you know the name Jacuzzi, because of the hot tub. But the Jacuzzi brothers went into business first by making airplane propellers in Berkeley California, after WW1 they designed their own airplanes, including the Jacuzzi J-7

This propeller was manufactured by the Jacuzzi brothers around 1918.

 It was designed for use on aircraft powered by Liberty V-12 aircraft engines, primarily American-built DH-4s. 

The Jacuzzi brothers, Giocondo (1895–1921), Frank (1889–1973), Rachele (1886–1937), Candido (1903–86), Joseph (1891–1965), Gelindo (1894–1950), and Valeriano (1887–1973) originally opened a machining company in Berkeley, California, in 1915. 

After seeing propellers on aircraft flying at the 1915 Panama-Pacific International Exposition in San Francisco, Rachele was inspired to design a better one. 

Impressed by his new aerodynamic propeller design, the US government awarded the Jacuzzi brothers a contract to manufacture their propellers for World War I military aircraft. After the war, the brothers expanded their aviation business and even designed their own airplanes, including the Jacuzzi J-7.

 In 1921, they left the aviation industry and decades later, their company produced whirlpool hot tubs for which their name is most recognized today.

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