Three classes of Trainers - primary, single-engines and twin-engines - are used to train British pilots
A HIGH-PERFORMANCE MONOPLANE for advanced training to be used in the Royal Air Force. It is the Miles R. R. Trainer, and is fitted with a Rolls-Royce Kestrel engine and a three-bladed controllable-pitch propeller. Two seats are provided and the aircraft is to be used for the training of fighter pilots. A maximum speed of nearly 300 miles an hour is attainable.
TRAINING aircraft in the Royal Air Force have a task to perform which is somewhat different from that of trainers for private , and commercial flying. Not only have R.A.F. pilots to be taught how to fly and navigate like all other pilots, but they have also to learn to fight.
Some of the trainers which are used for elementary tuition are similar to trainers used in flying clubs and schools, but the advanced trainers are nearly the same as certain Service aircraft. In some instances the trainers are identical with Service types, except that they are made suitable for training by a few additions such as dual controls.
There are so many different types of Service aircraft that it would not be possible to have a training counterpart of each one. But the trainers used are sufficiently representative of their class of aeroplane to enable pilots to do all their training on them up to the stage where they join a Service squadron. After having joined their squadron they may have to do a little training to become used to the Service types which they are to fly.
As Service types of aircraft change, so the types of trainers have to change. The object is to train pilots on aircraft which exhibit the same characteristics and which require the same flying technique as Service machines. The change which is taking place in the Royal Air Force from biplane fighters to the new low-wing fighters, such as the Hurricane, provides an excellent example of this. Low-wing trainers, such as the Magister, are being introduced, even for elementary training. Thus, right from the beginning of his training, the pilot becomes accustomed to the flat glides of modern aircraft and to the methods of using flaps to assist approach to an aerodrome and the landing.
In private flying it is likely that the pilot will do most of his flying when qualified on the same type of aircraft as that on which he learns. Thus there is much in favour of teaching him on types particularly easy to fly. For Service training aircraft should not be too easy to fly; otherwise time will be wasted in the transition period from trainer to Service type. All elementary Service trainers have a full Certificate of Airworthiness; that is to say, they may be used for aerobatics. Spinning is taught in the early part of elementary training.
Although trainers must not be too easy to fly, they must not exhibit any vices with which the trainee, at the stage of his progress at the time when he flies a particular trainer, is not competent to cope. This qualification applies mostly to elementary trainers.
Another requirement in elementary trainers is great strength in such items as the undercarriage. When landings are taught pupils must be allowed to make mistakes so that they may learn from them. Their mistakes place a heavy load on the undercarriage. Similarly poor landings during the early stages of solo flying often cause great strain to be placed on the undercarriage. All trainers, whether of elementary or advanced types, must be provided with dual control.
R.A.F. trainers may be divided into three classes — elementary or primary trainers, single-engined advanced trainers and twin-engined advanced trainers.
Except for cadets being trained at Cranwell for permanent commissions, all elementary training is conducted at civil flying schools. These schools are exclusively confined to training for the Air Ministry and employ ex-Service instructors. Elementary training covers the handling of aircraft without any emphasis on its use as a fighting weapon. That is why the elementary trainers are similar to aircraft to be found in many civil flying schools.
There are two types of elementary biplane trainers which have been in use some time. They are the De Havilland Tiger Moth and the Avro Tutor. A more recently added type of trainer is a monoplane, the Miles Magister. As more and more Service types become monoplanes more and more elementary trainers will doubtless be monoplanes. The De Havilland Tiger Moth is a development of the previous open two-seater Moth aircraft such as the Gipsy Moth and the Moth Major. Its biggest characteristic difference is that the wings slant backwards slightly instead of being straight. It is at present the only two-seater open aircraft of De Havilland design.
Sensitive on the Controls
The Tiger Moth is the smallest of all the trainers used in the Royal Air Force. It has a wing span of 29 ft. 4 in. and a length of 23 ft. 11 in. The length as a seaplane of the float type, in which form the Tiger Moth is used also, is 25 ft. 5 in. The height as a landplane is 8 ft. 9½ in. The seaplane version is a little higher.
