During early 1938, the Freccias served in the Regia Aeronautica (the Italian Air Force) and with its expeditionary arm, the Aviazione Legionaria, in Spain, where they compared well in speed and manoeuvrability with their adversaries in the theatre.

[2] External to Gabrielli's influence, the fighter's design was also shaped by the issuing of a specification during 1936 which sought a modern interceptor aircraft for the Regia Aeronautica (the Italian Air Force).

In advance of the placement of a larger order, the Italian Air Ministry decided to hold a round of comparative 'fly-off' test flight between the type and the newly developed Macchi MC.200.

[12] Flight tests conducted 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.

While performing a low, fast pass, three G.50s flown by experienced pilots, Maggiore (Squadron Leader) Mario Bonzano and Lieutenants[clarification needed] Beretta and Marasco, got into difficulty.

[13] Despite the crashes, overall results from the flight test programme were deemed to be satisfactory and the Freccia proved to be more manoeuvrable than the faster Macchi MC.200, and the G.50 was declared the winner of the Caccia I ("Fighter One") competition on 9 June 1938.

Reportedly, Italian pilots did not like the enclosed canopy because it could not be opened quickly and, being constructed from plexiglas of relatively poor quality, was prone to cracking or abrasion by sand or dust, limiting visibility.

During tests at Fiat Aviazione's airfield in Turin, it reached a top speed of 570 km/h (350 mph) in level flight and climbed to 6,000 m (20,000 ft) in five minutes 30 seconds.

On 8 March, a Hungarian volunteer pilot, 2nd lieutenant Wilmos Belassy, apparently dived into the Baltic sea, after running out of fuel and failing to cross it from Sweden to Finland.

However, by the time of the outbreak of the Second World War, rapid advancements in the field of aviation had contributed to the type being considered to be both underpowered and underarmed in comparison to competing frontline fighters then in use by the main powers.

[25] Upon Italy's entry into the Second World War in June 1940, the Regia Aeronautica possessed a total of 118 G.50s that were available for operations; of these, 97 aircraft were available to perform front line duties while others were either in maintenance or awaiting delivery.

[30] Those G.50s that were deployed were early models and thus furnished with an open canopy, which was useful in a typical Mediterranean climate but led to the pilots suffer heavily in the colder weather of northern Europe.

On 9 January 1941, these fighters performed their first combat mission in the theatre when Capitano Pilota (Flight Lieutenant) Tullio De Prato, commander of 150ª Squadriglia, was attacked by a Hawker Hurricane Mk I on the front line, forcing him to crash-land in the desert.

Tactical surprise was often a decisive factor in a given engagement, as shown on 14 April when a formation of 66 Axis aircraft, including eight G.50s from 351ª Squadriglia, attacked British forces stationed in the vicinity of Tobruk.

73 Squadron were outnumbered in this engagement, resulting in the Hurricanes, which were only marginally faster than the G.50, having to ignore the Axis fighters and concentrate their efforts upon attacking incoming bombers, which posed the greatest threat.

[citation needed] This new version had almost two hours of flight endurance, due to the addition of an extra fuel tank in the internal fuselage section (which had been originally configured as a bomb bay).

For instance, on the evening of 9 July 1941, Sergente Maggiore Aldo Buvoli of 378ª Squadriglia, 155° Gruppo Autonomo, took off from Castel Benito airfield to patrol Tripoli harbour and intercepted a flight of seven Blenheim light bombers, which had been engaged in a low-level attack on the ships.

On 19 November 20° Gruppo, based at Sid el Rezegh, suffered heavy losses when British armoured forces suddenly attacked the airfield.

Mario Bonzano, now a Tenente Colonnello and commander of 20° Gruppo, was among the captured, and his deputy, Furio Niclot Doglio, was almost shot down, since he was unaware of the British operation.

[43] During the Greek campaign, adverse weather conditions was often responsible for hampering Axis air operations, however, a number of fiercely-fought aerial engagements were fought on several days, often accompanied by a large amount of overclaiming by personnel on both sides of the conflict.

A few days earlier, a British cargo ship had delivered six Hurricanes and several Wellington bombers to Paramythia, Greece, boosting RAF power in the region.

On 28 February 1941, RAF units intercepted a formation of Italian bombers and their escorts, claiming 27 aircraft shot down and several others damaged in the ensuing battle.

[47][45] During the course of the Greek campaign, a flight of 10 G.50 fighters were recorded as having been lost, including both combat losses and others that had been destroyed by a combination of accidents and as a consequence of Allied bombing missions against Italian airfields.

[citation needed] The top-scoring Italian pilot to use the G.50 was Furio Lauri, who was credited with 11 "kills" prior to the end of 1941, eventually achieving a final score of 18 enemy aircraft downed.

On a training flight, during a dive from 3,500 m (11,500 ft), Lieutenant Tapani Harmaja reached an estimated speed of 780 km/h (480 mph), which was considered excessive for the structural integrity of the aircraft.

[52][53] Germany hindered the transit of the aircraft, so they were dismantled and embarked in La Spezia on the Norwegian ship Braga, which set sail for Turku, Finland, on 20 January.

The Soviets brought better, newer types of fighter to the front line in 1942 and 1943, while the Fiats were becoming old and run-down and the lack of spare parts meant that pilots were restricted to a minimal number of sorties.

The most successful Finnish G.50 pilots were Oiva Tuominen (23 victories), Olli Puhakka (11[60] or 13), according to other sources, Nils Trontti (6), Onni Paronen (4), Unto Nieminen (4) and Lasse Lautamäki (4).

[61][62] In October 1941, the Croatian Air Force Legion requested military aid from Italy, that country agreed to deliver 10 Fiat G.50s (nine single-seaters and one two-seater), along with ancillary equipment.

[66] After the Italian armistice of 8 September 1943, the Luftwaffe supplied the Croatian Air Force Legion with 20–25 Fiat G.50s captured on Regia Aeronautica airfields in the Balkans.