GNSS JAMMING AND SPOOFING EVENTS PRESENT A GROWING DANGER

Last year, reports that fake signals were jeopardising aircraft navigation systems spiked in the area over the Black Sea. First reported by security intelligence organisation OpsGroup, the reports cited false or jammed global navigation satellite system GNSS) signals, affecting the US global positioning system GPS) civil signals, causing aircraft navigation systems to show missing or inaccurate position information.

More recently, an OpsGroup member reported experiencing GPS spoofing on 29 January after departing from Israel’s Ben Gurion International Airport (LLBG). “This lasted until the FIR boundary. ATC was notified and provided vectors to us instead.”

GNSS is an all-encompassing term referring to any satellite-based position, navigation and timing (PNT) system that provides information to receivers such as portable GPS units and those installed in aircraft. The US GPS is one such GNSS and there are others such as Europe’s Galileo, Russia’s Globalnaya Navigazionnaya Sputnikovaya Sistema (Glonass), China’s BeiDou and regional systems in Japan and India. Receivers can be made to operate on multiple GNSS constellations or just one. Most aircraft GNSS receivers use only the US GPS constellation, while many portable GNSS receivers and watches with GNSS capability tap into multiple constellations.

GPS jamming overwhelms relatively weak GNSS signals and in the US and many other countries, it is against the law to compromise GNSS. Spoofing is not the same as jamming and is more sophisticated, tricking the receiver into calculating a false position, which could send an aircraft off the desired course. Many modern avionics products rely on GNSS and jamming and spoofing can cause problems beyond navigation, such as the autopilot switching off.