Showing posts with label ARA San Luis. Show all posts
Showing posts with label ARA San Luis. Show all posts

Sunday, June 7, 2026

Malvinas: The Performance of the Argentine Submarines

Argentine submarines in the Malvinas conflict

Alexander Mitrofanov || Top War



Submarine S-21 Santa Fe


At the outbreak of the armed conflict, the Argentine Navy had four submarines. Two of them, S-22 Santiago del Estero and S-21 Santa Fe, had been built in the United States in 1944 as SS-341 Chivo and SS-339 Catfish, respectively, and belonged to the Balao class. Between 1948 and 1949, Catfish was modernised under the GUPPY II programme, and in 1961 Chivo was modernised under the GUPPY IIA programme. In 1971, the submarines were transferred to Argentina. Santiago del Estero was decommissioned in 1981, and Santa Fe met the same fate between August and September 1982.


SS-339 Catfish in 1946


SS-339 Catfish after her modernisation, 1969.


SS-339 Catfish before and after the upgrade

The fleet also included two modern Type 209 submarines. These submarines were designed in West Germany by Ingenieurkontor Lübeck, Project IK-68, and their sections were built at the HDW shipyards in Kiel. In 1974, after being assembled in Argentina, the submarines S-31 Salta and S-32 San Luis joined the Argentine fleet. When used skilfully, these submarines represented a serious threat. A good example is provided by their sister submarines in the Peruvian Navy. During the inter-American Unitas-1996 exercises, for example, Pisagua sank the US SSN Narwhal six times, always being the first to attack the surface ships. In 2001, during the US-Peruvian SIFOREX-2001 exercises, a Peruvian submarine sank a US frigate. Since then, every year one of the Peruvian submarines has taken part in US anti-submarine exercises in the Atlantic, based at Norfolk.


Argentine Type 209 submarine

At the outbreak of hostilities, only S-32 San Luis was operational, while her sister, S-31 Salta, was undergoing repairs. She sailed in mid-April, but because of excessive noise, never entered combat. To replace the Balao-class submarines, the submarines S-41 Santa Cruz and S-42 San Juan were being built in West Germany to the TR 1700 design. The most experienced submariners were assigned to commission them, creating certain difficulties in manning the remaining submarines. Construction of four more submarines of this type was planned at a Buenos Aires shipyard. Had this plan been implemented, it would have given the military junta led by General Galtieri a very persuasive argument: eight latest-generation submarines.

Specifications S-21 Santa Fe S-32 San Luis
Displacement, t:
surfaced
submerged
1870
2340
1248
1440
Maximum length, m 93.9 55.9
Maximum beam, m 8.3 6.3
Mean draught, m 5.2 5.5
Hull design type double hull single hull
Operational diving depth, m 150 250 (max. 500)
Endurance, days ? 50
Number × power (type) of diesel engines, hp 4 × ? (General Motors 16-278A) 4 × 600 (MTU 12V493AZ80)
Number × power of electric propulsion motors, hp 2 × 2400 1 × 4600
Maximum speed, knots:
surfaced
under snorkel
submerged
18
9
15 - one hour, 6 - 34 days
10
11
22
Range (at speed, knots), miles:
surfaced
economical submerged
10,000 (10)
95 (5)
6000 (8)
400 (4)
Torpedo armament:
number of torpedo tubes (bow/stern) × calibre, mm
torpedo stowage (type)
10 (6/4) × 533
24 (Mk 14, Mk 37)
8 × 533
14 (SST-4, Mk 37)

Main tactical and technical characteristics of Argentine submarines

Actions of the submarine "Santa Fe"


In late March 1982, the Argentine Armed Forces launched Operation Rosario to recover the Malvinas Islands and South Georgia. Three naval forces were created for this purpose: a covering force, Task Force 20; a landing force for the Malvinas, Task Force 40; and a landing force for South Georgia, Task Force 60. Task Force 40 included a landing ship, two transports, two destroyers, two corvettes and the submarine S-21 Santa Fe. The submarine was assigned two missions: first, to land the tactical group Task Unit 40.1.1, made up of 13 naval special-forces combat divers, Agrupación de Buzos Tácticos - APBT, near Cape San Felipe, north of Port Stanley, to capture the Cape Pembroke lighthouse and Port Stanley airport — this mission was later cancelled — and to reconnoitre and mark the main force landing area, the "Yellow Zone"; the second was to patrol the assigned area.

