A show of motion

As the helicopter clattered away overhead, the good folk of the area were tapping on their keyboards. 

In the local Facebook group, speculation was rife. 

Air-sea rescue? Military? Coastguard? Police?

The consensus seemed to be that it was surveying the railway track. 

To be honest, I didn't care. I was just pleased to get a whirling effect on the blades. Usually the photos I end up with look less like aircraft and more like Airfix kits.