Fiat Aviazione, the aircraft division of the legendary Fiat automobile company, was established in 1908 in Turin and was responsible for some of the Italian aircraft industry’s most famous aircraft from the early interwar period to the late 1960s when it left the airframe manufacturing busines to concentrate on aero engines. Since 2013, though a series of mergers, acquisitions and rebrandings dating to the late 1960s, the legacy of Fiat Aviazione has lived on through in Avio S.p.A., a Turin based subsidiary of General Electric’s aviation arm.
The G.91 was part of a series of aircraft designed by the masterful Giuseppe Gabrielli (1903-1987) during his tenure with the company which lasted from 1931 to the end of their airframe design activities in the late 1960s. In the catalogue of Fiat aircraft, Gabrielli designed machines are easily recognised by the “G” prefix; this was in keeping with Fiat’s practice of using the designer’s initials as the prefix for the aircraft model number.
While the G.91 was designed to be a strightforward and simple aircraft, the story of it’s development and introduction to service is anything but. At that, Let’s spend some time with the Fiat G.91, or “Gina” as it was nicknamed by many who worked with it:
Defining the Light Fighter
Very early in the jet age, with the reality of nuclear conflict looming large in the background of rapidly increasing Cold War tensions, the nations of NATO were forced to reevaluate the shape and nature of how their air combat assets were deployed and maintained in continental Europe.
The Korean War had highlighted the need for greater air support of ground forces in modern combat and revealed some of the drawbacks of the increasingly complex nature of jet combat aircraft. One of the main drawbacks was that with increasing complexity came rising costs that sharply curtailed the number of aircraft that could be ordered to the point that they could not be purchased in high enough numbers to be deployed in battle effectively. Air bases were getting bigger to accomodate more complex aircraft support facilities, runways longer to support heavier aircraft and the distance between the air base and the front lines was increasing to the point where the aircraft would have very little time over their targets before having to return to base for fuel. Additionally, the larger size of fixed air bases made them very easy targets and impossible to conceal.
Consideration of those factors led NATO to issue a requirement in 1953 for a new light weight strike aircraft that could be deployed away from large bases and with minimal support facilities. The aircraft would also be able to be produced in large numbers cheaply and be seen as an expendable asset that could be used widely in NATO.
The specification for the new aircraft stipulated that it had to be operable from grass and straight stretches of road, take off in 1,100 metres, have a combat range of 280 kilometres that included 10 minutes time over a target, carry a fixed armament of four 12.7mm machine guns or two 20mm cannons in addition to 454 kg of unguided munitions under the wings, have a maximum speed of Mach 0.95 and a maximum empty weight of no more than 2,268 kg.
It was a high order for the time period and the state of jet combat aircraft technology of the time. However, thanks to work already done in Great Britain in the very early 1950s, it was not an impossible goal to attain. By 1952, work on what would become the Folland Gnat trainer was well underway and work on the Bristol Orpheus engine that would power it had begun in 1953. By late 1954, the Orpheus engine had been run for the first time.
The Orpheus would solve one of the biggest obstacles to the light fighter concept at the time, finding an engine which could deliver the required thrust and yet be light enough to keep the aircraft within the stipulated weight parameters. The Orpheus, like the aircraft it was designed to power, was of simple design and easy to service without specialised equipment.
Selection and Development
By July of 1955, after nearly two years of selection, NATO announced their shortlist of the winning designs which would be approved for prototype development and final competition for the new light fighter. Fiat’s competition came in the form of the Dassault Étendard VI and Breguet Br.1001 Taon, both from France. Aside of the original specifications, NATO had also dictated that all three competing aircraft were to use the Orpheus engine as a power source.
The selection of the Orpheus was due in large part to America heavily funding the engine’s development through the US Mutual Weapons Development Programme. In fact, though British by design, relatively little British money funded the development of the engine.
The G.91 first flew in August of 1956, nearly a full calendar year before the first flight of either French design going against it. Despite this headstart, the initial G.91 prototype experienced some control and vibration problems and was lost in a crash in early 1957. After extensive investigation and reworking, a revised second prototype flew for the first time in July of 1957.
Third and fourth G.91 prototypes were sent to France, where the competition was being held in Autumn of 1957, and performed very well. NATO anounced the G.91 to be the winner of the competition in January of 1958.
While the G.91 had been successful in the competition for NATO’s new light fighter, political and financial factors as well as fading interest in the light fighter concept would conspire against it becoming a widely used aircraft. Initial users of the G.91 were to be France, Italy, Turkey and West Germany. America would provide partial funding for the French, German and Italian G.91 purchases and fully fund the Turkish order.
France, using the loss of the first G.91 prototype as an arguing point, disputed the outcome of the competition and opted to further develop the Dassault Étendard on their own rather than have anything to do with the Italian aircraft.
In 1961, evaluation samples of the G.91 were provided to Greece and Turkey as well as the U.S. Army and U.S. Air Force. In the end, none of them accepted the aircraft into service. After evaluation, Turkey cancelled their G.91 order and the aircraft that had already been built for them by that point were given to West Germany instead.
Interest in the G.91 was shown by Austria, Israel, Norway, South Africa and Switzerland. However orders from the European nations never materialized and the Italian government vetoed sales to Israel and South Africa for political reasons.
Ultimately, all Ginas built served only Italy, Portugal and West Germany.
The G.91 in Production and Service
The G.91 enjoyed a 19 year production run and assembly lines existed for it in both Italy and West Germany. While production totals vary somewhat by source, most place the number of Ginas built between 750 and 770.
The G.91 had given NATO nearly 40 years of service when the last ones were retired from Italian service in 1995.
West Germany was the first G.91 user to retire their fleet of the aircraft, doing so in the early 1980s. Over the years, many former German Ginas and spare parts for them were purchased by Portugal. It was in Portuguese service that the G.91 would see combat; several of the aircraft were sent to Africa for close air support of ground troops in the Portuguese Colonial War which lasted from 1961 to 1974. Portugal continued to use the G.91 until 1993.
Five main operational variants of the G.91 were produced:
The R/1 was the first production version of the G.91 and differed outwardly from pre-production machines by having a redesigned nose capable of holding cameras for reconnaissance work. Changes to avionics and instruments created the R/1A subvariant while structural strengthening created the R/1B.
This was a variation for the Luftwaffe which was equiped with a pair of 30mm cannons as fixed armament.
Initially intended for Greece and Turkey, the R/4 fleet was transfered to the Luftwaffe and used for training until retirement in 1966. Several of this variant were sold to Portugal after their Luftwaffe days were over.
This was the two seat training variant used by the Italian air force.
The T/3 was the Luftwaffe training variant. Several found their way into Portuguese service.
I have not included the later two engine G.91Y in the above list as it is only a G.91 in the most nominal of senses. Beyond a passing resemblance and a designation that suggests it being a member of the G.91 family, the G.91Y was a completely different aircraft nose to tail that didn’t have a single component in common with the single engine G.91 line.
The Gina Today and Further Reading
Many examples of the G.91 survive in museums across Europe and further afield, so getting a close look at one today is not an overly difficult task depending on your geographic location.
As of late 2021, it would appear there are no flying examples of the G.91. However, there is a long term project in Germany to restore a T/3 to flying status. While the group restoring the aircraft does not seem to have a dedicated website, you can see their progress on their “34+39 Back to the Sky” page on Facebook.
The aircraft is in a good state and the team seems optimistic. Hopefully, we will see a G.91 grace the skies again someday.