Fiat G . 91 The Fiat G . 91 was an Italian jet fighter aircraft . It was the winner of the NATO competition in 1953 as standard equipment for Allied air forces . It entered in operational service with the Italian Air Force in 1961 , with the West German " Luftwaffe " , in 1962 , and later with the Portuguese Air Force . It was in production for 19 years . 756 aircraft were completed , including the prototypes and pre - production models . The assembly lines were finally closed in 1977 . The Fiat G . 91 enjoyed a long service life that extended over 35 years . It was widely used by Portugal in the Portuguese Colonial War in Africa . A twin - engined variant was known as the Fiat / Aeritalia G . 91Y . Design and development . In December 1953 , NATO Supreme Command issued specifications for a new light tactical support aircraft . European manufacturers were invited to submit their designs for this requested " Light Weight Strike Fighter " role . The G . 91 was designed to this specification by the Italian engineer Giuseppe Gabrielli , hence the " G " designation . The competition was intended to produce an aircraft that was light , small , expendable , equipped with basic weapons and avionics and capable of operating with minimal ground support . These specifications were developed for two reasons : the first was the nuclear threat to large air bases , many cheaper aircraft could be better dispersed , and the other was to counter the trend towards larger and more expensive aircraft . The technical requirements were : The challenge of providing an engine that matched the requirements of lightness and power , reliability and ease of maintenance was solved by using the Bristol Siddeley Orpheus turbojet . The designs were required within two months of the competition . The special committee had to choose from eight projects . Besides the G . 91 , these included the Northrop N - 156 , Dassault Mystère XXVI ( future Dassault Étendard IV ) , Sud - Est Baroudeur , Aerfer Sagittario II and the Breguet Taon Br . 1001 . These designs were assessed starting on 18 March 1953 by AGARD ( Advisory Group for Aeronautical Research and Development ) under the leadership of Von Karman . Project selections took 18 months to complete . The first result was announced on 30 June 1955 : the winning projects were , in order : the Breguet Br . 1001 Taon and the Fiat G . 91 . A third was added to these two aircraft : the Mystère XXVI , and three prototypes of this design were also ordered . The G . 91 first flew on 9 August 1956 at the Caselle airfield , Turin , in the hands of Chief Test Pilot Riccardo Bignamini , with a seven - month lead over the Dassault prototype and almost a year ahead of the Breguet Taon . The intensive series of tests that followed the maiden flight was not without its setbacks . The most serious problem was the elimination of aeroelastic vibrations which , on 20 February 1957 , led to the destruction of the first G . 91 prototype . The re - engineering work to cure the problem was very extensive and resulted in the second prototype being fitted with a larger tail , a 6 cm ( 2 in ) higher canopy , a ventral fin and some other modifications . This aircraft flew in July 1957 , but it was not sent to the final evaluation . The third and fourth G . 91 prototypes were sent to France , for the competition . The final selection of the competing designs was planned for late 1957 . In September 1957 , at the Centre d ' Essais en Vol at Brétigny - sur - Orge , in France , the three rival aircraft types met for evaluation trials . During the trials the Italian aircraft performed impressively and , in January 1958 , the Fiat G . 91 was officially declared the winner . Following a meeting of NATO Defence Ministers in April 1958 it was agreed that the G . 91 would be the first NATO lightweight strike fighter , it would be followed in 1961 by the Breguet Taon . A production meeting was planned for May 1958 to discuss the production of the aircraft with financial support from the United States , the Americans would provide some of the finance for the French , German and Italian aircraft and pay for the Turkish aircraft . The defence ministers reached agreement to order 50 aircraft for each country . Given the large economic and commercial interests at stake , there was a certain amount of controversy surrounding this decision . After the loss of the G . 91 prototype , the French government preferred to pursue development of the locally - designed Étendard . The British government similarly ignored the competition to concentrate on Hawker Hunter production for the same role . The Italian government also ordered the G . 