On Cyprus, People Appear to Walk on Water and Swim Through Airports
In Cyprus, people can seemingly walk on water and swim through airports. They themselves don't notice it, but that's how their gadgets portray it. A jogger from the city of Larnaca shared on Reddit that after his run, his Garmin watch suddenly located him in Lebanon. Meanwhile, a swimmer who was enjoying the sea off the Cypriot coast appeared to have swum through Beirut's airport, according to his smartwatch.
Cypriot delivery services and taxis sometimes fail to reach their destinations. Dating apps suddenly seem geared toward long-distance relationships. While these glitches are occasionally amusing, they’re often annoying and rarely dangerous. The culprit behind this chaos? Jamming devices in Israel or Syria that manipulate the Global Positioning System (GPS).
For pilots responsible for airplanes, however, the issue becomes unsettling.
Experts Differentiate Between Jamming and Spoofing
Jamming involves emitting strong signals on GPS frequencies, overpowering the receivers in planes and on the ground, rendering them non-functional. "We've known about this for years during approaches to Seoul," says Niklas Ahrens from the Cockpit Pilots’ Association. Seoul's airport is located 35 kilometers from North Korea, and “you can be fairly certain that GPS won't be available during the approach."
Ahrens, who regularly co-pilots an Airbus 330 or 340 for a major airline, relies on ground-based radio beacons and air traffic controllers using radar to guide the plane when GPS fails.
GPS spoofing, however, is more sophisticated. Spoofing devices trick the receiver into believing it's in a different location.
In the airspace over Syria, Lebanon, Israel, and Cyprus, the displayed aircraft position sometimes suddenly shifts to Beirut, and cockpit instruments show the plane's speed dropping to zero. “This is easily identifiable as manipulation,” says Ahrens. Near Belarus and Russia, however, spoofing often simulates a false, moving position, which onboard computers don’t immediately recognize as fake.
“The workload increases because we constantly have to question whether the displayed position is still plausible,” Ahrens explains.
GPS Disruptions and Their Broader Impacts
Warring factions jam GPS signals to confuse enemy drones and aircraft. In 2020, U.S. researchers identified a jammer on a Russian-operated airbase on the Syrian coast. With ongoing wars in Ukraine and Gaza, these disruptions have intensified, impacting numerous flights between Europe and Asia.
Since Russian airspace is closed to many airlines, they now take detours over the southern Black Sea, putting them within range of jammers. The resulting disorientation affects both the general public and civil aviation as collateral damage. In Moscow, navigation apps are no longer reliable, and rental bicycles and scooters frequently fail to work.
Data from Open Sky Network
The true extent of GPS manipulation is revealed through data from the Open Sky Network, a grassroots initiative whose members use self-built receivers to analyze airplane positions.
In early November, the group held its global conference at the Center for Applied Aviation Research in Hamburg. Michael Felux, from the Zurich University of Applied Sciences, analyzed data from one million flights across three regions: Poland and the Baltic states, Romania, Bulgaria, Moldova, and Cyprus with the eastern Mediterranean.
Between February and August 2022, GPS navigation was disrupted or failed in approximately 70,000 flights due to jamming. Over the eastern Mediterranean, more than half of the flights were affected.
“Jamming is like someone trying to whisper in your ear while a baby is screaming so loudly that you can’t hear anything,” says Felux, who recently became a father. In this analogy, the jammer is the baby, and the weak satellite signals are the whisper.
Jamming is simple and cheap. Taxi and truck drivers sometimes use USB-connected devices to block vehicle tracking. Ship captains tamper with their positioning transmitters to conceal illegal fishing activities. Disrupting aircraft GPS requires electronics costing just a few hundred euros.
The Rise of Spoofing
Spoofing is becoming increasingly common. "We now see about 1,000 airplanes worldwide affected daily," says Felux's colleague Raphael Monstein, who visualizes the data on spoofing.skai-data-services.com. “If you’re departing from Tel Aviv, you can almost be certain of experiencing spoofing.” Pilot Niklas Ahrens confirms this.
Airplanes don’t crash when satellite navigation fails. Instead, they revert to traditional navigation methods:
Inertial Navigation: Sensors onboard measure movements and accelerations to calculate position.
Radio Navigation: The aircraft triangulates its position by measuring distances to multiple ground stations.
Radar: Air traffic control tracks the plane and communicates steering instructions.
However, the stress levels for cockpit crews and air traffic control rise, even outside war zones. Restarting a GPS receiver after interference isn’t possible mid-flight. Once disrupted, it remains inoperative until landing, even after leaving the jamming zone.
Traditional navigation is less precise than modern GPS, and positional inaccuracies over open water can exceed ten kilometers. This forces planes to maintain larger safety distances, reducing airspace capacity.
Alarm Manipulation Risks
Perhaps the most critical issue is spoofing’s ability to manipulate displayed altitude, potentially triggering false alarms. For example, during a descent, if onboard systems are tricked into believing the aircraft is on a collision course with a mountain, a “Pull-Up” alarm will sound, instructing the crew to climb steeply.
If a false alarm is likely, pilots may ignore the warning. However, the “Pull-Up” alert is the highest-priority alarm, suppressing other critical warnings, such as collision risks with other aircraft. In response, many airlines now automatically disable the “Pull-Up” alarm near conflict zones.
Calls for Action
In August 2024, pilots and air traffic controllers convened in Frankfurt to discuss the situation. They identified GPS spoofing’s impact on cockpit instruments as one of the most pressing security issues, stating that there’s currently “little that can be done to prevent spoofing.”
Niklas Ahrens, representing the Cockpit Pilots’ Association, attended the meeting. He calls for halting the dismantling of ground-based antennas, as has been happening. By 2030, the EU plans for all commercial aircraft to use satellite-based landing systems exclusively, with traditional navigation reserved for emergencies. Pilots disagree. "We need redundancy," says Ahrens. "The systems must become more resilient."
Future Solutions
Efforts to improve satellite navigation resilience are underway. The European GPS alternative, Galileo, has recently tested encryption techniques to make it spoofing-proof. Additionally, new aircraft antennas could be installed to only receive signals from above, where satellites orbit. However, since aviation adopts innovations slowly, it will take years for these technologies to be certified.
Ahrens learned to navigate using paper maps, flipping through them frequently during long-haul flights. Today, pilots use digital maps on iPads. Let’s hope those don’t crash!