Fiat G.50 - Design and Development

Design and Development

The Fiat G.50 was designed by Giuseppe Gabrielli, who started designing a single-engined monoplane fighter in April 1935. Work began on two prototypes in mid-summer 1936, with construction was entrusted to the workshops of the CMASA (Costruzioni Meccaniche Aeronautiche S.A.) subsidiary of Fiat at Marina di Pisa. Comandante Giovanni de Briganti, chief test pilot of the G.50 program, flew the first prototype on 26 February 1937 from Caselle airfield, Turin, reaching a top speed of 472 kilometres per hour (255 kn; 293 mph) and climbing to 6,000 metres (19,700 ft) meters in 6 minutes, 40 seconds.

The G.50 was a low-wing monoplane of all-metal construction, with a semi-monocoque fuselage with light alloy skinning, while the wings had a steel tube centre-section structure with duralumin outer wings and alloy skins. Flaps were fitted to the aircraft's wings to improve take-off and landing performance. Powerplant was a single Fiat A.74 R.C.38 14-cylinder air-cooled radial engine, rated at 870 hp (650 kW) for take-off and 960 hp (720 kW) at 3,000 m (9,800 ft) enclosed in a NACA cowling and driving a three-bladed constant speed propeller. The pilot sat in an enclosed cockpit under a sliding transparent canopy. He was provided with a reflector sight to aim the fighter's armament of two 12.7 mm (.5 in) Breda-SAFAT machine guns with 150 rounds of ammunition per gun fitted ahead of the cockpit, syncronised to fire through the propeller. It was fitted with a retractable tailwheel undercarriage, with the mainwheels retracting inwards and a castoring tailwheel. It was the first front line Italian monoplane fighter with a retractable undercarriage, an enclosed cockpit and a constant speed propeller; these improvements gave it a maximum speed that was 33 km/h (21 mph) faster than its contemporary, the Fiat CR.42 biplane.

In 1937, along with the first pre-series machines, a gruppo sperimentale (experimental group) was formed. The first versions could have different weaponry: one or two 12.7-mm (.5 in) Breda-SAFAT machine guns on the nose and two more 7.7-mm (.303 in) Breda-SAFAT in the wings. Later versions were distinguished by a larger rudder.

In September 1937, Fiat received a first order for 45 aircraft. Before placing a larger order, the Air Ministry held a comparative test with the new Macchi MC.200. On 20 October 1937, de Briganti was killed on the sixth evaluation flight of the second prototype (M.M.335), when the aircraft failed to pull out of a high-speed dive. Flight tests at Guidonia showed that the aircraft went too readily into an uncontrolled spin, a highly dangerous trait, especially at low level where recovery was impossible.

During a visit by Italian King Victor Emmanuel III and Prime Minister Benito Mussolini, another tragedy occurred at Guidonia. While performing a low, fast pass, three G.50s flown by experienced pilots, Maggiore (Squadron Leader) Mario Bonzano and Lieutenants Beretta and Marasco, got into difficulty. Beretta's aircraft spun uncontrollably and crashed into the ammunition laboratory, killing the pilot. Despite the crashes, flight tests were satisfactory and the Freccia proved to be more maneuverable than the faster Macchi MC.200, which was declared the winner of the Caccia I ("Fighter One") competition on 9 June 1938. On account of its maneuverability, the Regia Aeronautica Commission decided to order the G.50 as well, rejecting the third contender, the IMAM Ro.51.

The first aircraft were delivered to the Regia Aeronautica in early 1938. Italian pilots did not like the enclosed canopy because it could not be opened quickly and, being constructed from plexiglass of very poor quality, was prone to cracking or abrasion by sand or dust, limiting visibility. In addition, exhaust fumes tended to accumulate in the cockpit, so pilots usually flew with the canopy locked open. Consequently,an open cockpit was installed in the second batch of 200 machines. After 1939, the main production was shifted to the CMASA factory in Marina di Pisa, Tuscany.

In 1938, the Regia Aeronautica requested a two-seater trainer which was designated the G.50/B (Bicomando – dual control). The first were built in the second half of 1939. The student pilot sat in the front in a closed cockpit with two roll bars. The first five aircraft were part of the 1a serie ("first series"). Further production was entrusted to CMASA, who completed 106 G.50/Bs. A G.50/B was later transformed into a reconnaissance aircraft equipped with a planimetric camera. Another G.50/B was adapted with a hook to operate as a naval reconnaissance aircraft from aircraft carrier Aquila, but the ship was never completed. In September 1940 a slightly improved version appeared, the G.50 bis. Its main advantage was the extended combat range provided by an additional tank of 104 litres (27 USgal), increasing range from 645 km to 1,000 km.

The last version was the G.50/V (Veloce – fast) built in mid-1941 by CMASA and equipped with a DB.601 engine of 1,075 CV. During tests at Fiat Aviazione's airfield in Turin, it reached a top speed of 570 km/h in level flight and climbed to 6,000 meters in 5 minutes 30 seconds. By this time, however, Gabrielli had already designed the Fiat G.55, and Fiat had obtained the licence to build the 1,475 CV Daimler Benz 605, so the G.50/V was used to test new equipment and was then scrapped.

Total G.50 production was 784 aircraft, 426 built by Fiat Aviazione and 358 coming from CMASA. There were 58 exports: 13 to Spain, 35 to Finland and 10 to Croatia.