Canada’s Rotary Wing Heritage

On February 23, 1909, the pioneering efforts of Dr. Alexander Graham Bell's AEA (Aerial Experiment Association) culminated in the Silver Dart taking to the skies, launching Canada's air age. What is not as well known is that the first powered flight by a "fixed wing" aircraft was matched by the rudimentary experiments in rotary wing and vertical take off and landing (VTOL) craft that took place in Winnipeg in the same year. While being in the forefront of aeronautical development for a century, vertical flight development in Canada has been inauspicious and fraught with only a handful of tentative projects destined never to achieve production status.

At the dawn of aviation, Manitoba was the scene of experiments and demonstrations with "birdmen" and "birdwomen" investigating flight in the form of balloon ascents and parachute flights. The next development occurred in 1909 when 25 enthusiasts gathered at the Winnipeg Industrial Bureau to form the Aero Club of Canada on March 31, 1909 "in order to assist and promote practical aeronautics by encouraging Canadian Inventors." Their initial ambitious project resulted in the first aircraft designed and built entirely in Canada, the "Aero Car Canada", which was unveiled to the public shortly after the association's inauguration; their second program led to the design of Canada's first helicopter.

In describing the efforts of this pioneering association, newspaper accounts noted that it was the first "of its kind in Canada". The eventual Chair of the club was to be Hon. Sir Hugh John MacDonald, the former Premier of the province and the son of Sir John A. MacDonald. One of the first functions of the Aero Club of Canada was to establish headquarters in Winnipeg and create a constitution that would enable aeronautical research and support of individual projects by providing communication with other scientific associations worldwide.

Soon after its creation, founding member, William J. Robertson commenced on the first of the Aero Club of Canada's efforts, the "Aero Car Canada" (also variously described as the "Aerocar Canada"), the first aircraft designed and built in Canada. Despite its innovative design, the Aero Car Canada displayed on July 14-15, 1909 at the Happyland Ball Grounds in Winnipeg, was not successful. Its first flight was delayed partly by weather as well as a lack of parts that were being sent from the United States. It was not until the arrival of Eugene Burton Ely, demonstration pilot for Curtiss Aircraft who flew in Winnipeg on July 15, 1910, that the first powered flight in Manitoba was recorded.

A second aircraft design was initiated in 1909 under the auspices of the Aero Club of Canada, although it was not able to proceed beyond research and design. The Kelsey Helicopter, named after its Winnipeg inventor, Edwin E. Kelsey, was revealed to the public on April 6, 1909. Described as a "dirigible helicopter", although the design proved to be successful in scale model form, lifting into the air and flying even in a confined space, it never progressed to final construction. A further five aeronautical projects commenced by members of the Aero Club of Canada were similarly fated to never be completed.

In other rotary wing developments at the turn of the century, engineers and designers in France struggled with the basic configuration of contra-rotating rotors. In 1907, Paul Cornu and Louis Brequet had both built rudimentary craft that could lift into the air, but could hardly be considered successful designs as both suffered from control problems and were abandoned. The following year, a young Igor Sikorsky in Russia also experimented with a similar design but the resulting unmanned machines that were tested in 1909-1910 were only able to rise a few feet into the air. It was not till decades later, that Brequet with the Gyroplane (1935), Professor Henrich Focke with the Focke-Achgelis Fa-61 (1936) and later Sikorsky with the VS-300 (1939) returned to tackle the inherent conundrums of rotary wing flight, to create the first truly successful helicopters.

In Canada, during the same period, a number of designers struggled with rotary wings. In the 1930s, the Hess Helioplane and Duben Helicopter were unsuccessful designs that were constructed and tested but proved unable to sustain hover or flight. However, in Homewood, Manitoba, an almost unheralded project, designed and built by brothers Douglas, Nicholas and Theodore Froebe was undergoing testing. In 1936, using a "backyard mechanics" approach, the brothers had cobbled together a simple, but functional contra-rotating helicopter. The open tube frame and rotors were built from aircraft chrome molybdenum steel while other components were either handcrafted or derived from available automotive or farm machinery. The sturdy machine utilized two concentric, contra-rotating rotor blades powered through a right-angled drive by a used 4-cylinder air-cooled, front-mounted de Havilland Gipsy engine.

Doug Froebe was the primary test pilot during a series of test flights undertaken in 1937-39, recording Canada's first controlled, manned vertical flights. His notebooks, logbook and letters (now preserved at the Western Canada Aviation Museum) provide a vivid picture of the pioneering flights. "During the first attempt to fly, the tail came off the ground about three feet. I hauled the stick clear back and the front wheels came off one at a time... when I'd shut the throttle down, it would just take its time coming down – didn't stall – just float down like a feather." Although the helicopter suffered from severe torsional vibration, it easily transitioned into vertical and hovering flight, and while only flights of short duration were attempted, a total of four hours and five minutes was logged before the test flights were ended on March 2, 1939.

Throughout the 1940s, the Froebe brothers continued to modify their experimental design and made efforts to sell their concept to Canadian and American interests including the U.S. Navy during the Second World War. Gradually, they realized that more viable production helicopters rolling out of Bell, Hiller, Piasecki and Sikorsky companies, doomed any hope of commercial or military contracts. Despite their record of successful test flights, the Froebe brothers did not apply for a patent, with their helicopter being largely forgotten, although the original machine resides today at the Western Canada Aviation Museum.