Due to her poor technical condition, the submarine’s combat value was practically nil: worn batteries required a long time to charge and limited the time she could remain submerged, some of the torpedo tubes were inoperative and many systems were unreliable. The maximum diving depth was reduced to 120 m.

At 23:00 on 27 March, Santa Fe, under Captain Horacio Bicain and with an ARVT detachment commanded by Captain Alfredo Cufré, left the Mar del Plata naval base. Despite strong winds, the passage passed without incident on 28 March. The next day, taking advantage of improved weather, ARVT carried out a landing exercise with personnel in inflatable boats in sea state 2 to 3. Later, the wind increased to 40-50 km/h, prompting the order to delay the start of the operation by 24 hours, until 22:00 on 30 April; the landing had initially been scheduled for 1 April.

On 31 March, the submarine approached the north-eastern coast of Gran Malvina (East Falkland) to reconnoitre the currents and determine the landing area. The sonar operators detected the sound of a propeller, and periscope observations revealed lights on the shore, vehicle movement and a ship leaving Port Stanley; this ship was the Royal Navy’s A171 Endurance, en route to South Georgia.

On 1 April, the submarine commander received an order changing the combat mission, under which the APBT was to mark the "Red Section" landing area north of the previously planned landing zone. At 12:30 on 1 April, due to an electrical fault, the submarine lost radio contact, and at 17:30 the submarine and APBT commanders decided to begin the landing without waiting for contact with command. While approaching the coast at 23:50, the radar station failed and did not work again until 1:00 a.m. The landing took place north of Punta Celebronya, near Rinión Island. At 2:30, the APBT began boarding three inflatable boats, which set off from one side and reached the shore at 2:50. At 3:35, the reconnaissance and marking with signal lights of the main force landing area in York Bay was successfully completed. Shortly afterwards, the 2nd Battalion of the Argentine Marine Corps landed here from the landing ship Cabo San Antonio.


Routes of the Argentine naval force for the capture of South Georgia and the Malvinas Islands.


Capture of Port Stanley: 1 - Argentine landing in the Malvinas Islands; 2 - Reconnaissance by the submarine Santa Fe and marking of the "red section" of the landing between 02:30 and 03:35 on 2 April 1982; 5 - Landing of marines from Cabo San Antonio at 06:30 on 2 April 1982.

Santa Fe then moved to patrol area 080 San Felipe 60, 100 miles east of Port Stanley, before returning to Mar del Plata on 7 April. The trip back to base was not without incidents: communications were intermittent, the cooling system suffered constant failures, the bilge pumps could only operate at periscope depth, the main engines’ oil consumption exceeded all permitted limits, and the outer cover of the rubbish-disposal hatch jammed open.

Personnel from the Mar del Plata Naval Arsenal and Santa Fe worked non-stop for eight days to fix the problems and prepare the submarine for deployment. Twenty-three torpedoes, 20 Mk14 and the rest Mk37, fuel, fresh water and provisions for 60 days were loaded aboard. At that time, the arsenal had only 12 torpedoes of the required type, received from the United States along with the submarines, so the remaining torpedoes were provided by "friendly" countries — Peru? The Mk37 torpedoes could only be fired from the bow torpedo tubes.


Mk14 torpedo


Mk37 torpedo

Santa Fe’s main mission was to deliver 20 marines, Golf Group, armed with Bantam anti-tank missiles, recoilless guns and anti-tank grenade launchers to reinforce the South Georgia garrison, four tonnes of ammunition and equipment, and a new commander for the Argentine garrison on the island. The boat would subsequently patrol north of the island. Owing to uncertainty over the outcome of diplomatic negotiations between Britain and Argentina, Horacio Bicain was ordered to avoid engaging the enemy first, which considerably reduced his chances of success.

Santa Fe sailed from Mar del Plata at 23:30 on 16 April, and a few miles out new problems arose. The electrical control system of the propulsion system failed, leaving the boat adrift for three hours while repairs were made. The following day, the piston of diesel engine No. 1 failed, requiring 24 hours to bring it back into service. On 19 April, a failure in the cooling-pump gear caused diesel engine No. 4 to overheat. Emergency repairs with epoxy resins took 48 hours. This caused a delay in the planned landing.

