GPS Spoofing Risks Grow as US and Europe Revise Aviation Guidelines

Aviation Authorities Issue Revised Guidance on GNSS Interference

A significant revision to official guidance on GPS and Global Navigation Satellite System (GNSS) interference has been published by U.S. and European aviation authorities. This update responds to a documented expansion of jamming and spoofing activity across multiple global regions, posing a direct challenge to the integrity of airborne navigation systems. The Federal Aviation Administration (FAA) released Version 1.1 of its "GPS and Global Navigation Satellite System Interference Resource Guide" in April 2026, a substantive update incorporating analysis from industry rulemaking committees. Concurrently, EUROCONTROL maintains its established guidelines for interference testing and mitigation. For flight departments and operators, these documents represent the current standard for recognizing, reporting, and managing in-flight GNSS disruptions. FlySafe analysis shows that adherence to this updated guidance is now a critical component of operational risk management in affected airspace.

Affected Airspace and Operational Impact

Airspace status: The threat environment for GNSS interference is no longer confined to isolated regions. According to the FAA's updated resource guide, interference is occurring across a widening range of high-risk airspace. Specifically cited regions include the airspace over the eastern Mediterranean, the Black Sea, the Russia-Baltic region, the India-Pakistan border, Iraq and Iran, and the Korean peninsula. This activity is dynamic and unpredictable, as highlighted in a white paper on mitigating risks, which describes GPS interference as "dynamic, widespread, and unpredictable" with impacts ranging from operational inefficiencies to safety risks.

Affected routes: Any flight route traversing the Flight Information Regions (FIRs) associated with the above geographic areas is subject to potential disruption. The interference does not discriminate between airline, cargo, or business aviation traffic. Richard Boll, chair of NBAA’s Airspace and Flight Technologies Subcommittee, emphasized the expanding nature of the threat, warning that "US and European operators should not assume they are insulated," and noted that the United States has experienced cases of widespread GPS interference. This underscores that the issue is of global concern to the aviation community.

Recognizing and Responding to Spoofing Events

Pilot awareness of the indications of spoofing is the first line of defense. The FAA guide provides a specific list of cockpit indicators that should trigger suspicion of GNSS spoofing. These include, but are not limited to:

• Disagreement in navigation position between GNSS and other sources (e.g., IRS).
• Abnormal differences between indicated Ground Speed and True Airspeed.
• Uncommanded shifts in displayed time and date.
• Spurious Terrain Awareness and Warning System (TAWS) alerts.
• A sudden, unexplained deviation of the GNSS-based navigation position.

When such indications occur, the prescribed response is immediate suspicion of interference and activation of mitigation procedures. The foundational step, as outlined in EUROCONTROL's guidelines for interference scenarios, is for the pilot to revert to primary means of navigation: "the pilot should revert to dead reckoning or ask the ATCO for vectoring." This prioritizes maintaining situational awareness and flight path integrity through traditional skills and ATC support.

Updated Mitigation Strategies and Pilot Procedures

The revised FAA guide moves beyond basic recognition to offer detailed mitigation strategies and updated pilot procedures. The guidance is intended for both U.S. and foreign operators conducting operations in U.S. sovereign airspace, and its principles are applicable globally. Key recommendations include:

Pre-flight Planning:

• Review NOTAMs: Thoroughly review all relevant NOTAMs for destination, alternate, and en-route airspace regarding GNSS interference (e.g., Jamming, Spoofing).
• Escape and Diversion Planning: The FAA specifically advises operators to "Review any escape routes for an emergency descent... and diversion airport options" in the context of known GNSS interference areas. This elevates contingency planning from a routine task to a critical safety action.
• OEM Coordination: Operators are directed to coordinate with their aircraft Original Equipment Manufacturer (OEM) to obtain and understand any proprietary "jamming/spoofing procedures and checklists" developed for their specific aircraft and avionics suite.

In-flight Response:

1. Cross-Verification: Immediately cross-check all navigation information using independent sources: inertial reference systems (IRS), VOR/DME, and ATC radar vectors.
2. Communication: Notify Air Traffic Control of the suspected interference and any resulting navigational uncertainty. Request conventional navigation assistance.
3. Procedure Execution: Follow validated OEM checklists to isolate or mitigate the effects on aircraft systems, which may include reverting to alternate navigation modes.
4. Official Reporting: Report the event through the appropriate channels. For GPS users globally, this includes the U.S. Department of Homeland Security's Navigation Center (NAVCEN). For Galileo users, the European GNSS Service Centre (GSC) is the designated point of contact, as noted in the EUROCONTROL guidelines.

The Role of Technology and Industry Collaboration

Addressing this systemic risk requires collaboration between regulators, operators, and technology providers. The FAA's guide update was developed with input from the Performance-Based Operations Rulemaking Committee (PARC) GPS/GNSS Disruption Action Team, demonstrating a concerted industry-regulator effort. Furthermore, technological solutions are emerging in the market. For instance, services like GPSwise are designed to monitor GPS interference "as they evolve in real-time" for Air Navigation Service Providers and aircraft operators, representing a tool for enhanced situational awareness.

The core recommendation for airlines and flight departments is to institutionalize this new guidance. This involves:

• Integrating the updated FAA and EUROCONTROL procedures into company Standard Operating Procedures (SOPs).
• Updating simulator and recurrent training curricula to include realistic spoofing recognition and response scenarios.
• Ensuring all pilots are briefed on the specific indicators and the global airspace where interference is most prevalent.
• Establishing clear protocols for post-event reporting to contribute to the collective awareness of the threat landscape.

Key Takeaway: The revision of official guidance by the FAA and EUROCONTROL is a direct response to the increased prevalence and geographic spread of GNSS interference. For operational personnel, these documents are not merely advisory but constitute essential reading. The prescribed mitigation steps—vigilant pre-flight planning, recognition of cockpit indicators, immediate reversion to primary navigation, and systematic reporting—form a critical defense against a threat that compromises a fundamental element of modern aviation infrastructure.

FlySafe Analysis Disclaimer: This bulletin is based exclusively on publicly available data and guidance documents published by the FAA, EUROCONTROL, and associated aviation bodies. FlySafe Research does not possess, access, or utilize any classified or non-public information. The analysis presented is for situational awareness and professional consideration only.

For continuous monitoring of airspace risk factors, including analysis of NOTAMs and operational advisories related to navigation integrity, visit FlySafe Research.