Disappearance of ARA San Juan

On November 15, 2017, the Argentine submarine ARA San Juan disappeared off the coast of Argentina while on a training exercise. After a search lasting fifteen days, the submarine and its crew of 44 - including Argentina's first female submariner - were declared lost. It is the worst submarine disaster since the loss of the Russian Kursk in August 2000.

Background


ARA San Juan (S-42), a diesel-electric submarine in  service with the Argentine Navy since 19 November 1985, was built in Germany by Thyssen Nordseewerke. She was laid down on 18 March 1982 and launched on 20 June 1983. San Juan underwent a mid-life update from 2008 to 2013, which included replacing all battery elements.

In early November 2017, San Juan was part of a navy exercise in Tierra del Fuego which included the sinking of the ex ARA Comodoro Somellera as a target. With the war game completed and after a short visit to Ushuaia open to the public, the submarine got underway to her home base at Mar del Plata.

Disappearance and rescue efforts
On 17 November, it was announced that she had not been heard from since 15 November, and that a search and rescue operation had been launched 200 nmi southeast of San Jorge Gulf. There were at least 44 servicemen on board the missing submarine, including Argentina's first female submarine officer, Eliana María Krawczyk. The submarine carried oxygen for no more than seven days when submerged.

On the same day, Argentine president Mauricio Macri moved to the official residence at Chapadmalal, near Mar del Plata, in order to follow the search and rescue operation more closely. The Argentine Armed Forces set up a centre of operations at the naval base in Mar del Plata, with family members of the submariners also present at the base. The Argentine Navy brought in a team of mental health professionals to aid the families; a team to keep them updated on the search and rescue effort had also been set up. Also on 17 November, the International Charter on Space and Major Disasters was activated by the Secretaría Nacional de Protección Civil de Argentina, thus providing for humanitarian satellite coverage.



On 18 November, the Ministry of Defense reported that there had been attempts at communication that day from a satellite phone that was believed to be from the submarine, but it was later determined that the calls were not from the vessel.

On 19 November, the Argentine Armed Forces stated that severe weather with 8 m waves in the area was hampering the search effort and that weather conditions would not be favourable until 21 November.

On 20 November, the Argentine Navy announced that the "critical phase" for the rescue was approaching. Though the submarine had enough supplies to last 90 days above water, she only had enough oxygen for 7–10 days submerged and it was speculated that she was submerged when communications were lost given the rough weather. The Navy also stated that if the issue had simply been a communications failure, then San Juan would have arrived at Mar del Plata on 19 or 20 November. The Argentine Navy later reported that sonar systems on two of its ships and sonar buoys dropped by a US P-8A Poseidon aircraft detected noises possibly coming from San Juan; a senior United States Navy officer told CNN that this sounded like banging on the hull in order to alert passing ships; later analysis of the audio determined that the sound "did not correspond to a submarine", and was probably of biological origin. By the end of the day the oceanographic vessels of the Argentine Navy ARA Puerto Deseado and ARA Austral with support of the icebreaker BRAZILIAN ICEBREAKER Almirante Maximiano of the Brazilian Navy carried out an extensive scan in the place where the biological sound started. The Royal Navy stated that 10 m waves had slowed the search, but easing weather led to improved sonar conditions.



As of 21 November, the search area was 482,507 km2 in size; 15 planes and 17 ships were actively searching the area. Weather conditions improved, with 3-4 m waves, making the search for the submarine less difficult. The United States Navy later reported that one of its planes had detected a heat signature which corresponded to a metallic object at a depth of 70 m, 300 km off the coast of Puerto Madryn. There was no official confirmation from the Argentine Navy whether the object was indeed San Juan, but sources told Clarín newspaper that a fleet in the area led by the corvette ARA Drummond was given orders to proceed "at full speed" towards where the object was detected. At 7:00 pm the British ship HMS Protector (A173), in her maritime patrol area, had seen three flares to the east: one orange and two white. This information was reported to Puerto Belgrano where the Search and Rescue Coordinating Center is set up. The Argentine Navy later determined that both the flares and heat signature were false leads.

