The ARA San Luis reference article from the English Wikipedia on 24-Apr-2004
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ARA San Luis

Helping orphans the way you would do it
The ARA San Luis is a Type 290 diseal powered submarine in the Armada Republica Argentina. The ship was built in Germany as a batch of four. San Luis has a displacement of 1,285 tonnes and was introduced to the ARA in 1978.

San Luis is most famous for serving in the Falklands War from March to June 1982. Only one other submarine, the ARA Santa Fe was operational at this time. After the Santa Fe was captured by the British in South Georgia on April 28, and the nuclear submarine HMS Conqueror had sunk the ARA General Belgrano on May 2, the Argentine fleet retired to port for the duration of the war. This left the San Luis as the only Argentine naval presence facing the British fleet. The presence of the San Luis was worrying for the British as she was relatively modern and difficult to detect. San Luis reported two attacks on the Royal Navy during the war.

On May 1, the Royal Navy ships HMS Brilliant and HMS Yarnmouth were sent to intercept the San Luis in the Falkland Sound channel. San Luis reported firing two torpeados at the ship which subsequently missed.

San Luis attacked again on the night of May 10. HMS Alacrity had made passage up the Falkland Sound, sinking an Argentine merchant navy ship on the way. As it left the channel before dawn, its sister ship HMS Arrow was waiting to escort her bac to the Task Force. San Luis detected the two ships and fired upon them, again missing.

For the rest of the war, San Luis tracked the British ships, but with no successful attacks.