The Bulté RB.1 was a Belgian training and touring

biplane A biplane is a fixed-wing aircraft with two main wings stacked one above the other. The first powered, controlled aeroplane to fly, the Wright Flyer, used a biplane wing arrangement, as did many aircraft in the early years of aviation. While ...

first flown in 1928. Five examples flew with clubs and with private owners in contests and rallies.

Design and development

Until June 1928 Renée Bulté had been head of design with Ateliers de Construction Aéronautique de Zeebruges, usually known as ZACCO and one of the pioneers of all-metal aircraft manufacture. He left them to found his own company, Avions Bulté & Cie. Its first product, the RB.1 tandem seat

training aircraft A trainer is a class of aircraft designed specifically to facilitate flight training of pilots and aircrews. The use of a dedicated trainer aircraft with additional safety features—such as tandem flight controls, forgiving flight characteristic ...

, flew towards the end of the year. The RB.1 was a simple, conventional, two-bay biplane with thin-section, equal span wings mounted without stagger. One feature of the design was the interchangeability of components; as an example, the wing panels were identical. Such interchangeability reduced the stocks of spares required. The lower wings were attached to the lower fuselage structure and the upper ones to a fuselage-wide centre section held well above the fuselage by four upright

cabane strut In aeronautics, bracing comprises additional structural members which stiffen the functional airframe to give it rigidity and strength under load. Bracing may be applied both internally and externally, and may take the form of struts, which act in ...

s from the upper fuselage. Both upper and lower wing-sets were mounted with 3° of dihedral and were braced together with two pairs of identical, parallel

interplane strut In aeronautics, bracing comprises additional structural members which stiffen the functional airframe to give it rigidity and strength under load. Bracing may be applied both internally and externally, and may take the form of struts, which act in ...

s on each side, assisted by the usual wire cross-bracing. Both had short, broad- chord

ailerons An aileron (French for "little wing" or "fin") is a hinged flight control surface usually forming part of the trailing edge of each wing of a fixed-wing aircraft. Ailerons are used in pairs to control the aircraft in roll (or movement around ...

which reached the wingtips and were externally interconnected. Structurally, each wing was built around two

spruce A spruce is a tree of the genus ''Picea'' ( ), a genus of about 40 species of coniferous evergreen trees in the family Pinaceae, found in the northern temperate and boreal ecosystem, boreal (taiga) regions of the Northern hemisphere. ''Picea'' ...

spars SPARS was the authorized nickname for the United States Coast Guard (USCG) Women's Reserve. The nickname was derived from the USCG's motto, "—"Always Ready" (''SPAR''). The Women's Reserve was established by law in November 1942 during Wor ...

and had

plywood Plywood is a composite material manufactured from thin layers, or "plies", of wood veneer that have been stacked and glued together. It is an engineered wood from the family of manufactured boards, which include plywood, medium-density fibreboa ...

-covered leading edges. The trainer was powered by an Anzani 6 six-cylinder

radial engine The radial engine is a reciprocating engine, reciprocating type internal combustion engine, internal combustion engine configuration in which the cylinder (engine), cylinders "radiate" outward from a central crankcase like the spokes of a wheel. ...

in the nose, fitted with a narrow-chord ring

cowling A cowling (or cowl) is the removable covering of a vehicle's engine, most often found on automobiles, motorcycles, airplanes, and on outboard boat motors. On airplanes, cowlings are used to reduce drag and to cool the engine. On boats, cowlings ...

. Immediately behind the engine the fuselage was five-sided, rectangular below but sloping on top, and was covered with

aluminium Aluminium (or aluminum in North American English) is a chemical element; it has chemical symbol, symbol Al and atomic number 13. It has a density lower than that of other common metals, about one-third that of steel. Aluminium has ...

sheets back to the wing leading edge. This region contained both fuel and oil tanks. Behind it, the fuselage was formed around four wooden longerons,

ash Ash is the solid remnants of fires. Specifically, ''ash'' refers to all non-aqueous, non- gaseous residues that remain after something burns. In analytical chemistry, to analyse the mineral and metal content of chemical samples, ash is the ...

to the rear of the

cockpit A cockpit or flight deck is the area, on the front part of an aircraft, spacecraft, or submersible, from which a pilot controls the vehicle. The cockpit of an aircraft contains flight instruments on an instrument panel, and the controls th ...

and spruce further aft. The ash-framed part had three-ply covered sides and a thin

underside and the rear fuselage was canvas covered, including domed rear decking. Normally the instructor and student sat one behind the other in a long, single, open cockpit, equipped with dual control. The front seat was under the wing but the rear one was behind the

trailing edge The trailing edge of an aerodynamic surface such as a wing is its rear edge, where the airflow separated by the leading edge meets.Crane, Dale: ''Dictionary of Aeronautical Terms, third edition'', page 521. Aviation Supplies & Academics, 1997. ...

