9/5/24 

AIM 

GPS repeaters, and even some systems onboard the aircraft. In general, these types of unintentional interference 

are localized and intermittent. Of greater and growing concern is the intentional and unauthorized interference 

of GPS signals by persons using “jammers” or  “spoofers” to disrupt air navigation by interfering with the 

reception of valid satellite signals. 

NOTE

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The U.S. government regularly conducts GPS tests, training activities, and exercises that interfere with GPS signals. These 

events are geographically limited, coordinated, scheduled, and advertised via GPS and/or WAAS NOTAMS. Operators of 

GPS aircraft should always check for GPS and/or WAAS NOTAMS for their route of flight. 

c. 

Manufacturers, operators, and air traffic controllers should be aware of the general impacts of GPS jamming 

and/or spoofing, which include, but are not limited to: 

1. 

Inability to use GPS for navigation. 

2. 

Inability to use hybrid GPS inertial systems for navigation. 

3. 

Loss of, or degraded, performance

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based navigation (PBN) capability (e.g., inability to fly required 

navigation performance (RNP) procedures). 

4. 

Unreliable triggering of Terrain Awareness and Warning Systems (TAWS). 

5. 

Inaccurate aircraft position on navigation display (e.g., moving map and electronic flight bag). 

6. 

Loss of, or erroneous, Automatic Dependent Surveillance-Broadcast (ADS

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B) outputs. 

7. 

Unexpected effects when navigating with conventional NAVAIDS (e.g., if the aircraft is spoofed from 

the intended flight path, autotuning will not select the nearby NAVAID). 

8. 

Unanticipated position-dependent flight management system effects (e.g., erroneous insufficient fuel 

indication). 

9. 

Failure or degradation of Air Traffic Management (ATM) infrastructure and its associated systems reliant 

on GPS, resulting in potential airspace infringements and/or route deviations. 

10. 

Failure of, or erroneous aircraft clocks (resulting in inability to log on to Controller-Pilot Data Link 

Communications CPDLC). 

11. 

Erroneous wind and ground speed indications. 

d. 

When flying IFR, pilots should have additional navigation equipment for their intended route to crosscheck 

their position. Routine checks of position against VOR or DME information, for example, could help detect a 

compromised GPS signal. Pilots transitioning to VOR navigation in response to GPS anomalies should refer to 

the Chart Supplement U.S. to identify airports with available conventional approaches associated with the VOR 

Minimum Operational Network (MON) program. (Reference 1

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1

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3f.) 

e. 

Prior to departure, the FAA recommends operators to: 

1. 

Be aware of potential risk locations. 

2. 

Check for any relevant Notices to Air Missions (NOTAMs). 

3. 

Plan fuel contingencies. 

4. 

Plan to use conventional NAVAIDs and appropriate arrival/approach procedures at the destination. 

5. 

Follow the detailed guidance from the respective Original Equipment Manufacturer (OEM). 

f. 

During flight, the FAA recommends operators do the following: 

1. 

Be vigilant for any indication that the aircraft’s GPS is disrupted by reviewing the manufacturer’s 

guidance for that specific aircraft type and avionics equipage. Verify the aircraft position by means of 

conventional NAVAIDs, when available. Indications of jamming and/or spoofing may include: 

(a) 

Changes in actual navigation performance. 

Performance

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Based Navigation (PBN) and Area Navigation (RNAV) 

1

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2

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