Pentecost Hoppicopter Model 101 / 102 / 103 / 104
Model 101, 1946
A second version of the Strap-on with a motor-cycle saddle acting as a seat and a tubular tripod assembly with three wheels as landing gear , and also a hanging stick to control the aircraft was tested later.
Model 102, 1947
Tests of the Model 101 revealed the need for several improvements, so that the 102, while somewhat resembling its predecessor, had a more powerful engine. Besides a directly engaging clutch, there was also a freewheeling device for auto-rotation in case of engine failure.
The two rotors, set at a distance of 2 feet (61 centimetres) from each other, consisted of a 4-foot (1.32-metre) tubular metal section centred at the hub; to these tubular sections the two spruce blades were attached.
The controls included collective, cyclic and differential pitch, the latter being obtained by rotating the stick handle which made the helicopter turn on its vertical axis.
Model 103, 1947
This model was similar to the previous ones, except that the rotor diameter was slightly increased and the distance between the two rotors somewhat greater.
Model 104, 1948
Once again this was an ultra-light single-seater helicopter with two co-axial contra-rotating two-bladed rotors of the same lineage as the firm's previous products. Model 104 was sent to the United Kingdom, where it remained, to be tested for the British Ministry of Supply under the aegis of a British company, Hoppicopter Ltd.
Hoppicopter Model 103
Rotor diameter: 5.18m
Weight fully loaded: 90kg
Empty weight: 40kg