The first was built in 1927 and made its first flight in 1929. Nicolas Florine built a helicopter with two rotors in tandem, turning in the same direction. To balance the reaction torques, he used his principle of inclining the axes of rotation of the rotors with respect to each other. After the implementation of scale models, one of which weighed 36 kg and left the ground several times, he built a first device (the "Type I") able to carry a pilot, propelled by a
Hispano-Suiza water-cooled engine of 180 CV. In 1930 it was partially destroyed during a static trial following a failure in its mechanical transmission. The pioneer gave the following description: In 1931 a second, lighter, design was built, and baptized "Type II". This was largely built at
Sociéte Anonyme Avions et Moteurs Renard. It was equipped with an
air-cooled 240-hp Renard engine with a vertical axis. Like its predecessor, the Type II was equipped with two tandem rotors (one at the front and one at the rear) rotating in the same direction. In order to balance the reaction torques, the axes of rotation of the rotors were inclined about 7° on either side of the longitudinal axis of the fuselage, laterally (one to the left and the other to the right). Its chassis, made of welded steel tubes, gave it a total working weight of 950 kg, i.e. 60% of the weight of the Type I wooden fuselage. The aircraft was equipped with magnesium alloy 'elephant legs' as landing gear. This model made many test flights, and eventually set an unofficial record flight duration of 9 minutes and 58 seconds. The flights began on April 12, 1933, and on October 25 of the same year, near the beech forest of Soignes, the aircraft piloted by Mr. Robert Collin, engineer at the Belgian Aeronautics Technical Service, officially beat the record for time in the air of 9 min 58 s. A few months later, in 1934, when tested in
Haren the team tried to beat the record of altitude of 18 meters realized in Rome by the machine designed by
Ascanio. During the attempt, there was a malfunction of one of the clutches of the transmission, which unbalanced the device which turned and crashed. Robert Collin, very well protected, got away without a scratch. The Florine II made more than thirty test flights between April 1933 and May 1934. A third model was then built, this time with a twin-engine configuration. The fuselage was lighter while the two
Salmson 60 hp engines were placed at the front on either side of the fuselage. The blades of the rotors were folded when stationary. The first flight was made by Collin on 15 September 1936 and tests were carried out until the autumn of 1937. However, the results were disappointing, especially in comparison with the prototype Florine II. In 1937, further development stopped. This helicopter was destroyed during World War II. ==Later years==