Drone search and rescue cover in Sidmouth

The town grew up where the River Sid reaches the sea, squeezed between two steep hills that channel wind off the water and push it up the valley toward the esplanade. That funnelling effect makes conditions here more turbulent and gustier than the open coast on either side, and it is a factor the pilot has to read and plan around before every flight, not simply check once at the start of the day and forget about.

Salt reaches the esplanade hard on a south-westerly, and the same wind that batters the seafront gets squeezed and accelerated as it climbs the hillsides on either flank of the town. That is often where the more demanding flying around Sidmouth happens, well above the shelter of the valley floor.

Peak Hill to the west and Salcombe Hill to the east both carry coast path routes along the top of the Jurassic Coast cliffs, ground that is slow going and can be dangerous to search on foot in poor visibility or failing light. A walker overdue on either path is one of the more common scenarios here, and a single flight can run the clifftop path and the ground below it without anyone having to walk that edge themselves.

The visual camera picks out detail on the path and the open grass above the cliff line during daylight, while the thermal camera comes into its own as light fades, when a foot search over exposed, uneven cliff-top ground becomes slower and considerably riskier for whoever is doing it.

Sidmouth's Regency esplanade also draws large crowds through the summer months, and a busy seafront is its own kind of search ground: a lost child or an overdue swimmer is easier to place quickly from a wide aerial view of the beach and promenade than from a single vantage point at ground level, where a crowd itself blocks the sightline a searcher would otherwise rely on.

Sidmouth's compact centre and esplanade give a workable launch point close to both hills, so a flight can be climbing toward Peak Hill or Salcombe Hill within a few minutes of arriving. That is useful when a search coordinator needs high ground checked before committing a foot team to a steep, time-consuming climb on a route that may turn out to be clear.

As with any search near a cliff edge, the aim is to answer where someone is without anyone else having to go near the drop to find out, and to feed that answer back to whoever is running the search on the ground, whether that is the police or another coordinator.