Although most test pilots would say that flying a wide variety of aircraft is the best preparation for test flying, very few could claim to have flown every type in the RCAF wartime inventory, with the British Commonwealth Air Training Plan and then overseas, or that their logbooks had recorded recent post-overhaul test flights in PBY Canso and Catalina flying-boats, DC-3 transports “and even Lancasters”—four-engine wartime bombers converted by DHC for peacetime mapping survey and maritime patrol missions.
For the finishing touch to his preparations, Bannock had recently flown with George Phillips, chief pilot of the Ontario Department of Lands and Forests, in one of the government’s Stinson Reliants, which had the Beaver’s high-wing layout, a less powerful engine than the Beaver’s Wasp Junior, and was also mounted on floats, Bannock was killing two birds with one stone by getting to know Phillips. Lands and Forests, on behalf of the Ontario Provincial Air Service, was dangling an order for twenty-five airplanes to replace the prewar Stinsons, one of which had shed its wing in flight, before the eager design teams at Fairchild in Montreal and DHC in Downsview. Lands and Forests was a major influence on the Beaver’s preliminary design, encouraging DHC’S engineering director, Doug Hunter, a wartime expatriate from the English parent company, to give it a design load factor of 5.25—that is, the Beaver is theoretically capable of carrying five times its gross weight.
The first flight of a new airplane in 1947 was a much less complicated affair than it is today. No special instrumentation was carried in the Beaver, and no computer-generated schedule governed Bannock’s actions in the air. He was pretty much on his own. He recalls his first-flight agenda for the Beaver. It was simplicity itself.
Plans for the first flight included the following:
Ground handling checks, including taxi tests.
High-speed taxi tests on the main runway to check directional control and rudder forces.
High-speed taxi tests to liftoff with and without flaps to check all control forces. Takeoff and climb to approximately 3,000 feet and carry out general handling and engine performance [tests] and obtain a general impression of speeds at different power-settings.
One strong memory Bannock retains after fifty years is the group of people whose labours had produced the creation he would now subject to a thorough investigation. They were bunched together on the concrete apron outside the experimental shop at the north end of Runway 33.
“I recall seeing Philip Garratt, managing director; Doug Hunter, engineering director; Jaki Jakimiuk, chief designer; Fred Buller, chief design engineer; Dick Hiscocks, chief aerodynamicist, and Jim Houston, power plant engineer.”
All six were wearing white shirts, in the formal style of their wartime generation of professionals, four of them with ties. The Beaver’s design team, the next day’s Globe and Mail photo caption stated, “consists of three young Canadians and an expert from Poland and England.”
Young Canadians Hiscocks and Buller, the two with the most intimate understanding of the airplane’s outline and inner workings, had their sleeves rolled up, looking businesslike and technical in their spectacles. Buller, of course, had just become aware that CF-FHB-X was named after him. Houston, the engine man, was tieless and in a short-sleeved shirt that acknowledged the impossibility of the man responsible for the overall powerplant installation wearing a white shirt with long sleeves. Hunter, the quite British production overseer from Hatfield, had turned his cuffs up only one turn.
The Beaver prototype during flight tests later in 1947, after it had earned the nose-to-tail speed line that characterized most civil production Beavers, DHC
Among the five men most responsible for the Beaver that morning, only their supervisor, the aristocratic Pole known to his colleagues as Jaki Jakimiuk, continued to wear his suit under the hot mid-morning August sun. It was heavily wrinkled at the elbows and knees. None of them wore sunglasses. Sunglasses were for pilots.
Garratt, also in shirtsleeves, was photographed later that day with a distinguished group that included Punch Dickins and Frank MacDougall, Ontario’s Deputy Minister of Lands and Forests. MacDougall would soon effectively decide, with his initial twenty-five-aircraft order, whether the Beaver or the Husky would be the bush plane to go into production.
“With full fuel (79 Imperial gallons) and a single pilot,” Bannock recalls, “we were well within the calculated centre-of-gravity range, so there was no ballast on-board.
“It was a lovely summer day, with a slight northwest wind, so I taxied out onto Runway 33 at approximately 10 A.M. and commenced the high-speed taxi tests, a series of skip-hops, checking brakes, checking rudder control—directional control.
“At the south end of Runway 33 (which gave me 6,000 feet of paved runway), I went through the takeoff checks that we had established. Runway 33 faces northwest, into the prevailing wind. I was hoping there would be no crosswinds.
“I commenced a series of high-speed taxi tests doing a short liftoff for the last two or three. I remember thinking I didn’t have enough brake-pedal travel for directional control on the ground. Later we installed pads on the brake pedals, which gave me greater leverage on the brakes. The next time I would taxi back and open up and just get airborne at the end of the run. I probably did that four or five times, checking longitudinal control, lateral control, just general handling, before deciding to take off.
“Using about 10 degrees of flap I opened up the engine to takeoff power (36 MP at 2,300 rpm) and was surprised how quickly the aircraft became airborne [in 15 seconds, according to the Globe and Mail’s story7]. A climbing speed of 74 mph was established with power reduced to 30 MP [manifold pressure, a measure of power derived from the amount of air being pumped into the engine] at 2,000 rpm. I levelled out at about 3,000 feet, staying within gliding distance of the field in case I had any powerplant problems. Cruise power was set at 28 MP at 1,800 rpm.
“After doing some gentle turns, climbs and descents, my first reaction was how pleasant the Beaver was to fly. It had good pilot visibility, good aileron response, and I had the feeling of lots of power up front.”
It was at just this moment, with Bannock warmed by the midsummer sun shining through a windshield that, on the prototype alone, was faired back overhead and into the wing’s leading edge, and the satisfaction of knowing the Beaver could fly and fly well, that the crisis struck.
Experimental shop and engineering staff peer at the pool of engine oil dripping from FHB’s powerplant after the abbreviated first flight. Access panels to the engine’s equipment bay are open. DHC
For most of the flight so far, barely more than ten minutes, Bannock had been preoccupied with the flight controls. He now paused to look out over the farmland that is now North York and Richmond Hill. Thornhill was a separate village. surrounded by fields, Dufferin Street was still a rural two-lane road which, during the war, had been interrupted by a liftgate at the end of Runway 27 whenever a newly built Mosquito fighter-bomber was being flight-tested.
Bannock, reassured by the big Wasp Junior’s steady throb on the climbout and the upward spiral he had maintained to stay over the airfield in case of trouble, had glanced at the engine instruments only a couple of times, and then very quickly. Now he looked again.
The oil-pressure gauge on the prototype was located on a three-in-one dial near the middle of the instrument panel. The all-important cylinder-head temperature gauge took up the top half, with the oil-and fuel-pressure gauges side-by-side below.
When Bannock glanced at it, the oil pressure was reading 35 pounds per square inch. The ideal