, which had a rectangular cut-out for better upward vision. Alternatively, the seats could be arranged tightly side-by-side, though with slight stagger, which allowed single controls to be shared and eased communication. The RB.1's

empennage The empennage ( or ), also known as the tail or tail assembly, is a structure at the rear of an aircraft that provides stability during flight, in a way similar to the feathers on an arrow.Crane, Dale: ''Dictionary of Aeronautical Terms, third ed ...

was conventional, with a broad-chord, rectangular plan

tailplane A tailplane, also known as a horizontal stabilizer, is a small lift (force), lifting surface located on the tail (empennage) behind the main lifting surfaces of a fixed-wing aircraft as well as other non-fixed-wing aircraft such as helicopters ...

mounted on top of the fuselage and carrying

elevator An elevator (American English) or lift (Commonwealth English) is a machine that vertically transports people or freight between levels. They are typically powered by electric motors that drive traction cables and counterweight systems suc ...

s with a large central cut-out for

rudder A rudder is a primary control surface used to steer a ship, boat, submarine, hovercraft, airship, or other vehicle that moves through a fluid medium (usually air or water). On an airplane, the rudder is used primarily to counter adverse yaw ...

movement. Its triangular

fin A fin is a thin component or appendage attached to a larger body or structure. Fins typically function as foils that produce lift or thrust, or provide the ability to steer or stabilize motion while traveling in water, air, or other fluids. F ...

mounted a parallelogram profile rudder which reached down to the keel. It had conventional, fixed

landing gear Landing gear is the undercarriage of an aircraft or spacecraft that is used for taxiing, takeoff or landing. For aircraft, it is generally needed for all three of these. It was also formerly called ''alighting gear'' by some manufacturers, s ...

, with its mainwheels on a single axle and a wide track of about . The axle was joined through rubber cord shock absorbers to a fixed pair of transverse steel tubes supported by a pair of steel V-struts mounted on the lower fuselage longerons. Its tailskid was externally mounted on a little steel tube pyramid, with a knee-type rubber cord shock absorber.

Operational history

The Bulté RB.1 first flew towards the end of 1928, though the exact date is not known. Five appeared on the Belgian civil aircraft register between 1929 and 1931. One took part in the ''Tour du France des Avions de Tourisme'' around France in May 1931 and another in the

Auvergne Auvergne (; ; or ) is a cultural region in central France. As of 2016 Auvergne is no longer an administrative division of France. It is generally regarded as conterminous with the land area of the historical Province of Auvergne, which was dis ...

rally in July that year. In the UK sales efforts were handled by Sealandair but no examples were registered.

Specifications (RB.1)

References

{{reflist, 2, refs= {{cite journal , last=Frachet , first=André , date=8 November 1928 , title=L'avion-école Bulté R.B.1, journal=Les Ailes, issue=386 , pages=3, url=http://gallica.bnf.fr/ark:/12148/bpt6k6554616z/f3 {{cite journal, date=7 May 1931 , title=Le tour du France des avions de Tourisme, journal=Les Ailes, issue=516 , pages=13–15, url=http://gallica.bnf.fr/ark:/12148/bpt6k65557653/f15 {{cite journal, date=9 July 1931 , title=Portal à gagné le rally Auvergne, journal=Les Ailes, issue=525 , pages=6, url=http://gallica.bnf.fr/ark:/12148/bpt6k65557742/f6 {{cite journal , date=27 June 1930 , title=A Belgian training machine, journal=

Flight Flight or flying is the motion (physics), motion of an Physical object, object through an atmosphere, or through the vacuum of Outer space, space, without contacting any planetary surface. This can be achieved by generating aerodynamic lift ass ...

, volume=XXII , issue=29 , pages=678 , url= https://www.flightglobal.com/pdfarchive/view/1930/untitled0%20-%200718.html {{cite web , url=http://www.airhistory.org.uk/gy/reg_OO-.html, title=Golden Years of Aviation , author= , date= , work= , publisher= , accessdate=15 August 2017 {{cite web , url=http://publicapps.caa.co.uk/modalapplication.aspx?appid=1, title=GINFO Database Search , accessdate=15 August 2017 1920s Belgian aircraft