91 for the Italian Air Force before the results of the competition were known . These pre - production machines would later go on to serve for many years with the Italian aerobatic team , the " Frecce Tricolori " as the G . 91 PAN . The type was also considered by Austria , Norway , Switzerland , and even the United States Army , which briefly evaluated the type as a possible Forward Air Control aircraft before relinquishing all fixed - wing aircraft operations to the Air Force . Production . Aeritalia built 174 G . 91s for Italy , plus 144 R / 3 variants for West Germany ( including 50 that had been ordered and then cancelled by Greece and Turkey ) . The German order involved a production run of 294 G . 91s built in Germany by Flugzeug - Union Süd ( a consortium of former competitors Messerschmitt , Heinkel and Dornier ) . These were the first combat aircraft built in Germany since World War II . The first order was for 50 machines from Aeritalia , then Dornier and other German firms had an order for 232 machines , later increased to 294 . The " Luftwaffe " ( German Air Force ) also bought 44 G - 91T / 3 two - seat trainers and another 22 were produced in Germany , ending production in 1972 . The " Luftwaffe " had intended to equip a further four wings with the G . 91R / 3 but initial operating experience with the type left the Luftwaffe disappointed with the aircraft ' s performance and further orders were cut . Some Luftwaffe G . 91s were emblazoned with " pig " emblems as a comment on the aircraft ' s lacklustre performance . Operational history . Italian service . The first G . 91s entered service with the Italian Air Force in August 1958 , with 103mo " Gruppo " , 5a " Aerobrigata " , called " " Caccia Tattici Leggeri " ( CTL ) " , based at Pratica di Mare Air Force Base , the same with " Reparto Sperimentale di Volo " . The next operational unit was 14mo " Gruppo " , " Seconda Aerobrigata " in 1961 . This unit had its role shifted to tactical support , because its groups were 14mo , 103mo ( dispatched from 5 A / B to this " Aerobrigade " ) and 13mo ( only in reserve ) . All of them were based at Treviso - Sant ' Angelo . The last G . 91 was phased out and retired by Italy in 1995 . German service . Forty - five G . 91 T / 3 Fiat built two - seat trainer aircraft were ordered for the " Luftwaffe " , the first 35 being allocated to " Waffenschule 50 " ( Weapon School 50 ) with the balance of the order divided between operational units . 22 aircraft were built by Dornier between 1971 and 1973 , these aircraft were used to train Weapons Systems Officer s for the F - 4 Phantom . Five Fiat built G . 91R / 3 aircraft were delivered to " Erprobungstelle 61 " for trials with subsequent deliveries being allocated to " Aufklarungsgeschwader 53 " based at Erding , near Munich along with " Waffenschule 50 " . The first Dornier - built example of this variant was flight tested on 20 July 1961 . The G . 91R / 3 equipped four newly formed " Leichten Kampfgeschwadern " ( light attack wings ) , often replacing former F - 84 Thunderstreak units . Fifty G . 91 R / 4 aircraft were taken up from a cancelled Greek / Turkish order but being unsuitable for operational use were used as training aircraft and were operated solely by " Waffenschule 50 " . When the initial training programme was completed the R4 was retired in 1966 , 40 surviving airframes were sold to Portugal . Other R / 4 aircraft remained in Germany and were transferred to ground instructional use or displayed at recruitment presentations . On 1 January 1970 , the " Luftwaffe " fleet consisted of 310 G . 91 R / 3 and 40 G . 91T aircraft , and by 1976 only 20 of the R / 3s had been lost to accidents , a loss rate of 6 % . The G . 91 R / 3 was to be replaced in the early 1980s by the Dassault / Dornier Alpha Jet which operated in the same role , with the last G . 91s being retired in 1982 . Portuguese service . From 1961 , Portugal became involved in fighting against nationalist movements in its African overseas territories , the series of conflicts becoming known as the Portuguese Colonial War . Portugal had deployed a detachment of F - 86 Sabre s to Portuguese Guinea in August 1961 , prior to the outbreak of major fighting , but was forced to withdraw the jet fighters back to Europe owing to pressure from the United States and the United Nations , who imposed an arms embargo . This left a gap in air cover for Portugal ' s African colonies , both in the close air support role , and in the air defence role . In 1965 , as the scale of fighting increased , Portugal attempted to purchase 100 surplus Canadian built Sabre Mk 6s from West Germany , but instead , it was offered 40 G . 