Expert says mystery object may be part of a torpedo
Tuesday 6th October 2026 on 17:45 in
Finland
A metal object found floating off Helsinki may be part of a torpedo, according to maritime historian and research diver Juha “Roope” Flinkman, Yle reports.
A fisherman spotted the unidentified object on Saturday evening, prompting a major response by authorities. Passenger traffic through Kustaanmiekka, a busy route for passenger ships, was halted while the object was identified. It was later towed to Santahamina.
Flinkman said the object’s elongated shape and diameter of just under 40 centimetres match the dimensions of a torpedo’s compressed-air tank. A watertight tank could float even if the pressure inside had escaped, he said.
He described the torpedo theory as his best guess, shared by several colleagues, rather than a confirmed identification. If the object’s diameter is greater than the 40 centimetres reported by authorities, it could not fit inside a torpedo’s body.
One possible source is a torpedo fired during tests from the Isosaari torpedo testing station, which operated from the 1930s until 1956. Torpedoes were meant to surface at the end of their runs, but the mechanism sometimes failed, leaving some missing. Corrosion can eventually cause parts to come loose.
Flinkman’s second theory is that the object is a pressure tank from a submarine wreck. Hylyt.net, a service that lists shipwrecks, records seven British First World War submarine wrecks in a relatively small area south of Harmaja, a lighthouse island near Helsinki.
The British submarines were in Helsinki harbour in spring 1918 when the German fleet began approaching the city. The British blew up the vessels to prevent them falling into enemy hands. Some wrecks were later raised for scrapping, and parts may have been left on the seabed. Dozens of Soviet submarines also sank in the Gulf of Finland during the Second World War, Flinkman said.
A less likely possibility is an ordinary expansion tank from a ship’s engine cooling system, if the object proves shorter than a typical torpedo tank. The Navy Command may provide a definitive identification at a later date.