Exercise "Strongbow" at the Caerphilly Railway Tunnel in 2005, was the Gwent RAYNET Group's first foray into tunnel communications. We joined members of the South Glamorgan RAYNET Group for this exercise which was based solely on testing the ability of all participants to communicate with one of their staff aboard a train, which travelled from Lisvane Station (Cardiff), through the Caerphilly Tunnel, before returning to Lisvane. South Wales Fire Service also made use of their "Unimog" Road/Rail vehicle, testing both communications within the tunnel and the vehicle's accessibility.

At this exercise, RAYNET were the only participants who managed to maintain communications with an operator on the train. RAYNET members were located at Lisvane Station and on a road overbridge at Caerphilly. Whilst neither station maintained full comms. with the operator on the train, by the time "one end" lost comms., the other was in communication with the train operator, with an "overlap" in comms. through the tunnel. Additionally, RAYNET operators outside the tunnel were in full communication with each other and were able to continue the test "messages".

RAYNET members and emergency services personnel gather at Lisvane Station (Cardiff) prior to the start of Exercise "Strongbow". © GW8JOY 2005

Steve (GW6CUR) and Roy (GW1XZI) of South Glamorgan RAYNET with their radio station at the old Cefn Onn station, with the tunnel portal in the background. © GW8JOY 2005

View from the old Cefn Onn station back toward Lisvane Station, with the Unimog in the background, just after being railed. © GW8JOY 2005

The Unimog passing the old Cefn Onn station heading for Caerphilly Tunnel. The tripod-mounted aerial is a 23cm Yagi, pointing at the tunnel portal. © GW8JOY 2005