THE PILOT SITS ON THE LEFT of the Tipsy and the passenger or flying instructor on the right. The passenger's seat is staggered backwards in relation to the pilot’s seat, so that the width of the fuselage will not have to be undesirably wide. An inverted Mikron engine of sixty-two horse-power permits the pilot an excellent forward view.
THE Tipsy two-seater light aeroplane is a unique aircraft. It is the only open side-by-side seating monoplane available in Great Britain at present. The prototype was designed by Ernest O. Tips, Manager of the Fairey Aviation Company’s Belgian factory, and the drawings were modified at the Fairey drawing offices at Hayes (Middlesex), to comply with the British Certificate of Airworthiness conditions. Tipsy aircraft are built under licence from the Fairey Aviation Company.
The two-seater Tipsy has been developed from the Tipsy single-seater monoplane which had a flat twin-cylinder engine. Good performance was a feature of this single-seater, which had a top speed of 108 miles an hour. This feature is. to be found also in the two-seater. Mr. Ernest Tips designed both the single-seater and the two-seater and the aircraft is named after the designer. Early in 1938 the production model of the Tipsy two-seater obtained a normal Certificate of Airworthiness. The design had been stressed for aerobatics and it was not anticipated that there would be much delay in obtaining a full aerobatic Certificate of Airworthiness.
The Tipsy is a low-wing monoplane with two seats arranged side by side in an open cockpit, which is situated above the wing. Clean lines are a noticeable feature and the width of the fuselage has been kept down to reasonable proportions by staggering the seats.
The passenger, or instructor, sits on the right of the pilot and about six inches farther back. Both occupants of the aeroplane are thus given ample elbow room. A four-cylinder in-line engine of the inverted type is fitted which considerably aids the clear vision obtained from the cockpit. Flaps are incorporated for steepening the angle of approach glides, and separate landing-wheel units are fitted. Spats are provided round the wheels. A single-piece elevator is used which runs below the rudder. The tail-skid is of the steerable type.
The aircraft combines many of the amenities of cabin aircraft with the advantages of an open cockpit. For those who prefer it, a cabin top to close in the cockpit is available. The control column is placed centrally in the fuselage and comes conveniently to hand from the pilot’s seat. When the aircraft is to be used for instructional purposes, an extension is attached to the control column to enable the aircraft to be flown from the right-hand seat.
The rudder controls are of the pedal type — a feature which helps to provide ample leg room. When a passenger is carried a footrest bar hinges up to prevent the passenger’s feet from coming into contact with the rudder pedals on the right-hand side of the machine.
The throttle and altitude controls are in the normal position to the left of the pilot. Below them is the tailtrim lever; by the instrument board is the control for the flaps. For instructional machines the second throttle is designed to go behind the main throttle so that the instructor reaches it with his left hand passing behind the pilot’s seat. This is the most comfortable position for his left arm at all times. Side-by-side seating has an advantage for instruction in that the instructor can watch a pupil’s reactions and movements.
Technically, the Tipsy has many points of considerable interest. The wings are built as one complete plane with a robust wooden-box-type main spar running the whole length. The ribs are also of wood and the leading edge of the plane is covered with plywood. The remainder is fabric-covered. The plane is quickly detached, being held to the fuselage by four bolts. When the wings are removed the control column comes away with them; this feature gives good access to the mechanism.
The fuselage is of conventional rectangular box construction. To obtain the rounded top to the fuselage, metal hoops are attached to the top of the fuselage box and joined across by stringers to which the fabric is attached. The landing wheels have a vertical movement of six inches provided by telescoping tubes. The spring action is obtained by compressing rubber pads with light metal disks between them. These pads fit into the larger of the two telescoping tubes. The rudder and ailerons are mass balanced. On the rudder the mass weight takes the form of an external weight. A modification to do away with this bobweight has, however, been devised.
Wings Removable in Four Minutes
The balancing of the ailerons is achieved by setting the hinges a short way back from the leading edges of the control surfaces and fitting the weights inside the fairing of the leading edges of the control surfaces. The springing of the tail skid is by means of laminations of bamboo.
The flaps are six inches wide and do not meet beneath the fuselage. They are pulled down by the lever in the cockpit against springs which return them to the closed position when the lever is moved back again. The tail fin is built integral with the fuselage. It is of wood, covered with plywood and finally with canvas. The canvas is put over the fin in the form of a bag. At the bottom of the bag the fabric is pulled out to the two top longerons of the fuselage box and doped into position so that an excellent smooth curve from fin to fuselage is obtained.
The fabric of the wings is attached in an unusual manner. When the wings are ready for covering, the points of contact of the fabric with the spars and ribs are first covered with glue. The fabric is then put into position and doped with thinners (a diluent for paints, varnishes and so forth) where it is to contact the glue. Finally pressure is applied by rubber rollers which force the fabric smoothly into contact with the glued ribs and spars.
