Giovanni Sacchi was a celebrated model maker who worked in Milan with leading designers and architects through the latter part of the Twentieth Century. He is credited with interpreting many of the most iconic examples of Italian design of the period. Models by Sacchi have featured in many international expositions including Tsukuba ' Expo, Japan, in 1985, Expo’ 88 in Brisbane and in Seville in 1992, as well as editions of Exempla in Monaco of Bavaria in 1980 and 1992 and as exhibits in Paris, Stuttgart, Nagoya and Aspen in the United States during 1989. Monographic exhibitions dedicated to his models were also presented at both the 1983 and 2000 Milan Triennials.

As one of the 37 national participants in the 1988 World Expo themed on Leisure in the Age of Technology staged in Brisbane the Italian Pavilion included examples of modern design in luxury cars and motorcycles as well as Sacchi’s models of extraordinary, historically innovative ideas in the form of various prescient inventions by the renowned epitome of a “Renaissance Man”, Leonardo Da Vinci, 1452 -1515. This model of Da Vinci’s “helical aerial screw” was presented during the World Expo to Griffith University through its School of Languages by the Commissioner General of the Italian Pavilion at Expo 88, the Hon. Luigi Turchi.

Painter, sculptor, anatomist, musician, geometer, civil engineer and inventor, Da Vinci had a profound fascination with flight recording an extraordinary study of the physiology of birds and the mechanics of their aerodynamics in a codex of c. 1505. Prior to this he had already engaged with the problem of human flight and explored the possibility of creating an ornithopter (a machine capable of flight by emulating flapping wings) as early as 1485. Although rumoured to have been unsuccessfully tested, there is no substantive proof that Da Vinci’s models were ever realised.

This Flying Machine modelled by Sacchi for the 1988 display recreates a famous sketch from Leonardo’s diaries of c. 1493 proposing a helical air-screw vehicle that would ascend by four men powering the revolving sail on a platform mobilised by reduced friction through the use of ball bearings, itself an entirely original proposition. The device pis widely credited as the precursor to the Helicopter although its design suggests only an interest in vertical motion rather than directional flight and, in its own terms, was never sufficiently powered or mechanically a viable working proposition.