Isotta-Fraschini Asso 750
On loan from the Chicago Museum of Science & Industry
To celebrate the tenth anniversary of the Italian Air Force, General Italo Balbo led a squadron of 25 Savoia Marchetti S.55X's on a famous 12,305 mile round-trip from Italy to the 1933 Chicago World's Fair. At the time, it was the longest large-formation flight in history.
Picked because of their superior reliability, two Asso 750 engines powered each of these planes and not one failed in over 2,000 hours of accumulated flying time. This unusual engine, with its three banks of six water-cooled cylinders, could produce 820 hp at 1,700 rpm. Two of its advanced features were its fully enclosed valve push rods and the corrugated water jackets designed to compensate for the differential expansion between the hot cylinders and cold water jackets.
This engine is located in the Civilian Hangar near the right wing of the Sikorsky S-39B.