It was the last minute of the flight, just before touchdown at Beirut’s international airport, when the Airbus 320’s ground proximity warning — the system that warns pilots if their aircraft is about to hit a mountain or other obstacle — squawked, “Terrain! Pull up! Pull up!”
Fadi Ramadan, the 37-year-old pilot, fell back on the emergency protocol drilled into him every six months for the last 15 years of his flying career.
“It’s muscle memory at this point. Whenever we get this warning, we immediately go full power and full back stick to get the plane to a safe altitude,” said Ramadan, a former employee of Lebanon’s flagship carrier Middle East Airlines.
He was about to do just that. But looking out the cockpit, he knew something was wrong with the plane’s Global Positioning System, or GPS. They were nowhere 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.
“Disregard,” he told his co-pilot, and landed the plane with the alarm blaring all the way to the gate.
Ramadan and other pilots flying over Lebanon that October day were victims of an attack known as “GPS spoofing,” which sends counterfeit GPS signals to receivers, overwhelming the legitimate but weaker signal from navigation satellites and making receivers think they’re in a different location.
Other spoofing attacks have followed, affecting areas in Lebanon, Israel, Syria, Jordan, Egypt, Turkey and Cyprus — part of a deluge of signal disruptions that are becoming a regular occurrence over the Middle East. In a recent 72-hour period, for example, researchers from SkAI Data Services, using information from the OpenSky Network, detected almost 2,000 spoofed planes.
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 constellation of GPS satellites to trick the receiver into believing they’re in a different position,” said Benoit Figuet, SkAI’s co-founder.
“It’s affecting a huge area, which means you need power,” Figuet said. “So this is probably military activity. It’s not a hobbyist in the garage just having fun.”
By analyzing measurements of low-Earth orbit satellites over the eastern Mediterranean, researchers with the University of Texas at Austin’s radio-navigation lab tracked the spoofing to an air base in northern Israel.
In the weeks after Hamas’ Oct. 7 attack, Israel worked to counter missile strikes from Hamas and its Lebanese ally Hezbollah. The latter possesses an Iran-supplied arsenal of GPS-guided munitions, including drones.
The Israeli army confirmed in October that it was disrupting navigation systems “in a proactive manner for various operational needs,” adding that location-based applications on people’s phones would be affected.
In April, Israeli military spokesman Rear Adm. Daniel Hagari also acknowledged the military’s disruption was meant to “neutralize threats.”
“We are aware that these disruptions cause inconveniences, but it is a vital and necessary tool in our defensive capabilities,” Hagari said in a news conference.
Those inconveniences have hit people far beyond Israel’s borders, affecting not only aviation but also maritime shipping.
“This is an attempt to use the most potent form of GPS electronic and navigational warfare,” said Todd Humphreys, an aerospace engineering professor at the University of Texas at Austin. “Yet they cannot contain the spoofing to just the borders of Israel, because they need it to overwhelm receivers that are designed to resist such spoofing.”
That means the signal interference is affecting a much wider area, Humphreys said. “They need to have many times the traditional power to overcome a GPS receiver, so the signals are being felt all the way out to Cyprus.”
Israel’s spoofing has also wreaked havoc on GPS-reliant consumer programs, such as Google Maps, food delivery and dating apps. Bewildered users across the region say their smartphones are suddenly telling them they are somewhere in Beirut’s international airport or in the Egyptian capital, Cairo.
“It’s affecting 80% of our drivers and obstructing our work — we’re getting constant complaints,” said Marwan Fayyad, head of Lebanon’s taxi drivers union. Drivers have had to cut back on the number of trips they can do because of the extra time required to navigate.
After the spoofing began in October, Fayyad met with several government officials, but to no avail.
“The government isn’t able to do anything. All we can do is wait for this to end,” Fayyad said.
In March, Lebanon’s foreign ministry lodged a complaint with the U.N. 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 on the safety of civil aviation, as well as on the lives of thousands of civilian passengers every day.”
The effect on air traffic worries aviation experts the most, as pilots are instructed to shut off a plane’s GPS receiver and rely on other means of navigation. That may work, but the spoofing has been so powerful that in some instances it affects a plane’s inertial reference systems (which use sensors to extrapolate from a last known GPS position), corrupting any onboard position calculations and forcing pilots to ask air traffic control for assistance. That could quickly become overwhelming for already stressed air traffic controllers.
One workaround may be to rely on other global navigation satellite systems. GPS is owned by the U.S. government and is run by the U.S. Space Force, but there’s also Russia’s GLONASS, China’s BeiDou, and the European Union’s system, Galileo.
But only GPS is used for airplane navigation, and those systems are also susceptible to spoofing.
Potentially more dangerous is the effect of GPS disruptions on a plane’s avionics suite, Humphreys said.
“There’s no question that safety has been reduced in flights in the eastern Mediterranean because airlines are instructing their pilots to shut off GPS, along with automatic collision avoidance and terrain warning systems,” he said.
“They’ve been put in for a reason, so the danger is that we’re normalizing aberration.”
Ramadan, the airline pilot, said the spoofing had been especially disruptive for airlines not familiar with the region; he’s heard on multiple occasions pilots coming over the radio to say they’re running terrain avoidance procedures.
“But what’s worse is that pilots are getting used to the collision alert,” Ramadan said. “Now they question it and take time to troubleshoot a very very high risk alert when they’re supposed to react very quickly. In real-life conditions, this could prove catastrophic.”
