Derived from the MB.50 Pipistrelle and MB.60 Barbastrelle, the two-seat cabin MB.70 was built to meet the requirements of the Service de l’Aviation Legere et Sportive.
It obtained its Certificat de Navigabilite in July 1950.
Prototypes of three versions were built, differing only in the type of engine installed.
MB.70 Engine: Salmson 9ADB, 45 hp Wing span: 33 ft 11 in Seats: 2
MB.71 Engine: Minie 4 DC32, 75 hp Wing span: 33 ft 11 in Length: 21 ft 4 in Height: 8 ft 2 in Empty weight: 765 lb Loaded weight: 1212 lb Max speed: 101 mph Cruise: 89 mph ROC: 787 fpm Seats: 2
MB.72 Engine: Continental A65, 65 hp Wing span: 33 ft 11 in Seats: 2
Maurice Brochet formed Constructions Aeronautiques Maurice Brochet and designed the MB.60 Barbastrelle tandem two-seat high-wing monoplane which first flew in June 1949.
Brochet MB.50 Pipistrelle at Chavenay airfield near Paris in May 1957
The first postwar design of Maurice Brochet was the MB.50 Pipistrelle (“Bat”) of 1947, which first flew that year. It is a single-seat open-cockpit ultra-light aircraft with a pylon-mounted high wing, wooden fuselage frame and fabric covering. The design was kept simple with the amateur-built market, using factory working drawings, in mind.
The first MB.50 was built in 1947 by Maurice Brochet and was powered by a Salmson 9ADb 45 h.p. radial engine. The subsequent Pipistrelles were all built by amateur constructors. In 1965, six were active, three powered by the Salmson, two by the Beaussier 4Bm O2 of 45 h.p. and one fitted with a Zlín Persy II.
Pipistrelle F-PEBZ was still active in 2005. Another was held in the collection of Ailes Ancienne Toulouse, near Toulouse Blagnac International Airport, during 2006.
Engine: 1 × Salmson 9ADb, 30 kW (45 hp) Wingspan: 8.00 m (26 ft 3 in) Length: 5.80 m (16 ft 0 in) Empty weight: 240 kg (529 lb) Gross weight: 351 kg (772 lb) Maximum speed: 140 km/h (87 mph) Cruising speed: 115 km/h (72 mph) Crew: One pilot
Derived from the MB-20, the 1934 Brochet MB-30, called the “Little Pike”, was basically the MB-20 with a tractor engine.
The type 20 took a different configuration although the aerodynamic set remains identical. The MB.30 was a parasol-wing monoplane of all-wooden construction.
Designed by Maurice Brochet, the single-seat sports aircraft first flew on 11 September 1934.
Brochet built three MB.30 in 1934 before opening the factory.
Engine: 1 × Poinsard 25hp, 19 kW (25 hp) Wingspan: 10.0 m (32 ft 10 in) Wing area: 13.5 m2 (145 sq ft) Length: 6.0 m (19 ft 8 in) Empty weight: 190 kg (419 lb) Gross weight: 300 kg (661 lb) Maximum speed: 105 km/h (65 mph, 57 kn)
The Avia 50 MP (ex MB-20), built by Maurice Brochet in Neauphle-le-Château
Maurice Brochet, former coachbuilder, recovered in 1931 a wreck of an Avia XVa. In his workshop at Neauphle-le-Château, he built a new fuselage with a central pylon on which he fixed a 25 horsepower Poinsard engine. The engine weighs only 35 kg. A single seater, the wing is high and guyed by two masts on each side.
Poinsot 25 CV
Even before the end of the construction, Brochet had designated his future motorglider MB-20. The aircraft was announced by Les Ailes in May 1933.
MB-20 under construction
A Jarlaud and Massenet visited Maurice Brochet, while the aircraft was still under construction. Attracted by the project, they bought the machine for 15,000 francs on behalf of the Aero-Club of Paris, and sign with Brochet a serial construction protocol. An engineer, Jarlaud modifies it to use the maximum of Avia parts.
After discussion, it was agreed that the device will be called “Avia-50”, however, this organization, represented by both visitors, were to bear the cost of testing the machine.
The first flight was on the morning of May 17, 1934, at Toussus-Paris, piloted by Eric Nessler. It started with three small hops at 7 or 8 meters high, soon followed by a real flight at 150 meters for ten minutes.
Eric Nessler at the helm of Avia 50 # 1 (ex MB-20,). At his side (with the beret) Maurice Brochet
After the flights of Eric Nessler, Albert Monville flew the motor-glider. After his flight, his impressions were as follows: “It’s really a glider, which is flying as such, and not an airplane. Glider pilots will be comfortable aboard this aircraft; they will soon be familiar with them. “
Georges Abrial then tested the machine after Albert Monville.
The propeller, poorly adapted, rotated too fast and a new propeller was prepared.
The aircraft was tested in the wind tunnel at Lille, January 5, 9 and 11, 1935, completed by a test of June 25 of the same year, without the wheels, totaling 3:30 hours of tesing.