The Tiger Moth is a two-seater biplane with open cockpits, one behind the other. The pilot’s cockpit is normally the back one, from where the visibility is less interfered with by the wings. The pupil sits in the back cockpit when being trained.
A 130 horse-power Gipsy Major engine is fitted. This engine is made by the makers of the aircraft. It is an air-cooled four-cylinder in-line engine of the inverted type. The maximum speed of the aircraft at sea level is 109 miles an hour. The absolute ceiling is 16,000 feet and the stalling speed is as low as 45 miles an hour. In spite of this low stalling speed, the aircraft has a reasonably steep glide and short landing run. It is sensitive on the controls — a characteristic which ensures that the pupil trained in this type of machine will develop “good hands”.
The second of the two biplane trainers is the Avro Tutor. Like the Gipsy Moth, this aircraft is the descendant of a long line of successful biplanes. Avro biplanes have played a wide part in training pilots since the Gosport system of training was introduced during the war of 1914-18 (see the chapter “Training Machines”).
The seating arrangements of the Avro Tutor are similar to those of the Gipsy Moth. The wing span is 34 feet and the length 26 ft. 6 in; the height is 9 ft. 7 in. There is a pronounced stagger of the wings, the upper plane being considerably in advance of the lower plane.
THE INTRODUCTION OF MONOPLANES in large numbers into the equipment of the R.A.F. has made monoplane primary trainers necessary. The pilots thus become accustomed from the beginning to the flying technique required by modern monoplanes. The aircraft in this photograph is a Miles Magister; it has a Gipsy Major engine and a maximum speed of 145 miles an hour.
A radial type of air-cooled engine is fitted. It is a seven-cylinder 215 horsepower Armstrong Siddeley Lynx. The Avro Tutor is somewhat larger than the Gipsy Moth, and requires a more powerful engine. But the additional horse-power is sufficient to give the aeroplane a higher performance. The maximum speed is 122 miles an hour and the landing speed is 45 miles an hour. The service ceiling is 15,000 feet.
The aircraft is unusually stable in rough weather for this class of aeroplane. This has the advantage that tuition in an Avro Tutor may continue at times when other elementary trainers may have to stay on the ground. The airframe is of metal construction; when Handley Page slots are fitted, a locking device to put them out of action is provided in each cockpit.
The Miles Magister, manufactured by Phillips and Powis Aircraft Ltd., represents the modern practice in aircraft design. This trainer has been developed from similar designs over a period of five years from 1933. The first of these was the Miles Cirrus Hawk. Then came the Miles Hawk Major, with a more powerful engine and the addition of flaps. A machine known as the Miles Hawk Trainer Mark II was interposed between the Miles Hawk Major and the Magister.
The Magister is a low-wing monoplane fitted with wheel brakes and streamlining to the wheels. It is a cleanly designed aircraft, the trailing edge flaps being introduced to reduce landing speed and steepen the glide of the approach.
The power unit is the 130 horsepower Gipsy Major, the same engine as that fitted to the Tiger Moth. In view of this similarity in the engines used, it is interesting to compare the performance figures. The maximum speed of the Magister is 145 miles an hour at 1,000 feet — 36 miles an hour faster.
Service Ceiling 18,000 Feet
The landing speed — 45 miles an hour — is the same. This landing speed is obtained only with the flaps fully in use and the sink is much faster than on a biplane. This calls for a slightly different technique in judging the movement of the control column when making a landing. The service ceiling is 18,000 feet. The wing span is 33 it. 10 in., the length 25 ft. 3 in. and the height 6 ft. 8 in. The airframe of the Magister is built entirely of wood and is covered with plywood.
On completion of his elementary flying training, the R.A.F. pilot goes to a Service flying training school. At this stage he is transferred to Service-type trainers. Before the pupil begins his advanced training a decision is made whether he is to fly single or twin-engined aircraft when he reaches his squadron (see the chapter “Training RAF Pilots”). He will then do all his advanced training on single-engined or twin-engined types.
At present the single-engined advanced trainers are biplanes of a type similar to that of many Service aircraft. They are Hawker Hart Trainers and Hawker Hind Trainers. A new monoplane trainer of advanced type which exhibits characteristics similar to those of modern fighters such as the Hurricane and Spitfire has been ordered in large numbers and will soon be in use. It is the Miles R.R. Trainer.
