The Macchi M.C. 72 was an experimental seaplane designed and built by the Italian aircraft company Macchi Aeronautica. The M.C. 72 held the world speed record for all aircraft for five years. In 1933 and 1934, it set a world record for speed over water which still stands to this day.
For two years, the plane suffered from many mechanical defects, as well as the loss of two test pilots who died trying to coax world class speed out of the M.C. 72 (first Monti and then Bellini). The final design of M.C. 72 used double, contra-rotating propellers powered by a modified FIAT AS-6 engine V24 engine) generating some 1,900-2,300 kW (2,500-3,100 hp) (thanks to supercharging).
After 35 flights, the engines were overhauled in preparation for a record attempt. The aircraft finally lived up to expectations when it set a new world speed record (over water) on 10 April 1933, with a speed of 682 km/h (424 mph). It was piloted by Warrant Officer Francesco Agello (the last qualified test pilot). Not satisfied, development continued as the aircraft's designers thought they could break 700 km/h (430 mph) with the M.C. 72. This feat was in fact achieved on 23 October 1934, when Agello piloted the plane for an average speed of 709 km/h (440 mph) over three passes. This record remains (as of 2010) the fastest speed ever attained by a piston-engine seaplane. After this success, the M.C.72 was never flown again.