GA1409 - Intentional GPS jamming/spoofing
Initial Report
AIC P 141/2025 details intentional GPS jamming and spoofing taking place at Sennybridge. The document details effects up to 80nm from the jamming/spoofing source. GPS is the primary means of navigation for most GA flights, with pilots being advised by the CAA to use it, in conjunction with moving map displays, to prevent airspace infringements etc. Close to Sennybridge was BCN VOR, but this has now been removed, so there is no VOR to use as an alternative navigational aid. Close to Sennybridge is Cardiff airspace, they have an active NOTAM stating they will not offer a service to GA aircraft. Radar assistance is therefore not readily available to aircraft uncertain of their position.
Why is intentional jamming/spoofing of GPS permitted in the above circumstances? It is inherently unsafe.
CHIRP Comment
Very topical report as use of GPS is increasingly used for navigation by very many GA users, and for understandable reasons when all things are going well! Moreover, the CAA continues to encourage the use by GA pilots of Moving Map Devices (MMD) as one of the measures to reduce the incidence of airspace infringements. Since regulatory changes were made in October 2025 the use of MMD can be included in PPL training and may now, for example, form part of PPL skill tests. However, not least because of the vulnerability of the system to interference (planned or otherwise), CAA training and test syllabi still require good knowledge of and demonstrated skill in using conventional navigation techniques.
Our approach to reliance on GNSS in aviation has always been tempered by the fact that the signal in space remains vulnerable to interference such as jamming and spoofing. (Whether periods of military training such as this are promulgated or not). This area within 80nm of Sennybridge ranges is clearly a piece of airspace where GPS navigation is particularly vulnerable to disruption during the scheduled periods of these jamming activities. The reporter therefore provides a timely reminder to ensure that the effective use of other navigation aids and aviation charts for VFR navigation must remain a core part of every GA pilot’s skill set.
Key Issues relating to this report
Human Factors Considerations
The following ‘Dirty Dozen’ and Human Factors were a key part of the CHIRP discussions about this report.
Positive HF elements:
- Safety/learning culture – proactive self-reporting of a flight safety issue for wider awareness
Be wary of:
- Complacency – over dependency on GPS provided navigation in areas and at times when satellite signal/service is unreliable