On 20 April, due to bad weather, the submarine was forced to dive and continue the voyage submerged, which further delayed the landing. Between 21 and 22 April, despite a strong storm, Santa Fe continued surfacing, causing damage to the bridge rail and superstructure. The submarine submerged again. The damaged hull vibrated, interfering with the sonar system and revealing the submarine’s presence.

On 23 April they surfaced to find and remove the source of the noise. By then, the delay had reached 36 hours. That afternoon, the Antarctic patrol ship HMS Endurance intercepted a coded radio message indicating the presence of an enemy submarine, presumably Santa Fe, 100 miles from South Georgia. This caused some concern among the British command, as two British tankers were in the area transferring fuel from one ship to another.

The frigate HMS Plymouth was sent to the area to protect the tankers and escort them beyond the 200-mile zone. Admiral Sandy Woodward noted in his memoirs, One Hundred Days:

Tension was rising and the operation in South Georgia seemed to be stalled by fear of an Argentine submarine. Unfortunately, the range of our patrol aircraft from Ascension Island was insufficient.

The frigate HMS Brilliant and the nuclear submarine HMS Conqueror were sent to reinforce the British anti-submarine force heading for the island.

Santa Fe received information on the location of British ships near South Georgia from Argentine Air Force reconnaissance aircraft, C-130 Hercules and Boeing 707. For example, Endurance intercepted radio signals from the Boeing addressed to the submarine, indicating that it was heading towards the island to deploy special forces and had orders to sink Endurance.


HMS Endurance

In the early hours of 24 April, news was received that British forces had begun the liberation of South Georgia. Santa Fe’s commander received orders to speed up the operation. It was decided to head for Cape North, the western end of the island, and then to Cumberland Bay. The boat remained surfaced all night, submerged at 5:00 a.m. and snorkelled until dusk.

At 11:30 p.m., Santa Fe reached her destination and, stopping one mile from King Edward Point, unloaded Golf Group and the cargo between 2:30 a.m. and 4:30 a.m. using a motor launch captured from a British polar station. After completing the unloading, the boat’s commander decided to seek shelter in one of the many bays, carry out repairs and then proceed to the patrol area. But one hour later, when the boat was five miles from Grytviken, the administrative centre of the British Overseas Territory of South Georgia and the South Sandwich Islands, a battle alarm sounded: radar detected an approaching air target.


South Georgia

It was a Wessex helicopter piloted by Lieutenant Commander Stanley from the destroyer HMS Antrim. The destroyer’s sonar detected the noise of the Argentine submarine at a distance of approximately 50 miles. The helicopter dropped two Mk II depth charges, with fuzes set to minimum depth, which detonated off the starboard stern. The resulting damage prevented the submarine from diving. The submariners, in turn, opened fire on the Wessex with small arms.


A Wasp helicopter with an AS 12 missile


Wasp helicopter attacks Santa Fe


Depth-charge attack on Santa Fe

The Sea Lynx and Wasp helicopters from HMS Endurance, HMS Plymouth and HMS Brilliant arrived shortly afterwards, launching a Mk 46 torpedo, which passed beneath the submarine’s hull, and attacking her with AS 12 missiles and machine-gun fire. Three AS 12 missiles struck the fibreglass structure of the conning tower but did not detonate, disabling the snorkel and other retractable devices and seriously wounding a crew member. To avoid further casualties, Bikain ordered the crew to take shelter inside the pressure hull and, at 7:30, approached the quay at King Edward Point using a periscope.

Under cover of fire from the Argentine marines, the submariners abandoned their boat and took refuge ashore. A few hours later, the South Georgia garrison surrendered to the British with virtually no resistance; the island had been called San Pedro for only 23 days. The only fatal casualty of the operation was a Santa Fe sailor, who was immediately evacuated by helicopter to Antrim, where he underwent a successful leg-amputation operation.


A Sea Lynx helicopter with a torpedo slung underneath.


