Canadairs Basic Jet Trainer
A 400-mile-an-hour bid to capture a - lucrative military, civil mark
A firm decision to develop a modern side-by-side basic jet training aircraft, known as the CL-41 or Canadair Trainer, has been formally announced by Canadair Limited of Montreal.
Two flying prototypes of the aircraft, completely designed and developed by Canadair, are now in production with completion scheduled for the fall of 1958.
There have been frequent references over the past two years to Canadair activity on an ab initio jet trainer project. The company is known to have watched closely evolution of a Royal Canadian Air Force specification for an aircraft of this type. The Canadair design is said to have been highly rated by the RCAF in its continuing study of the breed.
Canadair engineers say the CL-41 incorporates all the desirable feature of a basic jet trainer to take the student from the ab initio through the basic flight training stages.
Features include: Side-by-side seating for the instructor and trainee ejection type escape seats; a jettison able canopy sequenced into the ejection escape system; cabin pressurization; complete instrumentation incluing two blind flight panels; a birdproof glass windshield.
The Canadair Trainer will be powered by a single turbo-jet engine of the latest light weight design and low specific fuel consumption. The static thrust of the engine will be in the order of 2,000 lb.
Canadian Engines?
There has evidently been no firm decision as to a power plant for either the prototypes or possible production aircraft. Existing and development turbojets which come closest to the CL-41's requirements include the Armstrong - Siddeley Viper, RollsRoyce R.B. 108, Fairchild J-44, Continental J-69 and General Electric J-85.
It is conceivable that the CL-41 might end up as an all-Canadian effort.
Canadian Pratt & Whitney Aircraft Co. Ltd. of Longueuil, Que., has its research and development section working on a small turbojet design project. Tle over-all plan is to have the Canadian company come up with, an engine which would supplement the U S. Pratt & Whitney stable of big turbojets and put P&W in a position to power any jet airframe. Theres little doubt that Canadian P&W will take a good look at CL-41 specifications in bringing its design along.
Orenda Engines Ltd. of Malton has demonstrated its competence in the original design field. With the Iroquois moving toward production, Orendas experienced design team is in an excellent position to tackle a small turbo jet project. The company's demonstrated ability at "making more lightness" could be employed to advantage in such an undertaking. The Malton firm has shown a definite interest in the possibility of providing the CL-41 powerplant.
Pertinent dimensional and performance data on the CL-41 are: Design gross weight 6,250 lb.; wing area 220 square feet; wing loading 28.4 lb. per square feet; thrust loading "static" 3.13; wing span 36 ft. 4 in.; length all-over 31 ft. 11 in.; height over-all 9 ft. 1/2 in.
Performance Data
Performance characteristics of the airplane are: take-off ground run 1,000 feet; take-off over 50 foot obstacle 1,700 feet; landing distance ground run 1,100 feet; landing distance over 50 foot obstacle 1,800 feet; stalling speed, intermediate weight 62 knots; maximum speed, military power, at intermediate weight 400 knots; maximum speed continuous power, intermediate weight 388 knots.
The fuel load is approximately 2,000 lb. This allows the airplane a two-hour training flight of circuit and landings at sea level without refueling.
At altitude, this same amount of fuel, less 10 percent for reserve, will give the aircraft a range of 800 nautical miles at an average speed of 300 knots.
A full-scale mock-up of the CL-41 been constructed as a check on the design arrangement. Representatives of the RCAF and U. S. Navy and Air Force have subjected the mock-up to a systematic review.
A one-fifth scale static model has thoroughly wind-tunnel tested extremely satisfactory results. Two one-fifteenth scale dynamic models have also been thoroughly tested in the spin tunnel of the National Aeronautical Establishment at Ottawa.
Results of the latter tests show the CL-41 spin and recovery characteristics, as indicated by the model, satisfy both British and U. S. criteria. Since the two criteria differ appreciably in basic approach, it is considered an that the CL-41 meets both.
The Jet Trainer Liaison Committee of RCAF has facilitated design by indicating RCAF opinion on technical questions posed by Canadair engineers, which means this aircraft meets with all RCAF needs.
Experience in other countries, particularly by the RAF in Britain, shows that it is quite feasible and even more economical to train pilots ab initio using an aircraft as large as the CL-41. Pilots would graduate from the ab initio CL-41 to the Canadair T-33 and thence to a transonic or super-sonic vehicle.
In summary, highlights of the new Canadair Trainer include its cabin pressurization, birdproof glass windscreen, advanced lightweight turbo-jet engine, maximum speed, short take-off and landing distances, and its training endurance of two hours of circuits and landings without refueling.
Preliminary design is now under way on the inclusion of an armament pack, not only for training but to give this multipurpose aircraft a practical ground support role.
In addition, there will probably be an eventual re-arrangement of the interior to make it a four-seater plane which can be used for many purposes.
The whole design program has been under the direction of W. K. Ebel. vice-president engineering, and E. B. Schaefer, chief engineer. E. H. Higgins is project manager while F. C. Phillips has been project engineer since the inception of the program.
Canadian Aviation, December 1957, p 46 47