An Avia 50 is built in 1934 by the “Aeronautical Constructions Letord et Cie” in Meudon. It has a fuselage redesigned. This motorglider was exhibited at the AéCDS show at the 1934 fair.
Avia 50 n ° 2. This copy was not built by Brochet
Les Ets Louis, in Pantin, built at least one Avia 50.
At the beginning of 1936, the AVIA lent its Avia 40 MP to the C.A.U. (Club Aéronautique Universitaire) for the training of its trainees B or C. It was present at the Vincennes meeting on May 23, 1937, piloted by Clamamus.
Avia 50 MP
The AVIA 50 MP was flown to Banne d’Ordanche and used for training. It was crashed by Emile Manduech during one of these courses. During late 1936 at Banne Ordanche, this aircraft was crashed by André Costa, following a loss of speed. The fuselage was broken, but the driver unscathed.
Bonnet in Bordeaux, Joly in Beaune, Leroy in Evreux, Botali in Paris and Brochet de Neauphle le Château, built the first motor-glider “Avia 50”.
Engine: 25 hp Poinsard Wingspan: 11,90 m Length: 6,72 m Height: 2,10 m Take off run: 10 sec Speed: 100 kph Range: 300 km
Single seat twin engined mid wing monoplane with conventional three axis control. Wing has unswept leading and trailing edges, and constant chord; T tail. Pitch control by fully flying tail; yaw control by fin mounted rudider; roll control by one third span ailerons; control inputs through stick for pitch/roll and pedals for yaw. Cantilever wing; wing profile Worthmann FX 63 137; double surface. Undercarriage has two wheels in tandem with wing tip skids; steel spring suspension on tailwheel and oleo-pneumatic suspension on main wheels. Push right go right tailwheel steering connected to yaw control. Brake on main wheel. Glass fibre/Kevlar fuselage, totally enclosed. Engines mounted above wing driving tractor and pusher propellers. Wing and T tail are also made with carbon and glass fibre, Kevlar and Dacron covered. A twin engined push pull aircraft, the Epervier descends in a direct line from his earlier Libellule. This prototype is a cross-country microlight, capable of covering 522 mile (840km) on one engine at economic cruise. The consumption of the Konig SC340 tri cylinder is 1.6 US gal/h (1.3 Imp gal/h, 6.0 litre/h) with the Epervier cruising at 40mph (65 kph). The Epervier can also be regarded as a motor glider with a glide ratio of 20/1 at 34 mph (55 kph), thanks to its Worthmann FX63 137 wing profile combined with a NACA0012 profile for the empennage. In addition to the ailerons, this wing is also fitted with three position flaps acting as flaps at 2o and 15 o and air brakes at 70 o camber. The construction of the prototype, designed at the end of 1981, was first seen during the summer of 1982, the first flight being made in May 1983.
At the European microlight salon at Lyon Bron in September 1982, Bernard Broc showed the prototype of the new single seat three axis microlight, this time with a T tail. As Aviasud had earlier given the name of Libellule MkII to the prototype which was destined to become the Sirocco, Bernard decided on the spot that he would name the machine Libellule MkIII to prevent confu¬sion. Retaining the Fledge wing of his earlier model, the Libellule Mk.III not only acquired a T tail but also a totally enclosed cabin. Bernard tells us he intends to replace the existing wing with a mid mounted cantilever design of composite construction and a Worthmann FX63 137 profile, which is very deep and gives high lift, with the aim of improving the glide angle to around 22/1. This project gave rise to the prototype Epervier twin engined aircraft. Single seat single engined high wing mono¬plane with conventional three axis control. Wing has swept back leading and trailing edges, and constant chord; T tall. Pitch control by fully flying tail; yaw control by fin mounted rudder and tip rudders; roll control by one third span spoilers; control inputs through stick for pitch/roll and pedals for yaw. Wing braced from above by kingpost and cables, from below by cables;; double surface. Undercarriage has three wheels in tricycle formation with additional tailskid; steel spring suspension on nosewheel and glass fibre suspension on main wheels. Push right go right nosewheel steering con¬nected to yaw control. Brake on nosewheel. Glass fibre fuselage totally enclosed. Engine mounted below wing driving pusher propeller. Epoxy, polyester and glass fibre for T tail and supporting boom. The Libellule MkIII has the option of a 26 hp JPX PUL425 engine in place of the 24 hp Konig SC430. Our data is based on the latter version. The Libellule MkIII is only produced in small numbers, availability being limited to 15 machines per year maximum in 1983.
