Where would HMS Belfast hit right now?

Belfast's forward turrets are fixed, pointed at the London Gateway services 18.7 km away. This page works out where a shell fired from that laying would land in today's weather.

A point-mass ballistics engine flies the shell, with drag tuned to Belfast's own range tables. Live wind at every altitude, air density, Earth curvature, Coriolis, spin drift and the Thames tide all bend the arc. The output is one likely impact point and a Circular Error Probable: how tightly the shells would group, given gun scatter and forecast uncertainty.

The aim is assumed and several inputs are estimates, but the physics matches the range tables to within ~2%. Numbers below the map.

The place name comes from OpenStreetMap, and a Claude vision model reads the rendered impact map to add the casual one-liner. Both are baked into the page every 30 minutes by a scheduled job, not computed per visitor.