Russian shadow fleet: AIS manipulation has doubled
A data analysis shows: Ships of the Russian shadow fleet are switching off their tracking systems twice as often as before the Ukraine war. With great risks.
(Image: Korn Srirawan/Shutterstock.com)
Ships of the so-called Russian shadow fleet have been manipulating their positional data more than twice as often since the start of the Ukraine war. This is shown by a data analysis by NDR, WDR, and SĂĽddeutscher Zeitung together with international partners. The evaluation of AIS data (Automatic Identification System) documents a dramatic increase in signal failures for almost 1400 ships that Western security authorities attribute to Russia.
The AIS has been mandatory for larger ships since 2000 and, alongside radar, serves as a central instrument for collision avoidance. The system continuously transmits a ship's position, speed, and course to surrounding vessels and coastal stations. Especially in busy waters like the Baltic Sea, a functioning AIS is an important instrument for maritime safety.
Oil tanker was not locatable for almost 22 hours
The data analysis covers the period from January 2020 to September 2025 and considers positional failures that lasted longer than eight hours or extended over more than 200 kilometers. In the Baltic Sea alone, the number of documented failures increased from a few hundred in 2022 to several thousand per year. The journalistic organizations "Follow the Money" and "Pointer" processed raw data from Global Fishing Watch for this purpose.
Western authorities classify oil and gas tankers, which are allegedly used to circumvent sanctions, as well as cargo ships suspected of transporting weapons and sanctioned ships of Russian companies, as part of the Russian shadow fleet. One example is the 24-year-old oil tanker "Rangler," which was not locatable for almost 22 hours on its journey through the Baltic Sea in September.
According to "Follow the Money," ships attributed to Russia appeared with longer AIS failures six times more frequently than ships from various European countries.
Spoofing and targeted manipulation
The failures can be caused in various ways: the ship's crew can manually switch off the AIS, or the system can be manipulated through spoofing, whereby false positional data is sent.
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The problem fits into a larger picture of electronic warfare in the Baltic Sea. A current study on GPS interference shows that GNSS interference in the southeastern Baltic Sea region is becoming increasingly complex, with combined attacks of jamming and spoofing being used. According to experts, the AIS manipulation by the shadow fleet could also serve to protect against Ukrainian drone attacks.
Significant collision risk
According to experts, the signal failures increase the risk of collisions, as ships can no longer reliably locate each other. In early November, a spoofing incident demonstrated the extent of the manipulation: within minutes, thousands of ships appeared on tracking platforms like Marine Traffic in the Baltic Sea, including alleged warships and vehicles that had long since been scrapped.
While natural causes such as bad weather conditions or satellite coverage can occasionally lead to AIS failures, according to experts, these do not explain the massive increase since 2022.
(mki)
