Chilean submarine Rucumilla

The vessel was originally ordered by the United Kingdom's Royal Navy as HMS H17, but was handed over to Chile in 1917 as H3.

As she began to submerge into the water, a valve for the battery ventilator was left open and allowed the boat to flood.

The escort Contreras (1896), a Viper-class destroyer, contacted immediately the authorities and the Chilean Navy reacted by sending three heavy lift cranes and other salvage ships to rescue operation.

At 14:00 the largest cranes (180, 60 and 30 t) were moved into position and slowly Rucumilla and her twenty five survivors began to rise.

The probe of the accident found that a valve with a rare left hand thread type caused confusion among the crew.