MOD Electronic Warfare Exercise May Disrupt GPS in Devon and Cornwall

Residents in Devon and Cornwall are being warned of possible disruptions to satellite navigation systems due to a Ministry of Defence (MOD) electronic warfare exercise.

The exercise, named “Rock Lobster,” is taking place at the MOD’s Sennybridge training area in Wales. Although the site is nearly 200 miles away, the effects could reach parts of the South West, including Devon and Cornwall.

The operation involves radio frequency jamming aimed at interfering with Global Navigation Satellite Systems (GNSS), such as GPS, and signals used to control drones. The jamming is active daily from 8am to 5pm until Friday, June 20, within a 5-kilometre radius of Sennybridge.

According to the Civil Aviation Authority (CAA), the interference could affect navigation for aircraft, vehicles, and drones, with disruptions possible up to 40,000 feet—an altitude used by many commercial airliners. The affected area spans much of south and mid-Wales and may extend as far south as Devon and Cornwall.

Aircraft operators are reminded to ensure they have backup navigation systems and be ready to use traditional methods such as radio beacons, map reading, and dead reckoning. Pilots flying under Visual Flight Rules (VFR) should take extra precautions and plan accordingly.

Air Navigation Service Providers have been briefed and are prepared to assist aircraft encountering degraded GPS signals.

The CAA also advises local residents and drone users to be aware that some electronic devices may temporarily experience disruptions.

For more information or urgent concerns during the exercise, contact Sennybridge Operations at 01874 635599 or the trial manager at 01980 951989.