was considered unsatisfactory for use as a bomber but suitable as a platform for a 1- or 2-pounder gun if rear protection was added, but how this protection was to be provided was not stated. Vickers was asked to design a 1-pounder gun mounting and the resulting design gave 86 deg of elevation and 60 deg of depression for the gun but the mounting was not made.
   The general design of the Canada was stated to be ‘fairly satisfactory but the design and workmanship of the details is exceedingly bad and, in some cases, every principle of (good) design (practice) appears to have been violated’. The fuel system was thought to be particularly vulnerable to battle damage and required modification.
   On 29 January, 1916, a Lang propeller on the port engine burst in flight due to faulty glueing. Sgt Maj Power kept the starboard engine going and managed to land on rough ground with no injuries to himself or the three passengers, and he was commended for his action. The Canada suffered extensive, but repairable, damage to all wings, the nacelles and undercarriage, as well as the propellers.
   The machine was repaired and Power made a climb test on 27 April. By 4 May it was noted that performance was disappointing and the aircraft had given a lot of trouble. No test of the Sperry stabilizer had been carried out by 5 May and it is doubtful that it was ever tried; this seems surprising as it was probably the first such device seen at Farnborough. There is no record of any tests after early May.
   In the meantime, work had been proceeding rapidly on the batch of eleven improved Canadas at Toronto. These incorporated strut bracing to the wing overhang, constant-chord ailerons (This reduced the upper wing span to about 75 ft 4 in (22-96 m) and the wing area to about 787sqft (73-1 sqm)) and wing skids under the lower wings. The Sperry stabilizer was not fitted, but, apparently, the fuel system remained unchanged. These machines were designated as Canada Model Cs. They were shipped to Britain untested in the early spring of 1916, and a further order for 25 machines, with unknown improvements, designated Canada C-2s, was received. This order was cancelled about the end of June or early July but it seems that the first Canada C-2 must have been nearly completed then for a Canada has been reported in the factory in December when Canadian Aeroplanes Ltd took it over.
   The RFC Canada Model Cs were at the Southern Aircraft Depot, South Farnborough, in May, and a Mr Sudlow was on his way from Toronto to supervise their erection, and by 7 July they were reported as waiting for propellers. On 26 August an order was issued to stop erecting the machines as no suitable engines were available.
   The RNAS Canada Model C, serial 37001, was being erected at Hendon on 6 June and reported ready for test on the 20th. Shortly alterations were started, apparently mainly to the wings. New crankshafts were found to be required and these were still being awaited when the machine was scrapped in January 1917. Like the RFC Canada Model Cs, there is no known record of a flight test being made.
   The unsatisfactory performance of the Canada can be attributed to three things. First, its design had been laid down before air warfare had developed and was initially accepted before any had been experienced by the British air forces. Secondly, its unsatisfactory engines would have condemned it regardless of other factors. Thirdly, poor detail design and workmanship simply compounded the other problems.
   Unsatisfactory as the Canada was, it nevertheless occupies a secure place in Canadian aviation history as the first twin-engined aircraft ever built or flown in Canada.

Two 90 hp Curtiss OX* or 160 hp Curtiss VX. Span, upper 75 ft 10 in (23-1 m), lower 48 ft (14-63 m); length 33ft 4f in (10-18m); height 15 ft 6in (4-72m) approx; wing area 827sqft (76-83sqm). Empty weight 4,700lb (2,134kg); loaded weight 7,000lb (3,178kg). Maximum speed 90mph (144-8km/h);** initial rate of climb 390ft/min (102-4m/min);*** service ceiling 5,750ft (1,752m).***

*Maximum speed with Curtiss OX engines is reported as 70mph (112-6km/h).
**Reported as 102mph (164-1 km/h) after being fitted with RAF wires in England.
***Estimated by author from climb test figures of 27 April, 1916.