GPS spoofing continues to expand and increase, according to international operations and security intelligence organization OpsGroup, which said it has received nearly 50 reports of fake signals impacting operators involving three different types of incidents.
OpsGroup first sounded the alarm on the spoofing incidents in September, citing a dozen reports of aircraft being targeted with fake signals as they flew over Iraq near the Iranian border. In many cases, this led to a complete loss of navigational capability.
In late October, reports flowed in from operations over the eastern Mediterranean, Egypt, and on approach to Amman, Jordan. In these cases, the aircraft showed a false position of being stationary over Tel Aviv Ben Gurion International Airport (LLBG) even though they were as far as 212 nm away from the area.
The latest incidents now involve flights from LLBG that are being led towards Lebanon with spoofed signals.
OpsGroup said this has been a “real-world discovery of a fundamental flaw in avionics design. If a GPS position signal is faked, most aircraft are incapable of detecting the ruse.” Loss of navigation occurs in some cases, while in others the fake signals have led to “subtle, undetected erroneous tracking. In the worst cases, the impact has been severe—complete loss of onboard nav requiring ATC vectors, IRS failure, and unnoticed off-track navigation towards danger areas and hostile airspace.”
OpsGroup further said, “The industry has been slow to come to terms with the issue, leaving flight crews alone to find ways of detecting and mitigating GPS spoofing.”
The operations specialist cited some of the reports, including a Gulfstream G650 that experienced full nav failure on departure from LLBG on October 25. The crew reported, “ATC advised we were off course and provided vectors. Within a few minutes, our estimated position uncertain (EPU) was 99 nm, FMS, IRS, and GPS position were unreliable. The navigation system thought it was 225 nm south of our present position.”
Similarly, a Bombardier Global Express was spoofed on departure from LLBG, receiving a false GPS position showing as overhead in Beirut. OpsGroup noted the crew said, “The controller warned us that we are flying towards a forbidden area.”
Meanwhile, a Boeing 777 in the Cairo FIR had encountered a 30-minute span of spoofing, with a false position showing the aircraft to be over LLBG.
As for the flight crew, the question is how they can identify when this is happening. OpsGroup said crews have experienced a sudden increase in EPU. Spoofing causes a “jump,” OpsGroup said, “hence EPU values have jumped from 0.1 nm to 60 nm, and more than 99 nm in quick order.”
Further, crews may receive an EFIS warning related to navigation, with some going straight to dead reckoning mode. Another clue is a significant change in the aircraft clock UTC—reports have ranged from a couple of hours to as much as 12-hour changes.
OpsGroup advises that if this occurs, crews should deselect GPS inputs as soon as possible to prevent wider navigation failure, switch to conventional navaids, and report the issue to air traffic control.