Update: 2017 Gävle submarine incident may have been Russian incursion
In July 2017 an unidentified submersible was imaged underwater in Gävle harbour, Sweden, by a ship conducting a survey. The high-resolution sonar images clearly show the small craft. Initial reports confirmed that it was not a Swedish Navy submersible.
Speculation quickly turned to Russia. In particular, the Triton-NN submersible boat, was identified by quality analysts
The sonar imagery released at the time
Sonar imagery is tricky to interpret, things do not appear as they would with the naked eye. At the time, and until recently, I thought that the Swedish made JFD SEAL Carrier (aka Carrier SEAL) was the best fit.
Although a Swedish Navy operated example was ruled out, the manufacturer has some Carrier SEALs at the factory at any time. And it seemed reasonable that one of these factory examples might have ventured up to Gävle on testing.
I am now much less confident. Retired Swedish Navy Admiral, Nils-Ove Jansson, has published a book reinforcing the claim that it is a Russian Triton-NN. Based on analysis of the original sonar imagery (not just the images appearing online), the Carrier SEAL was ruled out, and Triton-NN implicated. I do not have access to this original imagery. However combined with other information I have seen, I no longer believe that it was a Carrier SEAL.
By implication, a Russian submersible is most likely. And Triton-NN is the main suspect although I have been unable to confirm that the Triton-NN ever entered production. And Russia has access to other submersible boats and the ability to build unreported types.
The implications of this incursion are significant.
A spokesperson for the Swedish Navy has stated that they do not believe that it is an underwater vehicle. So maybe it’s a fuss about nothing.
Related articles (Full index of popular Covert Shores articles)
Triton-NN Submersible Boat
Naval Spetsnaz in Hybrid Warfare (Russian SDVs and DPVs)
Analysis of Swedish submarine incursion- Luleå 1983