Frigate HMS Brilliant

The captured Argentines were housed in a building near the quay. Santa Fe’s commander requested permission for several members of his crew to return aboard the submarine to collect personal belongings, food and medical supplies. The request was granted, and half a dozen petty officers, escorted by British marines, boarded the submarine. Some managed to enter the heads and the galley and open the water-system valves to flood the submarine. The next day, the British decided to re-moor the boat about 400 metres from the quay of the old whaling plant in Grytviken, since the ammunition and batteries aboard posed a serious danger. In addition to the submarine’s commander, six other crew members took part in the mooring, supervised by a group of British marines. By then, the submarine’s stern had begun to sink, and a rotary blower was used to empty the ballast tanks and maintain buoyancy. Propulsion was provided by electric motors, using remaining electrical power. During the re-mooring, a tragedy occurred: Petty Officer Félix Artuso, who was operating the compressor and the diving-and-surfacing system valves, was killed. The English sentry, unfamiliar with submarines, mistook Artuso’s rapid movements — he had to operate 24 valves simultaneously — for an attempt to sink the submarine. The submariner did not understand English and did not respond to the warnings. The sentry fired a burst from his Sterling submachine gun.


Félix Artuso

Under these circumstances, the mooring was cancelled and, a few days later, Santa Fe sank at her mooring in 20 metres of water, listing to port. Only the superstructure railing remained afloat. The deceased submariner was buried with military honours in the local cemetery. The remaining crew members were transferred aboard the tanker RFA Tidespring to Ascension Island, and from there a chartered KLM aircraft flew to Montevideo.


The funeral of F. Artuso in Grytviken cemetery.


Santa Fe semi-submerged at the Grytviken quay.

After the end of the war, the British Ministry of Defence decided to refloat Santa Fe, which was obstructing the quay and, moreover, whose torpedoes and other ammunition aboard posed a serious danger. Work began at the end of June and was carried out by the crews of Endurance, the tug Typhoon and the salvage vessel Salvageman. Their task was to pump the water from the flooded compartments using portable pumps and, subsequently, to empty the ballast tanks with the compressed air remaining in the submarine’s cylinders. The situation was complicated by the virtual absence of submarine-engineering specialists; only two Endurance officers, a hydrographer and a supply officer, had served briefly in a submarine. There were also no plans of the submarine. Nevertheless, after more than two weeks of intense work, Santa Fe was afloat again, albeit with a 25-degree list.


Santa Fe alongside Salvageman after the boat had been raised.

This is how Endurance’s commander, N. Barker, described the scene that unfolded before the British sailors:

We also discovered a considerable collection of weapons, including torpedoes, mines, boxes of small arms, ammunition and explosives. Four homing torpedoes were piled up in the bunks, as if they were plague victims. A large number of torpedoes were stored on racks, in the removable deck flooring and in the torpedo tubes. One of the tubes was empty; they were probably trying to sink one of our ships, and it may have been us!
On 15 July, a team of specialists arrived from England to inspect Santa Fe, which had been pumped out. We all recognised a serious problem: the large quantities of TNT, which were drying out rapidly, were becoming increasingly unstable. Thanks to our efforts, Santa Fe had become a floating time bomb.


The divers prepare to inspect Santa Fe.

Therefore, it was decided to tow the vessel to a safer place and beach her there with the hatches and bulkhead doors open. It was believed that this would gradually flood the compartments and make the wet TNT safe again.


Santa Fe is being towed to the beach.

Between 1984 and 1985, after four months of work — the divers made 868 dives — the RMAS rescue ships Goosander and Salvageman, using 10 inflatable pontoons, refloated the submarine on 11 February 1985 and, after removing harmful substances, including diesel fuel, attempted to tow her to deep water away from the coast on 20 February 1985, Operation Okehampton, but the submarine sank 5 miles north of South Georgia at a depth of 350 m.


Raising of Santa Fe


Santa Fe is being towed to the sinking site.

To be continued ...

Wednesday, September 25, 2024

Malvinas: Captain Azcueta and the ARA San Luis Performance

“I am ready”: the Captain’s Courage the Day the Firing Computer of the ARA San Luis Submarine Broke Down in Malvinas

The recovery of the Malvinas Islands on April 2, 1982 took the commanders of the submarine force by surprise, as they had not been informed of Operation Rosario. Nevertheless, they prepared as best they could a submarine with serious technical deficiencies and sailed with it within the exclusion zone. The decision of Frigate Captain Fernando María Azcueta and his inexperienced crew. And the order to destroy the enemy with the only possibility of firing torpedoes manually.

