Designed and built as a counter-insurgency aircraft, the IA-58 Pucará, being rugged and dependable and able to fly from short rudimentary airstrips, found itself on the front lines of the Falklands War.
Promising Prototypes
Argentina realized in the late 1960s the need for a COIN (counter-insurgency) and anti-guerilla aircraft, and the Argentine Air Force, or Fuerza Aérea Argentina (FAA), put forth a requirement in Aug. 1966. Argentina’s state aircraft factory developed a low-wing monoplane twin-engine design. An unpowered version was tested, with gliding trials beginning in Dec. 1967. No handling issues were discovered.
Construction began by Fábrica Militar de Aviones (FMA) on a powered prototype in Sept. 1968. Designated the “Delfin”, it would later be known as the FMA IA-58 “Pucará”, named after the stone fortress strongholds built by the ancient indigenous people of the region. The all-metal aircraft would be powered by two wing mounted 904 horsepower TPE 331 Garrett AiResearch (Honeywell Aerospace) turboprop engines. It first flew in Aug. 1969 with good results.
A second prototype would fly in Sept. 1970, this time powered by Turbomeca Astazou XVIG engines of French design producing between 956 and 988 hp. Results were favorable, leading to the first prototype having these engines installed, and the engine was also chosen for the third prototype as well as the production aircraft.
Production Pucarás
The first production model, the IA-58A, would fly on Nov. 8, 1974. A crew of two was situated in tandem in Martin-Baker Mk 6 ejection seats, with the rear seat elevated 25 cm (9.8 in) above the front. Visibility was excellent due to the placement of the dual control fitted cockpit forward of the wings and near the nose of the aircraft. The canopy and cockpit, as well as the engines, were designed with protection from ground fire.
Sporting a slender fuselage and a high T-tail, the IA-58 also incorporated lengthy and sturdy tricycle landing gear, allowing the aircraft to carry a variety and quantity of external stores without them contacting the ground when operating from unimproved rough airstrips. The twin-wheel main gear retracted into the engine nacelles. The aircraft was designed to operate from a short runway, and using three JATO (Jet Assisted Take-Off) pods, that distance was decreased even more, as short as 80 meters (262 ft). The IA-58 weighs in at 4,000 kg (8,810 lb) empty with a maximum take-off weight of 6,800 kg (14,960 lb) Size specifications are 14.25 m (46 ft 9 in) in length, with a wingspan of 14.5 m (47 ft 6.75 in) and a height of 5.36 m (17 ft 10.5 in)
The Pucará had no internal weapons bay, with armaments other than the internal guns being mounted externally on pylons below the wings and the centerline of the fuselage. A variety of weapons could be carried by this aircraft at external hardpoints: various types of bombs, missiles, mines, gun pods, and rockets, single or in clusters, with ease. Up to 1,620 kg (3,570 lb) of external weapons and/or external fuel tanks could be carried.
Fixed armament included two Hispano 20 mm cannon mounted directly under the cockpit. Each Type 804 gas-operated gun had 270 rounds available. Four forward-firing FN Browning 7.62 mm (.30 caliber) machine guns were positioned with two flanking each side of the cockpit, each gun with 900 rounds available.
Performance was good for a straight-wing turboprop powered aircraft with external ordinance slung underneath creating drag, with a top sea level speed of 310 mph, and the ability to dive at speeds up to 469 mph bringing armaments to bear on ground targets. Turning radius was tight allowing the crew to keep a close eye on ground targets after being engaged. Service ceiling was 10,000 m (33,000 ft). Combat radius varied widely with a wide variation of payload and external tanks possible. The aircraft was equipped with self-starting engines, duplicated systems, and ease of access to major components to allow for operation from forward airstrips with minimal support.
Proposed Pucarás
With the IA-58A being the main production model, there were a few proposed variants. One was the IA-58B, with more advanced avionics and twin 30 mm cannons replacing the 20 mm cannons. Only one IA-58A was converted to this configuration.
The IA-58C prototype modifications included removal of the forward cockpit for installation of a single 30 mm cannon in addition to the standard armament of the IA-58A. Air-to-air and air-to-surface missile capabilities were enhanced, as well as increased armor. Anti-helicopter and anti-ship capabilities were increased. One IA-58A was converted to this configuration; plans for more conversions were dropped due to funding issues.
The IA-58D included updated existing IA-58s with newer avionics and PT6A-62 Pratt and Whitney engines rated at 950 hp.