91R / 4s , which had originally been built for Greece and Turkey and which differed from the rest of the Luftwaffe G . 91s sufficiently to create maintenance problems in exchange for allowing Germany to build and use an airbase at Beja in Portugal for training . G . 91s arrived in Portuguese Guinea in 1966 , equipping " Esquadra 121 Tigres " based at Bissau , and being used for reconnaissance and close support with rockets , napalm and bombs against PAIGC rebels . When the PAIGC started to be supplied with Soviet - made Strela 2 ( NATO designation SA - 7 Grail ) MANPADS in early 1973 , these immediately became a threat to Portuguese air superiority . On 25 March 1973 , and 28 March , two FAP G . 91s were shot down by missiles within three days , with a further two lost to conventional ground fire later in the year . ( By comparison , only two G . 91s had been lost in Guinea from 1966 to 1973 . ) A final G . 91 was lost to a missile on 31 January 1974 , while Strelas were also responsible for the loss of a T - 6 Texan and two Do . 27 K - 2s . G . 91s deployed to Mozambique at the end of 1968 , equipping " Esquadra 502 Jaguares " ininitally at Beira , later moving to Nacala , with a second squadron " Esquadra 702 Escorpiões " ( Scorpions ) forming in September 1970 at Tete , flying against FRELIMO forces . Fremilo also received Strelas in 1973 , although unlike elsewhere , the Portuguese in Mozambique did not lose any aircraft to missiles with Chinese support , even if it forced Portuguese pilots to change their tactics . The only G . 91 destroyed in combat in Mozambique was the serial number " 5429 " , flown by Lt . Emilio Lourenço : his plane was destroyed and Lourenço killed by a premature detonation of its bombs while flying a strike against rebel positions on 15 March 1973 . In 1973 , with the United Nations weapons embargo against Portugal , the Air Force faced problems purchasing further numbers of close air support aircraft . An attempt was then made to acquire more Fiat G . 91s from Germany by having Dornier disassembling the aircraft and then selling them as spare parts to Switzerland and Spain . These spare parts would be later sold to Portugal and assembled locally with different serial numbers . However , the deal did not follow through as the German government vetoed it . In April 1974 , the Portuguese government fell in the Carnation Revolution , with the new government seeking to grant its colonies independence . Portugal withdrew its G . 91s from Guinea when it was granted independence in 1974 , with its forces also leaving Mozambique . One of the G . 91 squadrons was briefly deployed to Angola in late 1974 , in order to try to prevent fighting between rival FNLA and UNITA forces , being finally withdrawn back to Portugal in January 1975 . In 1976 , a second purchase of 14 G . 91 R / 3s and 7 G . 91 T / 3 trainers was made from Germany , which were followed by further aircraft when the G . 91 was withdrawn from " Luftwaffe " service in from 1980 to 1982 , giving a total of 70 R / 3s and 26 T / 3s , although not all of these entered service , with many being broken up for spare parts . Portugal finally phased out the last of its G . 91s in 1993 . Variants . Trainer and reconnaissance variants were produced right from the start of G . 91 production , but the basic design of the aircraft remained virtually unchanged throughout almost the entire production run of the aircraft . The one major difference is that the R series aircraft were single - seaters , while the T series aircraft had two seats . To accommodate the extra seat , the T series aircraft had a slightly longer fuselage . G . 91Y . An additional 67 aircraft built by Aeritalia were significantly uprated from earlier versions . These single - seat aircraft , designated G . 91Y and nicknamed " Yankee " , replaced the original Bristol Siddeley Orpheus engine with two General Electric J85 units . The G . 91Y first flew on 12 December 1966 and displayed an improvement in speed , range , payload , and manoeuvrability . The maximum speed was increased to 1 , 110 km / h ( 690 mph , 600 kn , Mach 0 . 91 ) . The machine guns were replaced by a pair of DEFA 552 30 mm cannon with 125 rounds per gun . All the aircraft built served with the Italian Air Force . Aircraft on display . There are numerous examples preserved in museums around the world .