On 22 November, the Argentine Navy investigated a "hydroacoustic anomaly" identified on 15 November, three hours after the last contact of the lost submarine; ships and airplanes were sent back to the last contact point with ARA San Juan. During a search flight over the South Atlantic, a U.S. P-8A Poseidon aircraft detected an object near the area where the missing submarine sent her last signal. The plane returned to base in Bahía Blanca late the same day.

On 23 November the Argentine Navy said an event consistent with an explosion had been detected, on the day the submarine lost communications, by CTBTO seismic anomaly listening posts on Ascension Island and Crozet Islands (Lat -46.12 deg; Long: -59.69 deg). The Navy received information through the Argentine ambassador in Austria since the CTBTO is based in Vienna. The organization had been asked to analyse data from the search area by the Argentine government on the week of the disappearance, but no leads had materialised until 22 November when the CTBTO informed the government. In a press conference, the Argentine Navy stated that it had not ruled out any possibilities since the submarine had not been located yet, and a spokesperson requested that the media be more precise when reporting information following "imprecise information which affects the family members." The Navy added that it received information on the explosion on the afternoon of 22 November, adding that it would have concentrated search efforts in that area had it known sooner.



On 24 November, the search and rescue operation was reinforced by the Brazilian submarine rescue ship Felinto Perry. The arrival of a Russian Navy exploration aircraft was also expected. More than 30 aircraft and ships from Argentina, the United Kingdom, Brazil, the United States, Chile and other countries participated in the effort to find San Juan. In all, more than 4,000 personnel from 13 countries assisted the search, scouring some 500,000 km2 of ocean – an area the size of Spain.

On 26 November, the Argentine Navy said that "despite 11 days of searching, it doesn't rule out that [the crew] could be in an extreme survival situation" and were not willing to draw any conclusions until the submarine had been located. Weather conditions in the South Atlantic were again making the search difficult, with winds of up to 100 km/h.

On 27 November, Argentine Navy spokesman Captain Enrique Balbi revealed to the press that according to the submarine's last report from 15 November, San Juan 's snorkel leaked water into the forward storage batteries the day before, which ignited a fire. After quenching the fire, the crew disconnected the forward storage batteries. The submarine continued to move powered by the aft batteries.

On 30 November, 15 days after the San Juan went missing, the Navy declared the rescue part of the operation to be over, turning its attention to finding the submarine and not her crew. The loss of 44 crewmen constitutes the largest loss of life aboard a submarine since the Russian Kursk sank on 12 August 2000.

Search continues


Locating a distressed or sunken submarine can be extremely difficult as witnessed by the disappearances of the French submarines Eurydice (found 53 days after sinking) and Minerve (never found) despite the fact that both were lost close to the French mainland. The nuclear-powered USS Scorpion was located 5 months after sinking, largely thanks to data obtained from SOSUS. The Israeli submarine INS Dakar was located in 1999, 31 years after her disappearance.

As of 21 November, when including vessels and aircraft making their way to the search area, the Ministry of Defense stated that there were 27 ships and 18 aircraft participating in the search and rescue of San Juan. Of those, 18 ships and 5 aircraft are Argentine, with the remaining 9 ships and 13 aircraft belonging to the 11 other countries which have offered assistance. There are also tens of fishing vessels assisting in the search. The operation is carried out under the auspices of ISMERLO, an international organisation of over 40 countries set up in 2003 following the Kursk submarine disaster.

On 24 November, according to the Argentine Navy, 27 ships, 30 aircraft, 4,000 professionals from 13 countries participated in the search effort to the missing Argentine submarine, this was already the largest search and rescue operation in the history of the South Atlantic Ocean.

Political consequences
On 16 December, the Argentine Navy fired its Head of Naval Operations after the incident.