It was the last minute of the flight, just before landing at Beirut International Airport, when the Airbus 320's ground proximity warning system (the system that warns pilots if their plane is about to hit a mountain or other obstacle) screamed: “Ground! Up! Up!”
Fadi Ramadan, the 37-year-old driver, resorted to the emergency protocol that was drilled into him every six months for the past 15 years of his racing career.
“At this point, it's a matter of muscle memory. When we received this warning, we immediately throttled to the limit and used the full control lever to bring the plane to a safe altitude,” said Ramadan, a former employee of Lebanon's flag carrier, Middle East Airlines.
He was about to do just that, but as he looked around the cockpit, he knew something was wrong with the plane's Global Positioning System (GPS). They weren't near the mountains overlooking the airport, and he could see the runway right in front of him. And the plane's instrument landing system, which relies on radio navigation, showed they were in the right place.
“Don’t pay attention,” he told his co-pilot, and landed the plane with the alarm ringing all the way to the boarding gate.
Ramadan and other pilots flying over Lebanon that October day were victims of an attack known as “GPS spoofing,” which sends spoofed GPS signals to receivers, overwhelming the legitimate but weaker signal from navigation satellites and making the receivers think they are in a different location.
This was followed by other spoofing attacks affecting parts of Lebanon, Israel, Syria, Jordan, Egypt, Turkey and Cyprus, part of a spate of signal disruptions that are becoming commonplace in the Middle East. In a recent 72-hour period, for example, researchers at SkAI Data Services, using information from the OpenSky network, detected nearly 2,000 spoofed aircraft.
The attacks differ from the more common GPS jamming, which simply interferes with the signal between the satellite and the receiver.
Spoofing can “simulate the entire GPS satellite constellation to trick the recipient into believing they are in a different position,” said Benoit Figuet, co-founder of SkAI.
“It’s affecting a huge area, which means it requires energy,” Figuet said. “So it’s probably a military activity. It’s not just some hobbyist having fun in the garage.”
Analyzing measurements from low-Earth orbit satellites over the eastern Mediterranean, researchers at the University of Texas at Austin's Radio Navigation Laboratory traced the spoofing to an airbase in northern Israel.
In the weeks following the Hamas attack on October 7, Israel worked to counter missile attacks by Hamas and its Lebanese ally Hezbollah. The latter possesses an arsenal of GPS-guided munitions supplied by Iran, including drones.
The Israeli military confirmed in October that it was proactively disrupting navigation systems “for various operational needs,” adding that location-based apps on people’s phones would be affected.
In April, Israeli military spokesman Rear Admiral Daniel Hagari also acknowledged that the military intervention was aimed at “neutralizing threats.”
“We are aware that these disruptions cause inconvenience, but it is a vital and necessary tool in our defensive capabilities,” Hagari said at a news conference.
These inconveniences have affected people far beyond Israel's borders, affecting not only aviation but also maritime transport.
“This is an attempt to use the most powerful form of electronic warfare and GPS-based navigation,” said Todd Humphreys, a professor of aerospace engineering at the University of Texas at Austin. “However, they can’t limit the spoofing to Israel’s borders because they need to saturate the receivers that are designed to resist that spoofing.”
That means the signal interference is affecting a much wider area, Humphreys said. “They need to be much more powerful than traditional GPS to overcome a GPS receiver, so the signals are being felt as far away as Cyprus.”
Israel's spoofing has also wreaked havoc on GPS-dependent consumer software such as Google Maps, food delivery and dating apps. Baffled users across the region say their smartphones are suddenly telling them they are somewhere at Beirut International Airport or in the Egyptian capital, Cairo.
“It affects 80% of our drivers and hinders our work. We receive constant complaints,” said Marwan Fayyad, head of Lebanon’s taxi drivers’ union. Drivers have had to reduce the number of trips they can make because of the extra time required.
After the impersonations began in October, Fayyad met with several government officials, but to no avail.
“The government can't do anything. All we can do is wait for this to end,” Fayyad said.
In March, Lebanon’s foreign ministry filed a complaint with the UN Security Council over what it described as Israel’s “reckless” disruption of signals since the start of the Gaza war, saying it was an attack on Lebanon’s sovereignty that has “dangerous consequences for the security of civil aviation as well as the lives of thousands of civilian passengers every day.”
The effect on air traffic is what aviation experts are most concerned about, with pilots being ordered to turn off the plane’s GPS receiver and rely on other means of navigation. That can work, but the spoofing has been so powerful that in some cases it affects the plane’s inertial reference systems (which use sensors to extrapolate from a last known GPS position), corrupting onboard position calculations and forcing pilots to call air traffic control for help. That could quickly become an overwhelming situation for already stressed air traffic controllers.
An alternative solution may be to rely on other global satellite navigation systems. GPS is owned by the US government and operated by the US Space Force, but there is also Russia's GLONASS, China's BeiDou and the European Union's Galileo system.
But only GPS is used for air navigation, and these systems are also susceptible to falsification.
Potentially more dangerous is the effect of GPS disruptions on an aircraft's avionics suite, Humphreys said.
“There is no doubt that safety has been reduced on flights in the Eastern Mediterranean because airlines are ordering their pilots to turn off GPS, along with automatic collision avoidance and terrain warning systems,” he said.
“They were put there for a reason, so the danger is that we are normalizing the aberration.”
Ramadan, the airline pilot, said spoofing had been especially damaging to airlines unfamiliar with the region; he heard pilots say on multiple occasions over the radio that they were executing procedures to avoid the terrain.
“But the worst thing is that pilots are getting used to the collision warning,” Ramadan said. “Now they question it and are slow to solve a very high-risk problem when they are supposed to react very quickly. In real-life conditions, this could prove catastrophic.”
