Flight, June 1929

OLYMPIA AERO SHOW 1929

The Breda 15 Monoplane

   Owing to the fact that the Olympia Show did not open until Tuesday of this week, and that these articles had to be prepared in advance, it has not, unfortunately, been possible to obtain very much information concerning some of the foreign machines exhibited. Among the machines to which this applies is the little Breda 15, exhibited in the annexe. The machine was on the stand when our representatives paid a visit, but there was no one present who could give detailed figures relating to the machine, and we have, therefore, to confine ourselves to giving the results of an external inspection.
   The Breda 15 is a high-wing monoplane two-seater, in which the occupants are accommodated in a small cabin under the wing. The fuselage is a plywood-covered structure, and there are two doors leading to the cabin. The pilot occupies the rear seat, and enters the cabin through a door on the port side. The passenger or pupil (the machine has dual controls) is provided with a door in the starboard side. As the deck fairing of the fuselage drops away in front of the windscreen, the view from the front cockpit is very good, although one would imagine that the, view from the rear seat is somewhat obscured by the passenger in front.
   The monoplane wings are attached to the top corners of the fuselage, and are arranged to be folded back. An undercarriage of the split type is fitted. The engine is a four-cylinder-in-line air-cooled. We hope to give weight and performance figures of the Breda 15 in next week's issue.

Flight, April 1930

AIRCRAFT FOR THE PRIVATE OWNER

BREDA

   INTERNATIONAL AIRCRAFT, LTD., of New Bond Street, London, W.I, are the sole concessionnaires for the Breda in this country, and they have recently imported two machines of this type from the Italian factory.
   The Breda is in its way a very interesting little machine. Its stalling speed is phenomenally low, even though its top speed is high and it is practically impossible to spin it.
   The cabin is arranged with the two seats in tandem, and although the pilot's cockpit has no windows at the sides - that is, no glass windows - pilots say that there is a complete absence of draught, making the machine particularly comfortable to fly.
   The machines over here have "Gipsy" engines fitted, which would appear to blanket the forward view somewhat owing to the high mounting, but apart from this the pilot should have no great difficulty over the view. In the front cockpit the windows may be slid aside as required. Access to the cabins is by doors, that to the front seat being on the starboard side, while that to the pilot's seat is on the port side.
   The wings are arranged to fold, it being only necessary to use a jury strut for the front bracing strut on each side and to fold up a small flap at the wing root to clear the cabin top.
   The equipment is exceptionally complete. Wheel brakes are fitted as standard, as are a dual set of instruments and controls, a centralised fire extinguisher system, and a compass.
   There is a large luggage compartment behind the pilot's cockpit with its own door opening on the port side of the fuselage.
   Wood is largely used for the construction, though steel tubes play an important part in the front fuselage. The rear fuselage is plywood covered, as are the wings and tail units.
   The Breda now has a divided axle undercarriage with rubber blocks of very large size in compression for the telescopic leg.
   The fuel is carried in two tanks, one in either wing root, a design which leaves the cabin roof clear, so that it can be glazed and allow the pilot an upward view.

Flight, October 1933

THE UGO ANTONI WING

   AMONG the many problems which face the aircraft designer, few are more important than speed range. A high operational speed is necessary if the aeroplane is to compete successfully with ground transport, and one way in which cruising speed can be raised is by cutting down wing area. Practical considerations soon place a limit on the degree to which wing loading, and consequently landing speed, can be increased. From several points of view a high wing loading is an advantage, and the problem then becomes one of finding means of raising the unit lift of the wing. One way of doing this is by using a hinged trailing-edge flap arranged so that it can be raised and lowered by the pilot. This system has been used by the Fairey Aviation Co. for many years with good results. Another way is to delay the breaking away from the wing of the air flowing over it until a larger angle has been reached. This is the object of the Handley Page lift slot. More recently researches have been carried out in the United States on "split" trailing-edge flaps, in which the upper half remains in line with the wing contour, while the lower half is hinged downwards.
   All these methods have advantages and disadvantages, but as the aerodynamic refinement of aeroplanes is increased, the need for devices which will not only increase the lift but also the drag, in order to provide a steeper gliding angle, becomes more urgent, and it is likely that in the near future aircraft with variable wings of some form or other will become a good deal more common than they are at present.
   As long ago as May, 27, 1932, we described and illustrated in FLIGHT a variable camber wing patented by the Italian engineer, Ugo Antoni. After failing to get the necessary support in Italy, Mr. Antoni came to England, where he has succeeded in obtaining financial assistance to continue the work which he started in Italy in 1907. He and his friends have established a company under the title Ugo Antoni Safety Aircraft, Ltd., with offices at 17, Thavis Inn, Holborn Circus. The Gloster Aircraft Co., Ltd., was, as mentioned in our article last year, entrusted with the construction of the first Ugo Antoni variable camber wing in this country, and as we recorded in FLIGHT a couple of weeks ago, the machine made its first test flights recently. With the exception that the existing rudder on the Breda monoplane on which the new wing has been mounted was found to be rather inadequate, the test flights were very successful, and a larger rudder has now been built and the flights are to be continued.
   The external appearance of the Ugo Antoni variable camber wing, as mounted on the Breda monoplane, is shown in our photographs, and most of the relevant details are illustrated by sketches. It will be seen that the camber mechanism does not extend over the entire wing span. At the tips the wing is of normal construction to allow of the use of the usual horn-balanced aileron. At the root there is also a fixed wing portion, but this has an upturned flexible trailing edge, the purpose of which is to give fore-and-aft stability. Between fixed and movable wing portions baffle plates are fitted in order to reduce the "spilling" of air over the ends of the movable wing when the camber is set at its maximum.
   The general principle of the camber gear is indicated by the diagrams at top and bottom of the previous page. The lower rib flanges are hinged to the bottom of the main spars, and cranks extend towards the centre of the wing chord, where they are joined together and to ties operated by cranks on the torque tube which operates the camber gear. The mechanism has a toggle action, and it will be seen that the toggle arm of the trailing edge portion is shorter than that of the leading edge. This results in a greater angular movement of the trailing than of the leading edge.
   The mechanical details of the camber gear are well shown in the sketches on the previous page. The ribs are of metal construction, while the main spars are of wood. The arrangement of the wing fabric has called for a good deal of thought, as it will be obvious that the covering on top of the wing must contract and expand as the camber is altered. The lower surface changes as much in camber as the top, but does not contract and expand to anything like the same extent, and the amount of contraction and expansion is taken care of by the small offset at A on the front spar.
   The arrangement of the fabric on the upper surface is ingenious. The main wing top fabric extends from the leading edge to just behind the rear spar, where it is attached to a wire running parallel with the spar. The top fabric covering of the trailing edge passes under the wire, and is attached to and moves with the trailing edge lower rib flange. The overlap of the two pieces of fabric is such that even at maximum camber no opening is left which might interfere with the airflow.
   In this first variable camber wing the designer has had to play for safety, and the result is that the wing is, perhaps, a little heavier than it need be. Thorough test flights will be made to decide this and other points, and there is little doubt that, in the next wing, detail structural improvements could be made. In the meantime, a wing has been produced which should serve to settle fairly definitely to what extent the variable camber wing is worth while, and if the advantages claimed by the designer are found to be realised or realisable, an excellent foundation has been laid upon which to base future development work.
   The fact that the wing has been built by the Gloster Company is sufficient guarantee that the workmanship is of a high order.