By Mariano Sciaroni || Infobae


The drumbeat of war on April 2, 1982 surprised the ARA San Luis (S-32) and all its crew, including its commander, Frigate Captain Fernando María Azcueta, 40 years old and son of one of the first submariners of the Argentine Navy. It was docked at a pier at the Mar del Plata Naval Base (BNMP), base of operations for the Navy's small submarine force.



ARA San Luis departs from Mar del Plata Naval Base

The surprise was due to the fact that the high naval command, in order to maintain the secrecy of the operation carried out that day, chose not to inform the commanders of the various units not directly involved about Operation Rosario: the capture of the Malvinas.

Therefore, the San Luis did not receive the order to prepare for a combat patrol until 24 hours after the assault on the islands. At that time, the recently completed crew began to prepare the ship, in order to make it fit for war in the shortest possible time.

The initial state of the submarine was not satisfactory and it greatly needed to enter dry dock, something that would have to be done at the Puerto Belgrano Naval Base, the main base of the Navy, since Mar de Plata lacked such facilities.

The hull, propeller and internal cooling pipes of the San Luis had accumulations of small parasitic crustaceans, which affected its performance, increased its noise level and limited its speed. However, as there was not enough time to travel to Puerto Belgrano, the clean-up was carried out in Mar del Plata by divers (students from the Diving School) who worked 24 hours a day, equipped with manual scrapers, for almost a week.

Frigate Captain Fernando María Azcueta speaks to his crew during the 1982 war patrol. The beard indicates that they had already been at sea for quite a few days

Despite intense efforts before departure, several critical issues with the unit remained unresolved. One diesel engine had been out of service since 1976 due to a broken engine block, and the other three suffered from cooling problems that limited their power. Additionally, the snorkel frequently allowed seawater into the submarine, and the bilge pumps were unreliable. The DUUX system, a passive acoustic rangefinder, was deemed inaccurate and out of service.

Survival equipment also posed significant concerns. The life raft ejection system was non-operational, hydrogen burners were outdated, and the oxygen meter was being repaired on land. Gas measurement capsules, crucial for safety, had expired in 1976. This was particularly concerning given that the submarine was considered modern, having been incorporated in 1974.

The crew’s training level was compromised by the Argentine Navy’s personnel rotation policy, which resulted in many new and inexperienced crew members aboard. Key positions, including those in fire control systems, were held by junior non-commissioned officers, as the most experienced submariners were in West Germany overseeing the construction of new TR 1700-class submarines.

Lieutenant Luis Seghezzi, an exceptionally young Chief of Navigation, had just graduated from the Submarine School in late 1981. He reflected on the high turnover among the crew, acknowledging that most had only been on board for three months and that this was his first experience with the submarine's weapon systems. He noted that while high turnover allowed for more personnel to be trained in new technologies, it did not necessarily ensure better responses in unprecedented situations, such as those faced during the mission.

 

ARA San Luis's trajectory from the "Enriqueta" area to the exclusion zone, finally entering the "María" patrol area, within the Exclusion Zone
 

While the senior officers of the San Luis had extensive experience with submarines, neither Captain Azcueta nor his second-in-command had any with Type 209 submarines like the San Luis. Azcueta himself had only spent 16 days at sea as commander before the war began, having taken command on December 19, 1981.

On April 11, late in the afternoon, the submarine, fully loaded with water, provisions, 10 SST-4 guided torpedoes, and 14 Mk 37 Mod 3 torpedoes, set sail from Mar del Plata with its 35 crew members. Second Corporal Eduardo Lavarello recalls the departure on that Easter Sunday as a cold, foggy evening, which was ideal for remaining undetected as they headed out to sea.

