- In April 1982, Argentina seized the Falkland Islands from the UK, starting a war in the Atlantic.
- Royal Navy ships steamed south to recapture the islands, and the Argentine navy sailed to meet them.
- The naval clash involved aircraft carriers from both countries and almost ended with one being sunk.
Just before 3 a.m. on May 2, 1982, the Argentine cruiser General Belgrano was hit by two torpedoes fired by a British nuclear-powered attack submarine, HMS Conqueror.
The cruiser's electrical system was damaged and it was unable to send a distress signal. Within 45 minutes it sank to the bottom of the South Atlantic, taking 323 of its crew members with it.
At the time, Britain was at war with Argentina. That April, Argentina had seized the Falklands Islands, prompting the British to send a naval task force to retake the islands it had controlled since 1833.
The sinking of the Belgrano was only the second time since World War II in which a submarine sank an enemy warship, and it is one of the war's best-remembered moments.
While the Conqueror was firing on the Belgrano, another major naval encounter was unfolding a few hundred miles to the north. Argentina's only aircraft carrier, ARA Veinticinco de Mayo, was trying to find the British aircraft carriers accompanying the incoming task force.
The Argentines were unaware they were being hunted by two more British nuclear-powered attack subs.
An old carrier
Named after the date of Argentina's 1810 revolution, Veinticinco de Mayo was a Colossus-class fleet carrier built by the British and commissioned into service in 1945 as HMS Venerable.
It served with the British Pacific Fleet until 1947 and was sold to the Netherlands in 1948. In the 1950s, it was refitted with an angled deck and a steam catapult. After a mostly uneventful tenure with the Dutch navy, the carrier was knocked out of service by a boiler-room fire in 1968.
It was then sold to Argentina, which repaired and upgraded the carrier, commissioning it as the ARA Veinticinco de Mayo in 1969. At 630 feet long and 80 feet wide, it could carry up to 24 aircraft and had a crew of 1,300.
Veinticinco de Mayo supported the Argentine invasion of the Falklands on April 2, 1982, with an air wing of eight A-4Q Skyhawk combat aircraft, four S-2E Tracker anti-submarine aircraft, and two SH-3 Sea King helicopters.
Shortly after Britain announced its intention to retake the Falklands, Argentina's navy made plans to intercept the Royal Navy as it arrived in the South Atlantic.
Argentine ships were deployed in a pincer movement, swinging 200 miles to the north and south of the Falklands.
Veinticinco de Mayo, along with the Type 42 destroyers Hércules and Santísima Trinidad (also built in Britain) and the Gearing-class destroyer Comodoro Py, formed the northern part of the pincer. ARA General Belgrano and its two escorts formed the southern one.
A third Argentine task force of three Drummond-class corvettes, armed with Exocet anti-ship missiles, was also operating in the north, though farther away from Veinticinco de Mayo and its escorts.
On the night of May 1, aircraft from Veinticinco de Mayo detected the British fleet and prepared for an attack.
The most important targets were the two British carriers leading the flotilla, HMS Invincible and HMS Hermes, which carried about 20 Sea Harrier jump jets that were critical to the British operation.
But Veinticinco de Mayo's Skyhawks were unable to attack. When fully loaded with fuel and weapons, they needed wind to launch from the carrier, and there would not be any wind for at least 12 hours — a rarity in that part of the Atlantic.
The Argentines couldn't afford to wait and called off their attack. At midnight, a British Sea Harrier found Veinticinco de Mayo and its escorts. A few hours later, the Belgrano was sunk.
With the sinking of the Belgrano, Argentine commanders realized just how vulnerable their ships were — especially their carrier. They ordered their ships back to port. Unbeknownst to them, the British were already in pursuit.
9 days of high-seas cat and mouse
The British made it a top priority to knock Argentina's navy, especially Veinticinco de Mayo, out of the fight. Three nuclear-powered attack submarines of Task Force 324 were tracking the Argentines as the rest of the British fleet sailed south.
The task force consisted of HMS Conqueror, a Churchill-class attack sub, which was assigned to patrol south of the Falklands, and the Swiftsure-class attack subs Splendid and Spartan, which were assigned the northwest and northeast sectors, respectively.
The British, now aware of Veinticinco de Mayo's location, sent HMS Splendid after it, starting a nine-day chase.
Because of its lingering boiler problems, Veinticinco de Mayo was slower than the sub's top speed, but the carrier's zig-zag course through shallower waters forced the Splendid to slow down.
The Argentine ships also kicked their anti-submarine operations into high gear.
The carrier's escorts took up position 5 miles off its port, bow, and starboard. The four S-2E Trackers flew six-hour missions, flying as far as 100 miles from the carrier to drop sonobuoys and use their surface-search radars. They also used electromagnetic sensors to listen for radio signals going to or from the Splendid.
The two Sea King helicopters patrolled closer to the carrier, using dipping sonars that could detect submarines within 3 miles.
When the Argentines detected what they thought was a sub, they attacked with Mark 44 torpedoes or Mk 54 depth charges dropped from the Trackers.
Despite the Argentine defenses, Splendid closed in. On May 3, it was close enough to make visual contact with Veinticinco de Mayo's escorts. A day later, though it had to dive deep to avoid the Trackers, its sonar had acquired the carrier and its escorts.
By the time Splendid was within torpedo range, however, the carrier and its escorts had entered Argentine waters and continued sailing north.
The British wanted to portray their actions as purely defensive and decided not to attack Argentine forces in their own waters. Splendid broke off its pursuit and headed south, leaving the job of tracking the carrier to HMS Spartan.
On May 5, one of Veinticinco de Mayo's Trackers detected signs of a submarine. Numerous Mark 44s were fired but made no hits. Neither Splendid nor Spartan was in the area at the time, suggesting the Argentines had misidentified the contact or had instead detected a US, Soviet, or Chilean sub.
The hunt for Veinticinco de Mayo finally ended May 9, when the carrier entered the port of Viedma. It never sortied again during the war, but its Skyhawks, flying from land, helped sink the British frigate Ardent.
The naval clashes of the Falklands War were a glimpse at modern high-seas warfare and its toll.
Two days after Belgrano was sunk, the British destroyer Sheffield was sunk by an Exocet missile, becoming the first Royal Navy ship sunk in combat since World War II. While the main carriers escaped unscathed, a freighter the British converted to carry aircraft was sunk, also by Argentine anti-ship missiles.