In the darkened early hours of the morning of May 22nd 1982, a pair of Sea Harriers of No.800 NAS made their run along the deck of the ageing carrier HMS Hermes before leaping off the ski-jump mounted on the foredeck and in to the air. Armed for a combat air patrol, they carried a pair of AIM-9L Sidewinder missiles under their outer wing pylons while tucked under the fuselage in two streamlined pods were a pair of 30mm ADEN cannons. Their patrol route took them over Choiseul Sound, a stretch of water north of East Falkland island. Unbeknown to the two British pilots but a solitary vessel draped in camouflage was already traversing this stretch of water hoping to use the poor early morning light for protection from British aircraft. It was the Argentine Coast Guard (Prefectura Naval Argentina) vessel the Río Iguazú under the command of Captain Prefectura Olemda.
The Río Iguazú was one of twenty Z-28-class patrol boats built for the Argentine Coast Guard by Blohm & Voss in Germany during the 1970s. 90ft in length she displaced just 65 tons and had a typical crew complement of 15 while armament comprised of two browning 12.7 machine guns and various small arms carried by the crew. The vessel was dispatched along with her sister-ship the Islas Malvinas to the Falklands on April 11th still resplendent in their immaculate white paint schemes denoting that they were maritime security vessels. They arrived at Puerto Argentino (the Argentine occupational name for the Falklands capital Port Stanley) just after midnight on the 13th April and in doing so had violated the maritime exclusion zone established by the British following the Argentinian occupation of the islands on April 2nd. This meant that to the British the vessel was subject to attack without warning. On April 14th the crews of the two patrol boats began to paint over their white schemes with a brown and green camouflage pattern indicating that the Argentinians had every intention of using them in a combat role.
The Río Iguazú and the Islas Malvinas both carried out a wide variety of duties around the islands as the British taskforce sailed south and these ranged from security missions, escort missions, radar picket duties as well as providing pilot services to ships entering Puerto Argentino (Port Stanley). After the taskforce reached the Falklands on May 1st 1982 the ships also undertook a combat search and rescue role for Argentine pilots shot down in battle with the British. This put the two vessels in combat quite early in to the campaign when on May 2nd while both vessels were searching for a downed FMA IA-58 Pucara crew they were spotted by a Royal Navy helicopter. Early Argentinian reports that the helicopter was a Sea King proved false and it was in fact a Lynx helicopter operating from HMS Ardent. The Argentinian vessels and the helicopter both exchanged machine gun fire before the door gunner in the Lynx was wounded forcing the aircraft to withdraw. The two vessels, fearing further attacks, quickly withdrew also.
On the 21st May the first British forces landed at San Carlos and the ground war for the islands began. Later that very night Captain Olmeda received word that his vessel was to transport two OTO Melara 105mm howitzers and 15 members of the Army from Puerto Argentino to Goose Green to bolster the defences there. Some reports claim that the vessel was also carrying parts for Pucara attack aircraft, the only Argentine attack aircraft to operate from the islands themselves, although this is disputed. The equipment and the soldiers (who effectively doubled the patrol boat’s usual complement to 30) were loaded aboard under the cover of darkness. Due to the size of the patrol boat and the weight of the equipment it was carrying the artillery pieces had to be laid down flat across the deck to prevent the Río Iguazú from becoming top heavy. At 0430hrs on the morning of May 22nd the vessel slipped its moorings and set off for Goose Green via the Choiseul Sound.
At 0820hrs two Sea Harriers, XZ496 flown by Lieutenant Hale and XZ460 flown by Lieutenant Commander Frederiksen of No.800 NAS, passed over the Choiseul Sound. The murky low light of the early morning over the Falklands can give the islands a rather oppressive feeling but it meant that on the dark grey waters below the wake from the camouflaged patrol boat drew a short white line on the sea visible from the air. Hale signalled his intention to attack while Frederiksen stayed high to protect him from any Argentine aircraft that might try to intercept them.
The Argentine crew saw the two specs in the air and knew they were under attack. They quickly manned their action stations including the two 12.7mm machine guns and prepared to defend themselves. Hale flew in low and switched to his two 30mm cannons before strafing the vessel at a rather shallow angle. The shells struck the rear of the ship striking electrical equipment and damaging the rudder. Several shells also passed right through the hull causing the vessel to take on water. The loss of electrical power inhibited the crews ability to start pumping out the water.
The two 12.7mm guns on the Río Iguazú , manned by Corporal Julio Omar Benitez and Senior Assistant Juan José Baccaro, retaliated firing rounds at Hale’s aircraft during his attacks. Benitez and Baccaro were both hit with Beccaro’s gun being destroyed by a 30mm shell. As the Sea Harrier finished its last attack the one remaining serviceable gun was manned by Corporal Ibáñez who fired shots at the Sea Harrier. In the confusion of the attack the Argentine crew saw the Sea Harrier fly behind a plume of smoke and believed that Ibáñez had scored a direct hit bringing the aircraft down. This proved not to be the case however and both Sea Harriers returned to HMS Hermes.
Captain Olmeda knew that he could not pump out the water seeping in from the holes in his vessel fast enough to remain afloat and so he gave the order to drive the vessel on to the shore at Button Bay. The patrol boat beached and its sharply raked hull left to fall onto its starboard side. Despite the ferocity of the attack only Corporal Benitez was killed in the incident while Bccaro was seriously wounded and a few others sustaining minor injuries. Considering the number of men crammed aboard the vessel it is a miracle the death toll was not higher and Olmeda’s decision to beach almost certainly saved the remainder.
Despite the fact the patrol boat was taken out of the fight the howitzers onboard remained intact and the Argentinians wasted no time taking them off; they were afraid that a follow up attack might destroy the boat and its precious cargo completely. These guns were later used to defend Darwin from the advancing British before they were captured intact and used against their former owners. Efforts to refloat the Río Iguazú were impractical given the war situation and so Olmeda and his men abandoned the patrol boat at Button bay. The vessel was captured by the British who saw no use for it and so they too left it rot.
Then on June 13th a Royal Navy Lynx helicopter from HMS Penelope spotted the vessel unaware of its condition and believed it was an operational vessel. The Lynx fired a Sea Skua missile which struck the bridge destroying all of its internal equipment and damaging the superstructure beyond repair. This guaranteed that the vessel would never be returned to service. After the war the British towed the hulk off Button Bay and beached it for a last time at Goose Green. It was then broken up and sold for scrap. The name plaque of the Río Iguazú was presented to the Royal Navy and remains on display at the Yeovilton Fleet Air Arm museum.
Rio Iguazu photo credits: Patrulleras Argentinas