Object found near area of San Juan’s last signal Satellite Calls on same frequency used by San Juanįaulty identification of possible banging on metal from passive sonarģ Flares seen in vicinity of last location Table 1: Summary of False Leads and Later Determined True Origin Date Table 1 summarizes these sources of hope that were later met with frustration. In the critical rescue window, multiple incidents hindered search progress by draining resources from follow-up investigations. 6 Yet, the most disappointing element to the abrupt search operation was the abundance of false signatures. In the rescue window, investigators battled swells that reached 10 meters and wind speeds in the South Atlantic recorded around 100km/h. Other obstacles included unfavorable weather conditions. 5 These sonobuoys offered a medium to hear distress transmissions from submarine, including via active sonar, underwater telephone, echo sounder, emergency location beacons, and hull tapping.

Over 11 countries sent nine ships and 13 aircraft to the search area, but the additional manpower and vessels arrived by November 21 st (T-3 rescue window), requiring aerial-deployed sonobuoys to spearhead localization efforts – not side-scan sonars. Moreover, the remoteness of the search area and the tardiness in support diminished the probability of success. 4 The ARA San Juan only had a submerged oxygen supply of seven days, giving a five-day rescue window after the last communication. It became apparent that space and time disadvantaged the emergency responders: The initial search box was larger than the size of Iraq. Argentinian Navy helicopters, U.S Navy P-8A Poseidon, and NASA P-3 Orion aircraft began search efforts with sonobuoys that possessed limited range, but which could be rapidly and widely deployed. Revisiting the initial search operations on the 17 th sheds light into the immediate challenges of the submarine search and rescue operations. 3 Although presumed beforehand, the imagery eliminated any possibilities that there had been survivors on the ARA San Juan.

2 Photographs taken by Ocean Infinity’s ROVs portrayed a compromised hull with propellers and a bow section discernibly separated.

On its one-year anniversary of the San Juan’s disappearance, Ocean Infinity – an American private seabed explorer company contracted by Buenos Aires – located the missing submarine 270 nautical miles off Argentina’s nearest coastal city at a depth of 2,976 feet – roughly three times the nominal test depth.

It furthermore underlines how contemporary submarine search tools – for rescue, post-mishap investigation, or espionage – remain underdeveloped and require further attention. 1 This case study examines the limits of aquatic-based forensic methods along with institutional shortcomings that inhibited the investigation. The boat transmitted its last signal on November 15th, 2017 and its failure to report twice to its command the next day prompted an international search and rescue operation starting November 17th. After completing a naval exercise near Tierra del Fuego, the diesel-electric submarine ARA San Juan (S-42) departed from the city of Ushuaia to return to its home port in Mar de Plata. The November 2017 disappearance of the Argentinian Navy submarine, the ARA San Juan (S-42), highlights the particular hardship confronting submarine recovery. In the race against time, recent history demonstrates that technology remains limited for submarine search and rescue efforts.

Underwater submarine rov