Practicability of design has been given due consideration. For instance, the design of the windscreen is such that only the slightest draught is experienced, and the aircraft can be flown in any conditions without the use of goggles being necessary. Moreover, by means of the four-bolt fixing for the wings, they can be removed in four minutes. This is a valuable feature for storing when hangar space is limited.
The engine normally fitted is of Continental manufacture. It is a Walter Mikron of 62 horse-power. This maximum output is obtained at 2,800 revolutions a minute. The engine gives 60 horse-power at 2,600 revolutions a minute. Two Scintilla magnetos are fitted and two fuel pumps. The carburettor is a Walter-built Hobson.
A CENTRAL JOYSTICK IS USED, which can be reached from either seat. When the aircraft is used for instructional purposes, an extension is fixed to the joystick for use from the right-hand seat. For passenger flying a footrest hinges upwards to keep the passenger’s feet clear of the rudder pedals. The throttle control is in the normal position to the left of the pilot.
The normal petrol consumption at the cruising speed of 100 miles an hour, which is obtained with the engine running at 2,600 revolutions a minute, is three and a quarter gallons an hour. The specific fuel consumption is 250 grams (0.55 lb.) per brake-horse-power-hour. A petrol tank holding 13¼ gallons is fitted behind a fireproof bulkhead which separates it from the engine. The oil tank is fitted on the engine side of this bulkhead and holds one and three-quarter gallons.
The power loading of the aircraft is 17.9 lb. per horse-power. The range at cruising speed is about 350 miles. This is made possible by the low petrol consumption of the four-cylinder air-cooled engine. The aircraft will not always be flown at its maximum cruising speed; slightly slower speeds improve the petrol consumption figures. This is illustrated by a flight which was made from Brussels to Nice and back at an average speed of a little over 90 miles an hour. In both directions the petrol consumption averaged as little as 2.8 gallons an hour.
The span of the aircraft is 31 ft. 2 in., the length 21 ft. 8 in. and the height 7 feet. The wing area is 129 square feet. The empty weight is 618 lb. and the weight fully loaded is 1,074 lb. This includes 22 lb. of baggage, room for which is provided behind the seats. The wing loading works out at 8.3 lb. per square foot.
A top speed of approximately 110 miles an hour is obtainable. This is an excellent figure when the stalling speed of 37 miles an hour is borne in mind. The good speed-range ratio is due mostly to the clean design and only slightly to the flaps, which affect the stalling speed to the extent of only about three miles an hour. The Tipsy can reach a ceiling of 19,000 feet and has a climb of 650 feet a minute. The take-off run varies considerably with the speed of the wind, but an average figure is in the neighbourhood of 100 yards.
The best climbing speed is about 65 miles an hour; 45 to 50 miles an hour is about the best gliding speed for the approach. The flaps may easily be brought into use at speeds between 60 and 70 miles an hour.
Tractable in Rough Weather
The handling of the Tipsy in flight has been considered from the point of view of instruction and flying by inexperienced pilots as well as flying by experts. Most pilots consider it a fascinating aircraft to fly because of the lightness of the controls and because of their immediate effect on the attitude of the aeroplane. The steerable tail skid makes taxying easy and the aircraft is stable on the ground when taxying across, with or down wind.
The tail lifts quickly in response to the elevator when the pilot is preparing to take off, and the aeroplane may be pulled off the ground in a steep climb. As when on the ground, the Tipsy is tractable in the air during rough weather and its high speed gives a useful ground speed even against a strong headwind. Thus the aircraft is practicable for cross-country flying in all weathers.
Steep turns are simple to make and .the aircraft will rapidly change from a right-hand to a left-hand turn. A point about turns which the inexperienced pilot might find a little difficult is the position of the nose on the horizon. Because of the side-by-side seating, the nose is apparently a good way below the horizon in a right-hand turn and on or above the horizon in a left-hand turn. A pilot soon becomes used to the position of the joystick being offset to his right.
The loss of speed and control during the period before a stall is sufficiently gradual to warn any pilot of the approach of a stall, although the stall itself occurs quite briskly when a speed of 37 miles an hour is reached. Control is rapidly regained when the control column is eased forward to bring the machine out of a stall. The upward movement of the elevator is restricted: this prevents a sudden stall from being performed.
The flaps when applied do not vary the attitude of the aircraft considerably and are not therefore likely to prove disconcerting if the stick is not eased forward when they are applied. Moreover, they do not hamper a second take-off if a bad landing is attempted and a pilot wishes to make another circuit.
The restricted upward movement of the elevator assists the landing of the Tipsy. If the aircraft is brought in at a reasonable gliding speed it is possible to pull the stick right back before the aircraft is about to touch the ground and yet make a good landing.
A WELL-PROPORTIONED WINDSCREEN keeps the cockpit of the aircraft free from draught; a cockpit cover is available if desired. Balanced controls and trailing-edge flaps are incorporated the elevator is in a single piece. Springing for the steerable tail skid is by laminations of bamboo; rubber compression springing is used for the landing wheels.