The Hawker Hart is a design from which a large number of single-seater and two-seater military aircraft have been developed. It is thus an ideal trainer for pilots who are going to fly the types of aircraft developed from it.
A TWIN-ENGINED ADVANCED TRAINER, the Airspeed Oxford, which closely resembles the Airspeed Envoy commercial passenger aircraft. The Oxford has two Armstrong Siddeley Cheetah X seven-cylinder radial engines, each rated at 350 horse-power at 7,500 feet. A crew of three is carried and the aircraft can be adjusted for various forms of training. The maximum speed is about 183 miles an hour at 10,000 feet The stalling speed is 64 miles an hour.
The Hart Trainer is adapted from the Hart day bomber at one time in use in the Royal Air Force. The military equipment is removed and complete dual control added. A Rolls-Royce Kestrel X engine of 635 horsepower is fitted. The Hart Trainer is an unequal-span biplane, the wings being staggered. The wing span is 37 ft. 4½ in. and the length of the aircraft 29 ft. 4 in. The overall height is 10 ft. 4 in. The wing and fuselage structure is of metal covered with fabric. Tandem cockpits are provided, the pilot being in the front one. There is a portion cut out of the trailing edge of the upper plane to improve the pilot’s view. The Rolls-Royce Kestrel X engine gives the aircraft a top speed of 184 miles an hour. The ceiling is 22,000 feet.
The Hart is one of the most widely used trainers in the Royal Air Force and is characterized by a rapid climb. The climb to 10,000 feet can be achieved in seven minutes. The undercarriage is of the type with a cross axle joining the two wheels.
The Hawker Hind Trainer is a training version of the Hind light day bomber in service in the Royal Air Force. This day bomber is a development of the Hart day bomber, but is fitted with a super-charged Rolls-Royce Kestrel V engine, instead of the Kestrel X. It incorporates a number of improvements suggested from long experience with the Hart day bomber.
The cockpits are arranged one behind the other in the Hind Trainer, the pilot sitting in the front cockpit, not in the back cockpit, as on elementary trainers. The aeroplane is a biplane in which the lower plane is shorter than the upper. The dimensions are as follows: span of upper wing 37 ft. 3 in., Length 29 ft. 7 in. and height, 10 ft. 7 in. The twelve-cylinder water-cooled engine has the cylinders arranged in V formation. The radiator, below the fuselage, is retractable; this enables the pilot to adjust the temperature. The power developed by the engine is a maximum of 640 horse-power at 14,000 feet.
The performance varies slightly according to the military equipment carried; for training purposes this will vary and will differ from the normal military load. The performance figures, however, may be taken as approximately the same as those of the Hind Bomber. The maximum speed is 187 miles an hour for the Hind Bomber at 13,120 feet.
The Miles R.R. Trainer, which is coming into service, is a low-wing cantilever monoplane of high performance. It can fly at a maximum speed of 295 miles an hour. This speed is attained at a height of 16,500 feet. This machine is built entirely of wood. It is provided with two seats, one behind the other; detachable covers are supplied for the cockpits. The stubs of the wings slope downwards from the fuselage, and the wings are provided with split trailing-edge flaps. The wheels retract completely into the wings by a special action which turns them and raises them backwards. The wing span is 39 feet and the length of the aircraft is 30 feet. The height when the wheels are lowered is 10 feet.
A water-cooled engine — the twelve-cylinder Rolls-Royce Kestrel XVI — is fitted. This engine drives a three-bladed controllable-pitch propeller and develops a maximum of 745 horse-power at 14,500 feet.
The service ceiling is 30,000 feet and the stalling speed is 62 miles an hour. The landing speed is, therefore, also in the neighbourhood of 62 miles an hour. It is apparent from the performance of the aircraft that considerable skill is necessary to fly it, and that it should provide excellent training for the high-performance fighters of to-day. Although the aircraft has been designed as a high-performance trainer, it may be considered as a suitable design for a general-purpose machine for fighting, light bombing or reconnaissance duties.
