In today’s increasingly digital and interconnected aviation environment, aircraft depend heavily on satellite navigation systems for accurate positioning, timing, and routing. The Global Positioning System (GPS)—and other Global Navigation Satellite Systems (GNSS) are the foundation of modern air navigation. From en route flight planning to precision approaches, these systems are critical to maintaining the safety, efficiency, and predictability of global air traffic.
However, with this reliance comes vulnerability. One of the most concerning threats to GPS integrity is GPS spoofing—a sophisticated cyber technique that deliberately manipulates GPS signals to mislead navigation systems. In aviation, the consequences of such interference can range from navigational drift and route deviations to disruptions in surveillance systems and increased flight crew workload all of which have an impact on safety.
This blog post explores what GPS spoofing is, why it poses a serious threat to aviation, how it differs from other types of signal interference, and what actions aviation stakeholders can take to identify, respond to, and mitigate its impact.
GPS spoofing occurs when a device transmits counterfeit GNSS signals that mimic those sent by legitimate satellites. These false signals are carefully crafted to deceive GPS receivers into believing that the aircraft—or any receiving device—is located somewhere else. This manipulation can gradually or suddenly shift the receiver’s calculated position, leading to erroneous navigation data being displayed to pilots or recorded by automated systems.
Spoofing is significantly more dangerous than GPS jamming. While jamming causes a loss of satellite signal reception, alerting pilots and systems to an issue, spoofing provides a seemingly valid but false position. This deceptive nature means that aircraft may continue to operate as though everything is normal—until anomalies become obvious, or the aircraft begins to behave unpredictably on navigation displays or ATC surveillance systems.
Unlike cyberattacks targeting onboard IT networks, GPS spoofing targets the aircraft’s external communication environment, making it extremely difficult to detect until discrepancies arise. For aircraft flying over oceanic or remote regions, where ground-based navigation aids are sparse, this vulnerability becomes even more pronounced.
The rise in GPS spoofing incidents has elevated concern across the aviation industry, particularly among airlines, charter operators, business aviation, and flight operations service providers. Over the last five years, documented spoofing events have increased in both frequency and sophistication, particularly near conflict-prone regions or areas of heightened geopolitical tension.
These spoofing events often occur without warning, and unlike weather phenomena or airspace restrictions. A single spoofing attack can affect multiple aircraft within a region simultaneously, leading to widespread navigational inconsistencies, loss of GNSS approach capability, and potential airspace infringements if left unchecked.
Furthermore, Automatic Dependent Surveillance–Broadcast (ADS-B) systems rely entirely on GNSS positioning to broadcast aircraft location to air traffic controllers and other nearby aircraft. When spoofed data corrupts these position reports, it can result in inaccurate surveillance, false proximity alerts, and a breakdown of air traffic situational awareness—particularly in busy or uncontrolled airspace.
For pilots, GPS spoofing not only compromises navigation but increases workload sometimes during critical phases of flight. Requirements to manually cross-check conflicting data, request position verification from ATC, or reprogram navigation equipment can divert attention from other essential flight tasks, increasing the workload.
Spoofing can subtly infiltrate an aircraft’s navigation logic, influencing multiple interconnected systems. In typical cases, an aircraft may suddenly display position drift, show incorrect distances or bearings to waypoints, or switch to dead reckoning (DR) mode as the system attempts to cope with inconsistent inputs. These symptoms might initially appear as minor anomalies, but their impact can escalate quickly.
Most modern aircraft rely on GNSS inputs to guide flight routes entered in the FMS. When a spoofing attack occurs, the FMS may falsely interpret the aircraft as being off-route, prompting unexpected course corrections, incorrect waypoint sequencing, or the activation of incorrect flight legs. In aircraft with limited fallback to inertial navigation, this could result in serious route deviations, especially during long-haul or oceanic sectors.
Spoofed signals can corrupt vertical navigation (VNAV) profiles and disrupt performance-based navigation (PBN) procedures such as Required Navigation Performance (RNP) approaches or Localizer Performance with Vertical Guidance (LPV). As these procedures require precise positional data, spoofing may cause unstable approaches, false glideslope data, or complete loss of guidance, forcing a go-around or diversion. It is general industry guidance that crews whose aircraft have encountered spoofing en route, do not fly an RNP approach.
TAWS and Enhanced Ground Proximity Warning Systems (EGPWS) are safety-critical systems that rely on accurate aircraft position and elevation data. If GPS spoofing results in incorrect altitude or location information, the system may issue false terrain warnings—or worse, fail to trigger valid alerts when terrain proximity becomes a threat.
Spoofing also affects ADS-B OUT, which relies on GNSS to provide aircraft position to external receivers. A spoofed position can result in ATC seeing the aircraft in the wrong location or other aircraft receiving incorrect collision avoidance alerts. The Traffic Collision Avoidance System (TCAS) could be misled by incorrect transponder broadcasts, creating false conflict alerts and reducing confidence in surveillance reliability.
Spoofing incidents have been reported in multiple regions around the world, often near conflict zones or politically sensitive airspace. These include:
While Ireland and Western Europe are not frequent targets of spoofing, incidents of spoofing have occurred at times.
Operators should establish clear standard operating procedures (SOPs) to address GNSS anomalies. These might include fallback navigation techniques using VOR/DME, or even manual time-speed-distance calculations when necessary. Operators and crew should always refer to their own company in-house SOPs.
Flight planning tools should incorporate GNSS threat intelligence. Briefings should identify known spoofing zones and assess the impact on planned approaches, contingency airports, and alternate nav sources.
Aircraft equipped with multi-sensor navigation systems that integrate GPS with INS and DME inputs are more resistant to spoofing. These systems can cross-check data sources and alert crews when a conflict arises.
Authorities such as ICAO, EASA, and FAA provide guidance on GPS spoofing detection and response. Pilots are encouraged to report spoofing incidents to aviation authorities and manufacturers to support ongoing mitigation efforts. Ops Group also produced a report and recommended guidance which was the result of an industry wide focus and research group of which Six West was part.
Sinéad is a Six West Aviation marketing manager and business development specialist. She is responsible for managing our communications, social media and event outreach strategy.
November 6, 2025
