Serious disruption of the GPS signal over Poland. Experts have no doubt who is behind it

Over the weekend, GPS signal interference began again over Poland. Maps from the GPSjam.org website show that problems occurred in approximately 2/3 of the country – from Gdańsk to Częstochowa. In the south, disruptions were within the norm, but the worst was in the north-east of Poland, where disruptions were severe.

GPS interference. Experts have no doubt that Russia is responsible

Disruptions have been occurring quite cyclically since December. . Dr. Michał Marek, a Ukrainian scholar and expert in counteracting disinformation, explains on his profile on X (formerly Twitter) that the Russians are taking advantage of the current disruptions and suggest that they are for the alleged transfer of troops by NATO, which is preparing for an attack. “In the Russian propaganda message, we are dealing with the activities of #NATO’s WRE systems, which are allegedly ‘probably related’ to covering up activities regarding the deployment of troops… NATO is allegedly ‘preparing’ for an attack…” – wrote Dr. Michał Marek on X

GPS signal interference is not only a problem for Poland, but also for other Baltic countries. Currently, problems still exist in large parts of Estonia. Other countries are less affected, but disruption may be felt in some southern parts of Sweden and Finland and in western Germany and Denmark.

GPS interference. Serious problems are unlikely, but possible

The occurrence of satellite navigation disruptions can be easily observed on the website gpsjam.org, created by John Wiseman, an amateur observer of air traffic and related events. The data powering the portal comes from a network of ADSBx radio amateurs who intercept and collect signals transmitted openly by civilian and sometimes military aircraft. They include, among other things, information from on-board systems about the quality of the satellite navigation signal. The website gpsjam.org collects this data and, depending on how many aircraft in a given area report problems with the accuracy of their navigation systems, it is marked as interference-free (green), moderate (yellow), or high (red). This last category means that more than 10 percent of machines report problems –

The risk of planes crashing for this reason is small. Civil aviation normally relies on satellites to locate aircraft in the air, but it can cope without it. Although it requires more effort and is less accurate. Interfering with satellite navigation signals therefore mainly means inconvenience, system load and delays.

A much more dangerous activity is cheating (English name: “spoofing”) by sending specially crafted signals to a specific satellite navigation receiver that will mislead it as to its location. This way, for example, you can make a plane flying on autopilot change course or make the crew make wrong navigation decisions because they believe they are somewhere different than they actually are. These types of incidents have happened, although they are very rare, because such cheating is much more difficult than general disruption.

Regardless, any interference with the operation of satellite navigation may, in extreme situations, have tragic consequences. In 2019, a U.S. plane almost crashed during an approach to land in mountainous terrain in Sun Valley, Idaho. The crew was guided by the on-board equipment as they flew into clouds of smoke from forest fires. According to the NASA report, due to strong GPS interference in this area, the plane deviated from the course and headed straight for a mountain peak. Fortunately, the air traffic controller noticed it on the radar and warned the crew at the last moment.

Tampering with satellite navigation signals is therefore an undesirable action. It is usually the result of military activity. Jamming is the result of some powerful transmitter on the ground sending signals on the frequencies used by navigation satellites. This makes receiving the right ones difficult or even impossible. The signals sent by satellites are weak, so receivers can be overwhelmed by spurious emissions from the ground. Activities of this type are of great interest to the military, especially the Russian one. NATO has significant amounts of equipment and weapons using satellite navigation. Therefore, limiting their effectiveness is of great importance. In practice, this can be observed on the battlefield in Ukraine. The Russians are trying to completely disrupt GPS in key locations to reduce the accuracy of Ukrainian weapons such as GMLRS missiles and JDAM bombs. Their actions are expected to bring noticeable effects, although creating a kind of security bubble within a radius of several to several dozen kilometers requires specialized electronic warfare equipment (WRE), which is always in short supply.

The Russian WRE (electronic warfare) troops are considered one of the most extensive and best in the world. They have numerous systems designed to disrupt GPS. The most frequently mentioned in this context are R-330Ż Żytiel, RB-301B Borisoglebsk-2 and Pole-21. However, the Russians have many other types of WRE systems, the real capabilities of which are not publicly known. The ability to jam GPS appears regularly in their advertising and propaganda descriptions.