Engine: Konig SC430, 24 hp at 4200 rpm. Propeller diameter and pitch 43 x 24 inch, 1. 10 x 0.60 m. No reduction. Power per unit area 0.15hp/sq.ft, 1.6hp/sq.m. Fuel capacity 6.6 US gal, 5.5 Imp gal, 25.0 litre. Length overall 19.8 ft, 6.00 m. Height overall 8.2ft, 2.50m. Wing span 32.9ft, 10.00m. Constant chord 4.1ft, 1.50m. Dihedral 10degs. Tailplane span 8.2 ft, 2.50 m. Fin height 3.9ft, 1.20m. Total wing area 161 sq.ft, 15.0 sq.m. Total spoiler area 8.6 sq.ft, 0.80 sq.m. Fin area 12.9 sq.ft, 1.20 sq.m. Rudder area 6.5 sq.ft, 0.60 sq.m. Total elevator area 25,8 sq.ft, 2.40sq.m. Wing aspect ratio 6.6/1. Wheel track 4.9 ft, 1. 50 m. Wheelbase 4.7 ft, 1.40m. Nosewheel diameter overall 13 inch, 33 cm. Main wheels diameter overall 16 inch, 40 cm. Empty weight 2321b, 105kg. Max take off weight 5521b, 250kg. Payload 3201b, 145 kg. Max wing loading 3.40 lb/sq.ft, 16.7 kg/sq.m. Max power loading 23.01b/hp, 10.4kg/hp. Load factors design; +4.5, 2.5 ultimate. Max level speed 56 mph, 90 kph. Never exceed speed 75 mph, 120 kph. Max cruising speed 50 mph, 80 kph. Economic cruising speed 44 mph, 70 kph. Stalling speed 24 mph, 40 kph. Max climb rate at sea level 300 ft/min, 1.5 m/s. Min sink rate 325 ft/min at 31 mph, 1.6 m/s at 50 kph. Best glide ratio with power off 14/1 at 34 mph, 55 kph. Take off distance 165 ft, 50 m. Land¬ing distance 250 ft, 75 m. Service ceiling 10,000 ft, 3050 m Range at average cruising speed 622 mile, 1000 km.
Engine: JPX PUL425, 26 hp. Fuel capacity 6.6 US gal, 5.5 Imp gal, 25.0 litre. Length overall 19.8 ft, 6.00 m. Height overall 8.2ft, 2.50m. Wing span 32.9ft, 10.00m. Constant chord 4.1ft, 1.50m. Dihedral 10 degs. Tailplane span 8.2 ft, 2.50 m. Fin height 3.9ft, 1.20m. Total wing area 161 sq.ft, 15.0 sq.m. Total spoiler area 8.6 sq.ft, 0.80 sq.m. Fin area 12.9 sq.ft, 1.20 sq.m. Rudder area 6.5 sq.ft, 0.60 sq.m. Total elevator area 25,8 sq.ft, 2.40sq.m. Wing aspect ratio 6.6/1. Wheel track 4.9 ft, 1. 50 m. Wheelbase 4.7 ft, 1.40m. Nosewheel diameter overall 13 inch, 33 cm. Main wheels diameter overall 16 inch, 40 cm. Load factors design; +4.5, 2.5 ultimate. Never exceed speed 75 mph, 120 kph.
The prototype Libellule Dragonfly in translation made its first flight in May 1981, and on the 14 July (a national holiday in France), Bernard Broc flew from Paris to Avignon in almost 7 h, covering the 435 mile (700 km). This first Libellule was a two axis machine using a Pterodactyl Fledgling wing and with a monobloc all flying horizontal tail surface, yaw control being by the use of tip rudders. This horizontal tail surface was joined to the fuselage by a tapered circular section polyester boom which reduced from 8 to 5 inch (20 to 13 cm). The fuselage formed an open cockpit with a large integral windshield, also of polyester. The landing gear was tricycle with a steerable nosewheel, main wheel suspension using glass fibre laminate. In this form and assisted in its manufacture by Frangois Goethals and Bernard d’Otreppe, the Libellule was put on sale in a small way through Aviasud. Bernard Broc’s Libellule Mkl went out of production at the end of 1982.
In 1951 John Britten and Desmond Norman designed and built and flew an ultra-light monoplane, their first aircraft, which made its first flight at Bembridge, Isle of Wight, on 16 May 1951. This machine crashed on an early flight, when the petrol supply to the 40 hp Aeronca JAP J-99 twin cylinder air-cooled engine faded out. Modifications were made to the tail unit by adding smll ancillary fins to improve the directional stability, inset ailerons were fitted, the JAP engine was replaced by a 55-hp Lycoming horizontally-opposed twin and the undercarriage was replaced with braced arrangement with rubber bungee springing. It was first flown in this form in May 1951 and was withdrawn from use in 1953. It was then on exhibition in the Solent Sky Museum, Southampton, England, on loan from Michael Short of Austin Texas, USA. The general arrangement of the BN-1 is similar to that of the Comper Swift in particular G-ABUS, an aircraft that Desmond Norman was associated with along with fellow de Havilland Technical School apprentice, Tony Cole, that they jointly acquired in 1948 and restored to flying condition.
Engine: 1 × Lycoming flat-four, 55 hp (41 kW) Propeller: two-bladed fixed-pitch Length: 16 ft 7 in (5.06 m) Wingspan: 23 ft 0 in (7.01 m) Height: 10 ft 5 in (3.18 m) Gross weight: 630 lb (286 kg) Maximum speed: 84 mph (135 km/h) Cruise speed: 75 mph (120 km/h) Crew: 1