In the immediate postwar years, Canada's only certified helicopter was developed, the Grey Gull designed by Bernard Sznycer (assisted by mathematician Selma Gottlieb). Designed for Intercity Airlines with the same basic configuration of the successful landmark Sikorsky designs, the SG-IV-C single rotor prototype helicopter was designed and built in Montréal as a purpose-built machine able to withstand Canada's harsh northern environment. The test pilot, aptly named Henry J. Eagle Jr., carried out its maiden flight on July 9, 1947, noting a completely vibration free flight. After successful completion of the test program, the first production machine, SG-IV-D Grey Gull, was flown on February 6, 1948, and granted a Certificate of Airworthiness on March 15, 1951.

During tests, the Grey Gull managed to fly in the most adverse conditions, with comments such as "Temperature – 10 degrees below zero. Altitude- instrument covered with snow. Wind – Terrible. Aircraft – normal in all respects." Despite the error-free test program and glowing reports revolving around its robust construction, stability and flight control, after no contracts were obtained, financial backing was withdrawn in 1954, leading to the program's demise. The Grey Gull is now restored to display condition at the Reynolds-Alberta Museum in Wetaskawin, Alberta.

Although no other helicopters have been designed and constructed in Canada since the 1950s, three notable rotary and VTOL concepts have emerged as historical footnotes. The first two designs owed their existence to the Avro CF-105 Arrow project that dominated the late 1950s headlines. In the aftermath of the cancellation of the Avro Arrow on "Black Friday, February 20, 1959, engineer Peter Payne, together with a small group of fellow designers and engineers, created Avian Aircraft Ltd. with headquarters at Georgetown, Ontario. Their "start-up" concentrated on the design and construction of helicopters and autogyros, resulting in the design of the Avian 2/180 Gyroplane.

The diminutive two-seat experimental Gyroplane was a compound aircraft powered by a "buried" 200hp Lycoming LO-360 air-cooled engine. It could take off as a helicopter and once in flight, power being transferred to a tail-mounted, four-blade, dueled pusher propeller, while the rotor free-rotated. The Avian 2/180 first flew in spring 1960 with a small production run following. During a protracted development period, the Avian 2/180 underwent various modifications and improvements before being granted approval as a civil aircraft in 1967 in both Canada and the USA. In spite of its spirited performance, high production costs prevented further development.

The second VTOL project coming as a result of the Avro Aircraft company was the improbable story of the Avro VZ-9 AV Avrocar, a "black" project that had been underway in relative secrecy while the Avro Arrow had received star treatment. Initially funded by United States Air Force, the two-seat Avrocar was designed in 1958 as a "proof-of-concept" test vehicle for a future line of supersonic disc-shaped "flying saucers". During its conception, the United States Army showed interest in the project as a contender in a "flying jeep" competition. The Avrocar intended to exploit the Coandă effect to provide lift and thrust from a single ducted "turborotor". Three Continental J69-T-9 jet engines at 660 lbf (2.9 kN), mounted inside the fuselage "blew" onto the rotor, which in turn, diverted the exhaust out the rim of the disk-shaped aircraft to provide anticipated VTOL-like performance.

The futuristic Avrocar had its first untethered flight on November 12, 1959 with the second of two production machines completing a flight test program during 1959-1961, never able to rise out of "ground cushion". The performance fell far short of design objectives, and stability remained elusive resulting in both the U.S. Army and Air Force funding being cancelled in March 1961. Both examples still exist with the wind-tunnel model in storage at the Garber Reclamation Facility of the Smithsonian's National Air And Space Museum and the flight test model under restoration in the U.S. Army Transportation Museum at Ft. Eustis, Virginia.

The only other VTOL project coming out of Canada is the "convertaplane" Canadair CL-84 Dynavert, Canadair designed and manufactured a series of V/STOL (vertical and short take off and landing) turbine tilt-wing monoplanes between 1964 and 1972. Only four of these experimental aircraft were built with three entering flight-testing. Two 1,500 shp (1,100 kW) Lycoming T53 shaft-turbines were used to drive the two 14 ft (4.3 m) four-bladed propellers. The wing was tilted vertically to provide lift and hovering capability much like a helicopter and then could be lowered into a horizontal position to convert the Cl-84 into a "conventional" aircraft. The U.S. military became the prime focus of the subsequent development, with the CL-84 intended to serve as a high-speed shipboard transport.

The CL-84 prototype, CF-VTO-X, first flew in hover on May 7, 1965 and although the airframe and a subsequent production example: CX8401 were lost in accidents, the sole remaining test aircraft underwent a grueling evaluation in 1973 onboard the USS Guadalcanal aircraft carrier. In the face of gale storm conditions, the 84 performed magnificently in tasks such as ferrying troops and "blind-flight." In spite of rave reviews from over 40 pilots, with the wind-up of the Vietnam War, the CL-84 did not land any production contracts.

The two surviving CL-84s ended up in museums: CX8402 resides in the Canada Aviation Museum in Ottawa alongside another faded dream of technological greatness in Canada – the Avro Arrow.

CX8403 was never flown; it was donated to the Western Canada Aviation Museum. Today, only the fuselage sits forlornly in the main display gallery.

Museum visitors who have seen either examples of the Canadair CL-84 Dynavert, sometimes take time to read the displays that tell the story of one of Canada's greatest achievements in V/STOL development and may pause to ponder "what if?" With the end of the last indigenous vertical flight program, the Canadian aviation industry has now been relegated to purchasing "off-the-shelf" helicopters from abroad.