A single IA-58A was fitted with two Garrett TPE-33-11-601W engines rated at 1,000 hp. It was known as the IA-66.
More from The Aviationist
The airframe was also used for experiments carrying torpedoes in an effort to bolster the anti-ship capabilities of the Argentine military. This prototype was designated AX-04.
Interdiction and Invasion
The IA-58A was used with success against lightly armed guerillas, insurgents, and against narcotic smuggling operations. Argentina was in a season of political turmoil in the 1960s and 1970s, both communist and fascist forces were conducting attacks, there were years of protest and instability. The IA-58 was an important tool in attacking anti-government forces and providing close air support, culminating in the 1976 “Dirty War”. This was a counter-insurgency campaign led by the military junta that seized power. The military went to work exterminating the revolutionary groups hiding out in the mountains and jungles. However, the Pucará would see even more action soon.
In April 1982, a long dispute over the sovereignty of at the time somewhat obscure islands in the far South Atlantic came to a head. Argentine military forces invaded the Falkland Islands (Malvinas) and South Georgia Island, which were under United Kingdom control. Argentina and the United Kingdom both laid claim to the territories, and several attempts to find diplomatic solutions had failed.
With a large British task force steaming towards the South Atlantic to possibly attempt to recapture the islands, Argentina began fortifications and reinforcement of the Falklands. Argentina had a fairly modern fleet of capable jet fighters, attack aircraft, and fighter-bombers in her arsenal, but they could not operate from the rudimentary rough and short airstrips on the islands. Distance, range, and aerial refueling capabilities also hampered the use of the jets. The solution was to station FMA IA-58 Pucarás on the island for use in ground attack and observation roles should the British invade.
The Pucarás with their rugged landing gear, short take-off and landing abilities, and capacity to carry a payload packing a punch seemed like the perfect solution. The aircraft’s narrow fuselage made it a difficult target for ground fire when facing it head-on, and its simplicity and ease of maintenance would be of benefit in a remote setting with harsh weather conditions.
A total of 24 of the approximately 60 IA-58s in Argentina’s arsenal at the time were deployed to the Falkland Islands, with others moved into positon along the coastal areas of Argentina in case reinforcements were needed. Falkland based Pucarás operated at airstrips at Port Stanley, Goose Green, and Pebble Island.
The British, aware of the ground attack capabilities of the IA-58, attempted to destroy most of the aircraft on the ground. On May 1, 1982, three Pucarás were destroyed on the ground at Goose Green by cluster bombs dropped by British Sea Harriers flying from British aircraft carriers, and six more destroyed on the ground by British SAS (Special Air Service) troops on Pebble Island on May 15. SAS troops also downed a Pucará with a Stinger SAM surface-to-air missile later in the month on May 21.
Also on May 21, 1982, an airborne IA-58A was engaged by a British Sea Harrier. The Harrier hit the Pucará with at least twenty 30 mm cannon shells before it went down, demonstrating the toughness of the aircraft and hence the name given to it.
After a barrage of around 161 naval shells fired from the HMS Arrow, a British frigate, it is reported that up to two IA-58 aircraft were damaged or destroyed at the airfield at Goose Green.
While it appears the Pucarás didn’t have much of a fighting chance in this undeclared war, the type is responsible for the only confirmed Argentine air-to-air victory of the conflict. On May 28, 1982, a pair of Pucarás shot down a British Royal Marines helicopter, a Westland Scout. One of the IA-58s crashed afterwards. In a separate incident, another IA-58 was shot down the same day by small arms fire at Goose Green. The pilots of the Pucarás harassed British troops with ground attacks, but in the end, the British prevailed and retook the islands.
After the Fight
The United Kingdom captured eleven Pucarás at the end of the conflict; six were taken back to the United Kingdom, one in flying condition was evaluated and afterwards placed in the Royal Air Force Museum, and four other examples exist in museums throughout the country.
The IA-58 was retired in 2019 from Argentinian counterinsurgency and ground attack roles and upgrades to the airframe led to the IA-58 Pucará Fénix project, to be used mainly for border patrol and surveillance.
The IA-58 has also seen service in Sri Lanka, Columbia, and Uruguay. The Pucará saw action in the Sri Lankan Civil War in the early to mid-nineties, Columbia used the aircraft for narcotics interdiction, and Uruguay used them to intercept drug runners and at one point to track cattle rustlers. Negotiations for sales of the aircraft to several other countries failed or orders were cancelled. With production ending in 1999, a total of approximately 110 Pucarás were built.