By April 13, Captain Azcueta reported the results of engine tests to his superiors, confirming that the engines operated acceptably up to 1200 amps, achieving a maximum submerged speed of 20 knots. Despite the numerous challenges—limited experience with the Type 209, an inexperienced crew, mechanical issues, and unreliable weapons—Azcueta's message concluded with the resolute words, “I am ready.” This declaration, made in the face of daunting odds and the prospect of confronting the world’s leading navy in anti-submarine warfare, encapsulates the captain’s bravery and determination.

On April 17, 1982, after an uneventful transit during which the captain continued to train his crew and address mechanical issues, the submarine received a coded message. They were ordered to proceed to a waiting area designated as “Enriqueta,” located southeast of Golfo Nuevo, near the Argentine mainland and just north of the British-established Exclusion Zone.




The VM-8/24 computer is out of service

Initially, due to ongoing diplomatic negotiations, there were strict Rules of Engagement that limited the use of weapons, similar to those imposed on British forces. Weapons could only be used within the Maritime Exclusion Zone and after positively identifying a target, except in cases of submerged contacts, which were presumed to be enemy vessels.

Two days later, the VM-8/24 fire control computer on the ARA San Luis failed completely, despite the crew's efforts to repair it. Captain Azcueta later explained that the computer lost its display and the target panels became unresponsive to sensor commands. The crew attempted multiple troubleshooting steps, including checking power supplies and adjusting voltage levels, but the computer remained largely nonfunctional, though it could still operate in a limited emergency mode.

The fire control computer is critical for a modern attack submarine, as it processes sensor data, calculates firing solutions, and controls torpedo guidance. The VM-8/24 system on the San Luis could track and prepare solutions for up to three targets simultaneously, integrating sonar, radar, and periscope data to determine positions and vectors.

The computer’s failure was a severe blow, leaving the submarine unable to use its automatic fire control system. This limitation meant that the San Luis could only fire a single torpedo at a time, which had to be manually guided by the crew, significantly reducing the submarine’s combat effectiveness.


With the breakdown of the computer, according to the post-war report, there was:

  • Loss of the ability to automatically and instantly update the positions of the submarine, target and torpedo.
  • Loss of the ability to accurately calculate the Aiming Angle (Torpedo Course) and its instant update.
  • Poor precision of the manual guidance system dial (graduations every 5° by design)
  • Practical impossibility of estimating the position of the torpedo and, as a consequence, serious difficulty in introducing effective corrections.


The seriousness of the breakdown led Azcueta to break the traditional radio silence with which submarines move and inform his superiors. The Commander of the Submarine Force (COFUERSUB) recognized the problem, but decided not to withdraw the ARA San Luis from the waiting area, after assessing the convenience of having at least one submarine patrolling despite the limitations it faced.

According to doctrine, the failure of the computer implies a “low probability of impact” and, therefore, the use of torpedoes is “in case of defensive launches and if no other weapon is available”. Therefore, it was considered that the failure of the computer implied “that the fulfillment of the unit's mission would be practically unfeasible”.


Inside the San Luis, however, and despite knowing the new limitations with which they would go to war, they were somewhat optimistic. As Lieutenant Ricardo Alessandrini, the submarine's Chief of Armament, recalls: “The firing control computer was not operational and left us short of capacity in the waiting area. This limited the number of torpedo shots that could be controlled from the submarine. However, in the submarine force we often practiced the old-fashioned method of firing torpedoes using manual calculations and it was entirely possible to carry out a successful attack with good information about our target.”

That is, the S-32 crew would launch torpedoes using plottings and abacuses, in the same way that straight-running torpedoes were launched at short distances until the beginning of World War II.

Captain Azcueta also narrates: “As has been said, during the stay in the Enriqueta area, we took advantage of the stoppage to intensify the training in the different roles and to adjust ship values ​​that we had not updated. Among them the so-called “cavitation threshold”. In a submarine, the speed at which its propellers cavitate (a fluid phenomenon that produces an undesirable and significant noise of its own), depends on the depth and increases with it. That is, if I increase the immersion plane, I can apply more speed without cavitating. With resignation we verified that, whatever the depth, up to 150 meters, we cavitated at 6 knots. This circumstance led me to be very cautious with the speed in the patrol area. It became evident that, despite the great effort of the student divers of the Diving School, the propeller had not been sufficiently cleaned. There was nothing to be done.

