Bloch MB.90
| Industry | Aviation |
|---|---|
| Founded | 1932 |
| Headquarters | France |
| Products | Light aircraft |
The Bloch MB.90 holds the distinction of being France's inaugural all-metal light aircraft. Only two units were ever built, with their maiden flights occurring in 1932, followed by the creation of several derivative models.
Design and development
Despite lacking commercial success, the MB.90 and its derivatives were significant as the first French light aircraft constructed entirely from metal. This single-engine aircraft featured a braced high wing configuration, with its wing comprising two sections built around duralumin spars and covered in fabric. The fuselage was rectangular in shape, constructed from a tubular steel framework sheathed mostly in fabric, except for the plywood flooring and cabin side panels. Seating arrangements are inconsistently reported: early sources mention side-by-side seating, whereas later analyses indicate a tandem layout. The wings were supported by parallel struts connecting to the lower longerons of the fuselage. The tail assembly included a conventional rectangular horizontal stabilizer and a triangular vertical fin equipped with an unbalanced rudder.
Originally designed to be powered by a Renault engine, the MB.90’s initial flights utilized a de Havilland Gipsy III air-cooled, four-cylinder inverted inline engine. Its fixed tailwheel landing gear incorporated V-shaped split axles hinged to the lower fuselage longerons, complemented by shock-absorbing struts attached to the wing bracing.
At the 1932 Paris Aero Show, two variants equipped with Renault 4Pei inline engines were presented: the MB.91 and MB.92. The MB.91 was incomplete and never took flight but introduced design elements such as diverging wing struts, a rounded vertical fin, and streamlined split-axles that were later adopted on subsequent models. While the MB.91 maintained side-by-side seating, the MB.92 featured tandem seating within a slimmer fuselage profile. Later on, an option to install a Pobjoy Niagara engine was made available for the MB.91. One of the original MB.90s was converted into the MB.93, incorporating similar fin and landing gear modifications and powered by a de Havilland Gipsy Major I engine.
In 1933, Bloch expanded its lineup with the MB.100, a four-seat aircraft driven by a Hispano-Suiza 5Q five-cylinder radial engine (a licensed version of the Wright R-540 Whirlwind). The MB.100 accommodated two rows of side-by-side seats, marking Bloch’s entry into larger light aircraft segments.
Operational history
Both MB.90 aircraft were registered to participate in the third FAI International Tourist Plane Contest, Le Challenge de Tourisme International, held in Germany in August 1932, listed as equipped with Renault engines; however, they failed to meet the registration deadline and thus did not compete. The MB.92 remained officially registered in France at least until 1937.
Variants
- MB.90
- First flown in June 1932 powered by a de Havilland Gipsy III engine; subsequently fitted with a Renault 4Pei inverted inline engine for display at the 1932 Paris Aero Show. Characterized by parallel lift struts and a triangular vertical fin.
- MB.91
- Never flown; exhibited without wings at the 1932 Salon featuring the Renault engine. Distinguished by wing struts converging toward the fuselage, a rounded fin, and faired-in axles. A Pobjoy Niagara powerplant was proposed in 1933.
- MB.92 Grande Tourisme
- Took flight on 9 September 1932 utilizing the Renault engine paired with a metal propeller. It had a rounded fin, similar struts, and faired landing gear akin to those on the MB.91. Displayed at the 1932 Salon as a narrower fuselage model with tandem seating.
- MB.93
- A conversion of an existing MB.90 fitted with a de Havilland Gipsy Major I engine and adopting fin, strut, and undercarriage features from the MB.91.
- MB.100
- A four-seat evolution derived from the MB.90 platform.