MODERN COUNTERPART of older Avro training aircraft, the Avro Tutor is a two-seat primary trainer of the biplane type. One of the characteristics of the Tutor is that it is particularly stable in rough weather conditions. The 215 horse-power Armstrong Siddeley Lynx seven-cylinder radial air-cooled engine gives the aircraft a maximum speed of 122 miles an hour. The landing speed is 45 miles an hour.
Two types of twin-engined trainers are used. One is the Avro Anson Trainer and the other the Airspeed Oxford. Both these aircraft are available as commercial passenger aircraft, in which form they are known as the Avro 652 and the Airspeed Envoy. There are, however, many differences between the commercial and military versions.
When used as a Service aircraft, the Anson is a coastal reconnaissance machine. It is a low-wing monoplane with the engines fitted on the wings on either side of the fuselage. When used in trainer form, dual control is added and flaps are also normally fitted. The wings are made of wood and covered with “Bakelite” plywood. The fuselage has a metal frame and is fabric covered over wooden fairings.
The wing span is 56 ft. 6 in., the height 13 ft. 1 in. and the length 42 ft. 3 in. The wheels are fitted to separate retracting units, one under either engine nacelle into which the wheels retract. The two engines are Armstrong Siddeley Cheetah IX air-cooled radials. Each of these engines develops 310 horse-power at 2,100 revolutions a minute at 6,000 feet. Each engine installation is entirely independent, as it is provided with its own petrol and oil tanks.
Radio operator’s and navigator’s positions are immediately behind the pilots’ seats. A bomb-aiming position is provided in the extreme nose of the fuselage.
The maximum speed of the aircraft is obtained at about 7,000 feet, and is 188 miles an hour. The service ceiling is 19,500 feet. Without flaps the landing speed is 62 miles an hour, but when flaps are fitted this is reduced to 57 miles an hour.
The Airspeed Oxford resembles the Avro Anson, in that it is also a low-wing twin-engined mono-plane. The engines are also mounted in the wings on either side of the fuselage. There is a gun turret on top of the fuselage at the back of the cabin. The undercarriage is of the retractable type and wheel brakes are fitted. The wings have Handley Page slotted ailerons and split trailing edge flaps are built into the wings.
An Adaptable Trainer
Although a crew of more than three is not carried, alternative positions for them are provided, so that various training purposes may be served. The positions are for pilot, navigator or second pilot, bomb-aimer, radio operator and rear gunner. By adjusting the seating and the equipment carried, the aircraft may be used for the following training duties: navigation, including night flying, radio operating and direction finding; bombing, including high flying with oxygen in use; air gunnery; aerial photography and training pilots in twin-engine flying. The two engines are 350 horse-power Armstrong Siddeley Cheetah Xs. These are air-cooled radial engines fitted with Townsend rings. The aircraft is 34 ft. 3 in. long and 9 ft. 9 in. high; it has a wing span of 53 feet. The speed at 10,000 feet is 183 miles an hour. The stalling speed is 64 miles an hour. With both engines in use the service ceiling is 23,000 feet, but on one engine the aircraft can climb to 6,000 feet.
The types of aircraft in the foregoing descriptions cover all the trainers in use in the R.A.F., but there are a number of other aircraft used at times for special training purposes. In many instances these other types are normal Service designs, being used for introducing pilots to special techniques. Among these may be included the aircraft in which pilots of flying-boat squadrons learn to bring aircraft down on water instead of on land.
Aircraft of types other than the normal trainers are used also to instruct pilots of the Fleet Air Arm in the flying of catapulted machines and in deck landings. Normally, all Service training aeroplanes are painted a bright yellow. This enables other pilots to recognize them quickly, and to make the necessary allowance for the comparative inexperience of the pilots who are flying them.
DUAL CONTROL IS FITTED to the Hawker Hind in its training form. The Hawker Hind Trainer is substantially the same as the Hawker Hind day bomber although the military equipment may vary. The Rolls-Royce Kestrel V twelve-cylinder engine is rated at 640 horse-power at 14,000 feet. The speed at 13,120 feet is 187 miles an hour and the aircraft can climb to 6,560 feet in four minutes.