By April 26, the negotiations on the fate of the islands were practically closed. COFUERSUB (Command of the Submarine Force) decided to send the San Luis to the “María” patrol zone, located north of the islands. It arrived there on the 28th, not without danger.

In the afternoon of the same day, with the deterioration of the military and political situation, the S-32 received the order to destroy any enemy target if it found it within the Exclusion Zone around the islands: “From COFUERSUB to San Luis. I cancel restrictions on the use of weapons. All contact is enemy.”

Even with all the problems mentioned and a broken firing computer (the brain of the submarine), the San Luis would cover itself in glory in the days to come. Admiral Brown would have been proud of this brave Navy lad.

Friday, December 8, 2023

Malvinas: ARA San Luis Heros

ARA San Luis War Patrol  - 1982

Source: Malvinas: Tras los submarinos ingleses 

 
Lieutenant Commander Ricardo Alessandrini, Chief of Armaments and Lieutenant Alejandro Maegli, Chief of Communications

 

The ship's crew at the end of the 1982 naval year




Lieutenant Commander Alessandrini, in a wet suit, ready to check some noises coming from the free movement area of the submarine


Lieutenant Commander Alessandrini, Lieutenant Commander Luis Seghezzi, Corvettte Captain Macías y Lieutenant Maegli


Lieutenant Commander Jorge Dacharry, Electricity Chief, LC Seghezzi, Navegation Chief  y Lieutennat Maegli



Lieutenant Commander Maegli (in the periscope) y Lieutenant Fernando María Azcueta, Submarine Commander


The Commander, Frigate Captain Azcueta, harangues the crew, once the decision to return to port has been made.



Part of the crew of the San Luis, shortly after returning to port

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The commander of the Submarine Force reviews the crew of the submarine, as soon as it arrives in port


Damián Riveros

Malvinas: Tras los submarinos ingleses 

Thursday, November 2, 2023

Malvinas: ARA San Luis against the Royal Navy

One Against All Odds


 

The secret history of the ARA San Luis submarine in Argentina in the Malvinas War

Jorge R. Bóveda 



The ARA San Luis was one of two submarine units sent in early April 1982 and the only one to face the powerful British task force face to face. Its modern technology and sophisticated sensors predicted that in the short term, losses would be terrible for the enemy. Inexplicably, after 74 days of fighting, no British ship was sunk by an Argentine torpedo. This document aims, based on the testimonies of the protagonists, to shed light on the dramatic 39 days of patrol, in which the ARA San Luis disputed (unsuccessfully) the naval supremacy of the Royal Navy in the South Atlantic.

Therefore, the testimony of an unprecedented battle between "David and Goliath", which projected beyond the conflict, provides valuable conclusions that can be drawn for the future of Argentine submarine weapons.
The brave performance of the ARA "San Luis" in extreme adversity, against an enemy many times superior in quantity and quality of anti-submarine means, demonstrates the high quality of the crew. San Luis's incredible ability to overcome such adverse circumstances is part of the most deeply rooted traditions of the Argentine Navy and, without a doubt, will be an example for new generations of submariners.


Since his retirement from active duty in 1995, the former commander of the ARA San Luis, Captain (RE) Fernando María Azcueta, has cultivated a low profile and the thorny issue of the conflict in the South Atlantic is rarely addressed outside his circle. of friends.

A few years ago, Azcueta rejected a tempting offer to put to paper his war experiences and the many interviews he gave. Since then, the subject was never addressed with all the details that are revealed in the following story, which shows for the first time, some dramatic situations of the 39 days of patrol, in which naval supremacy plays with the Royal Navy in the Atlantic South


Lightning preparation

When frigate captain D. Fernando María Azcueta, son of a prominent diver, took command at the end of December 1981, the modern 209 class submarine ARA San Luis, the hands of frigate captain D. Miguel C. Miguel C. Really, I couldn't even imagine that in just over three months, a war will be waged against the third naval power in the world.

And even less could he have foreseen the serious operational limitations that his unit suffered, and this could seriously compromise his effectiveness as a combat unit.

In mid-March 1982, while Azcueta and his men were exercising with the A-69 corvettes ARA Drummond and ARA Granville, on the coast of Mar del Plata, he received the order to stop the commission and return to port, but without receive no explanation for this unusual purpose.

