Macchi M.C.72

https://en.wikipedia.org/wiki/Macchi_M.C.72

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 speed
record for piston engine-powered seaplanes which still stands.

The Macchi M.C. 72 was one of a series of seaplanes developed by Macchi
Aeronautica. An earlier model, the M.24 was a twin-engine flying boat armed with
machine guns and capable of carrying a torpedo. Later in the 1920s, Macchi
focused on speed and on winning the Schneider Trophy. In 1922, the company hired
aircraft designer Mario Castoldi to design high-speed aircraft.

In 1926, the company won the trophy with the M.39 which attained a top speed of
396 km/h (246 mph). Further aircraft, the M.52, M.52R and the M.67, were
designed and built but victory in the Schneider races kept eluding the Italians.
Castoldi then designed the ultimate racing seaplane, the M.C. 72, a
single-seater aircraft with two floats.

The M.C. 72 design was unique with a fuselage partly metal to the cockpit and
wood monocoque bolted to the front tubular portion by four bolts. The
streamlined nose contours enclosed an oil tank with its outside wall exposed to
the airstream. The wing was all metal with flat tubular water radiators smoothly
faired into the wings. The twin pontoons had three smoothly-faired radiators on
the outer surfaces, the forward radiator for water and the centre and rear
radiators for oil cooling. The float struts also featured water radiators and
another radiator was fitted during hot conditions under the fuselage running
from cockpit to tail.

The M.C. 72 was built in 1931 with the idea of competing for what turned out to
be the final Schneider Trophy race, but due to engine problems, the M.C. 72 was
unable to compete.

Instead of halting development, Macchi continued work on the M.C. 72. Benito
Mussolini personally took an interest in seeing development of the M.C. 72
continue and directed state funds to the company

Role
Seaplane racing aircraft

Manufacturer
Aeronautica Macchi

Designer
Mario Castoldi

First flight
July 1931

Retired
23 October 1934 (last flight)

Primary user
Kingdom of Italy

Number built
5

For two years, the M.C. 72 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
contra-rotating propellers powered by a modified FIAT AS.6 supercharged V24
engine generating some 1,900-2,300 kW (2,500-3,100 hp).

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 (423.5
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 (434.7 mph) with the M.C. 72. This feat was in
fact achieved on 23 October 1934, when Agello piloted the M.C. 72 for an average
speed of 709.2 km/h (440.7 mph) over three passes. This record remains (as of
2016) the fastest speed ever attained by a piston-engine seaplane. After this
success, the M.C.72 was never flown again.

Speed record

The M.C. 72 held the world speed record for all aircraft for five years. For
comparison, the record holder for a land-based aircraft was held (for a time) by
the Hughes H-1 Racer with a top speed of only 566 km/h (352 mph). Then in 1939,
two German racing aircraft passed the M.C. 72. The first was a Heinkel prototype
fighter which reached the speed of 746 km/h (463 mph). The second was the
Messerschmitt Me 209, built by Messerschmitt solely for the purpose of setting a
new world speed record, which it achieved at 756 km/h (469 mph) on April 26 –
less than 5 months before the start of World War II. The current world speed
record for a piston-engine aircraft is 528.33 mph (850.26 km/h) set by a heavily
modified Grumman F8F Bearcat named Rare Bear over three km in 1989. However, the
M.C. 72 record still stands today as the world's fastest propeller-driven
seaplane.


Specifications (M.C.72)

General characteristics
Crew: 1
Length: 8.32 m (27 ft 4 in)
Wingspan: 9.48 m (31 ft 1 in)
Width: 3.3 m (10 ft 10 in)
Wing area: 15 m2 (160 sq ft)
Airfoil: Biconvex
Empty weight: 2,505 kg (5,523 lb)
Gross weight: 2,907 kg (6,409 lb)
Max takeoff weight: 3,031 kg (6,682 lb)
Powerplant: 1 × Fiat AS.6 24-cylinder coupled V-12 liquid-cooled piston engine
Propellers: 4-bladed contra-rotating fixed-pitch propeller

Performance
Maximum speed: 709.209 km/h (441 mph; 383 kn) (world speed record)



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