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EASA warns of GPS jamming around conflict zone


Europe’s aviation safety agency EASA is warning aviation authorities, air navigation service providers and aircraft operators that jamming of global navigation satellite systems has been observed by aircraft around Russia and Ukraine, and is recommending that they adopt mitigation measures.

“In the current context of the Russian invasion of Ukraine, the issue of global navigation satellite systems (GNSS) jamming and/or possible spoofing has intensified in geographical areas surrounding the conflict zone and other areas,” said EASA in a safety information bulletin issued today.

A satellite navigation system with global coverage can be termed GNSS, and includes, for example, the United States’ Global Positioning System (GPS) and the European Union’s Galileo system.

Since 24 February, roughly four days after Russia invaded Ukraine, spoofing and/or jamming has intensified in four key geographical areas based on reports from Eurocontrol, EASA’s own Network of Analysts and open-source data, according to EASA. These areas are: the Kaliningrad region and the surrounding Baltic sea and neighboring States; Eastern Finland; the Black Sea; the Eastern Mediterranean area near Cyprus, Turkey, Lebanon, Syria and Israel, as well as Northern Iraq.

Said EASA:

The effects of GNSS jamming and/or possible spoofing were observed by aircraft in various phases of their flights, in certain cases leading to re-routing or even to change the destination due to the inability to perform a safe landing procedure.

Under the present conditions, it is not possible to predict GNSS outages and their effects. The magnitude of the issues generated by such outage would depend upon the extent of the area concerned, on the duration and on the phase of flight of the affected aircraft.

Degradation of satellite navigation signals can cause a host of safety issues, including but not limited to the potential loss of area navigation (RNAV) approach capability; the inability to conduct or maintain required navigation performance (RNP) operations including RNP approaches; and, naturally, the loss of ability to use GNSS for waypoint navigation.

Signal degradation can also potentially trigger terrain warnings, “possibly with pull up commands”, warned EASA, and inconsistent aircraft position on the navigation display, as well as the loss of automatic dependent surveillance-broadcast (ADS-B), wind shear, terrain and surface functionalities, among other problems.

While the agency’s safety concern is not considered “an unsafe condition that would warrant Safety Directive (SD) action”, said EASA, it is recommending that mitigation measures be taken by stakeholders.

Air operators, including helicopter operators, are being urged to ensure that flight crews promptly report to air traffic control any observed interruption, degradation or anomalous performance of GNSS equipment or related avionics; assess operational risks and limitations linked to the loss of onboard GNSS capability, including other onboard systems requiring inputs from reliable GNSS signal; and remain prepared to revert to a conventional arrival procedure where appropriate.


National aviation authorities, meanwhile, should ensure that contingency procedures are established in coordination with air navigation service providers (ANSPs) and airspace users, and that essential conventional navigation infrastructure, particularly Instrument Landing System — which provides short-range guidance to aircraft — are retained and fully operational, said EASA. Mitigation measures such as the issuance of NOTAMs describing affected areas and related limitations should also be implemented, it recommends.

EASA also wants to see national aviation authorities and ANSPs establish a process for collecting information on GNSS degradations, and confirm ANSPs’ readiness to provide reliable surveillance coverage that is resilient to GNSS interference such as ground navigation aids for conventional non-satellite based navigation (it cites, for example, the ground-based VHF omnidirectaional range).

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