Fabbrica Automobili e Velocipedi Edoardo Bianchi e C. Soc. An.- Milan, Italy 1916
Settled in Milan in 1900, the Milanese Company of cars Isotta Fraschini around 1910 started manufacturing engines for aeroplanes and dirigibles. In January 1915 Isotta Fraschini was requested by the Military Navy to study an engine fit to gliders. The Milanese house derived from the previous V3, a 4 in line cylinder with 110 HP power, the V4, mainly installed on Forlanini dirigibles. The V4 model, which remained as a prototype only, was succeeded by V4 A and V4 B versions. F the V4 A never passed over a pre-series production, the V4 B model was very appreciated due to its simple features, its light weight and stoutness. Some specimens was still in service up to 1928.