Shortly after, he highlighted that the ARA Santa Fe was being prepared at the Naval Base, under the command of Lieutenant Commander Horacio Blicaini, but he did not receive any information that could alleviate the tremendous uncertainty that existed.
Only on the morning of April 2, Argentina's landing in the Malvinas was revealed to the public on radio and television throughout the country.

However, Azcueta had to wait another 24 hours to be received by COFUERSUB (captain Eulogio Latrubesse Moya), who gave the order, "Prepare in the shortest possible time to suspend (set sail)." From that moment he began a frantic race against time to see how the crew embarked with the best possible operating conditions.

 
In the image above you can see the San Luis at its base, with the aircraft carrier 25 de Mayo appearing in the background

The problems before departing

During sea trials carried out in the waters near the submarine base, the first of a series of problems was discovered when it was discovered that the San Luis could not develop a diving speed of more than 14.5 knots.

Closer inspection revealed that not only was the ship's hull and propeller covered with incrustations of small crustaceans known as "limpets" or "dog teeth," but the diesel cooling pipes were as well. This caused the engines to stop due to overheating, due to the lack of cooling water flow.

As there was no time to put the ship in dry dock to clean the hull - given the urgency of the departure - Azcueta had to turn to students from the nearby diving school, using shallow respirators as a "hookah" and do the scraping the hull "by hand" in rotating shifts of eight hours of continuous work, "to rid the hull of pests."

One of the causes of the problem originated in 1974 with the construction of the "wall" that separates the submarine dock from the civil dock in Mar del Plata.

This was built to prevent the new 209 class submarine from crashing into the dock in periods of rough seas, remaining tied up, a bad experience that had been experienced with the old "Fleet" type submersible and the veteran "Guppy", but that thanks to its design, the port had been "reconsidered", which allowed the detention of the ship.

Although laudable, the construction of a wall caused ecological changes with the lack of seawater circulation, which favored the formation of large colonies of barnacles, which had since settled in submarines docked at the dock.

On the San Luis, of the four diesel engines, only three were working, increasing the time to recharge the batteries and the exposure of the snorkel, making her extremely vulnerable to enemy search radar emissions.

The No. 1 engine had failed in early 1974, shortly after joining the Submarine Force. To repair it, it was necessary to cut the strong hull, a technology that the Argentine Navy did not have at the time.

TF Somonte, head of the ship's main propulsion, together with the Army Material Directorate and Tandanor, had managed to "free" the engine, using it until the end of 1978, when they decided to keep it out of service for safety reasons.

To make matters worse, neither the commander nor the submarine's chief weapons officer had had access to a report in mid-December 1981, which detailed the outcome of torpedo launches by the "Skip" class submarines during the period covered. between August and December of that same year, with special emphasis on the development of the exercise with the SST-4 torpedo.

The report showed that of all the launches made during this period, only once had the torpedo completed the run as planned.

A surprising percentage of launches were irregular, as a result of various factors (e.g. alteration in cable orientation, flooding of the torpedo, breakage of the strap, etc.), no one could identify the causes that led to the weapon's malfunction. .

The report in question had been released by the office of the Commander of the Sea Fleet, on which the Submarine Force depended, having failed to reverse the situation. As we will see later, the real causes of the problem would only come to light after the conflict.

Despite these serious limitations, Azcueta was heavily pressured by the political/military context in which he lived; he reported that he was able to put to sea on April 11.

The submarine sailed through the night, its small rooms stocked with food and water for a protracted war patrol, with 10 German-made SST-4 anti-surface torpedoes and 14 American MK-37 Mod. 3 anti-submarine torpedoes.

His rules of engagement prohibited him, until that moment, from any confrontation with enemy units, since it was believed that it was an offensive action that would jeopardize the negotiations that were taking place in the United Nations.

The transit to the area of operations in the Malvinas was used to carry out some minor repairs and continue with the training of personnel in the use of passive sonar, on which the survival of the submarines would depend from now on, having the latter to operate within a maritime zone completely controlled by the enemy.

On April 17, ARA San Luis arrived safely in its "fixed sanctuary" or holding area, designated with the code name "Enriqueta."

PART II: "At a disadvantage from the beginning"


Poder Naval