Aerial survey of land and sites around Liskeard

This part of Cornwall carries a good deal of renewable generation, and wind turbines are a genuine planning consideration rather than a scenic detail. They are tall, they move, and the air downwind of a working turbine is disturbed in a way that matters to a light aircraft holding a survey line.

So a survey on ground with turbines on it is planned around them: flight lines set to keep clear, heights chosen deliberately, and the operator spoken to where the machines are close to the working area. None of that is difficult, but it has to happen before the visit rather than being improvised on arrival.

Arrays are common on the open ground here, and from above an array is a straightforward subject: rows, tracks, inverter stations, fencing, drainage and the state of the grass and scrub growing through and under the panels.

What a daylight survey covers is the site. What it does not cover is the electrical condition of the panels, which shows in thermal rather than in visible light and needs a different camera on a different flight. There is a separate site in this group set up for that, and pointing at it is more use than pretending one flight does both.

Bodmin Moor rises to the north, and the ground below it carries granite workings, old and current, along with the remains of a long mining history. Rough ground, quarry faces, spoil and scrub, most of it awkward to walk and straightforward to fly.

The limits are the ones this site repeats because they matter: gorse and scrub hide surface detail, particularly in late summer; a vertical face needs oblique passes rather than a downward grid; and a volume needs an agreed base surface before anybody flies.

The valleys east of the town are steep and wooded, and they concentrate every constraint at once: height change across a short distance, canopy hiding the ground beneath it, and shade for much of a short winter day.

A survey there is planned in sections, flown when the light is at its best rather than when the diary is free, and reported with a clear statement of which parts of the parcel the model can be trusted on and which it cannot.

Rainfall here is well above average and the ground is high and open, so driving rain from the south-west is more or less the winter default. Wind, not rain, usually decides whether a flight happens, because the rain passes and the wind does not.

Repeat sites cope with this well: the plan is on file, so a visit can be flown at short notice when a decent morning arrives. One-off bookings are made against a target week rather than a fixed day.

A branch line runs south from here down a wooded valley, and railways of any kind are corridor jobs rather than block jobs: a strip flown along the alignment, wide enough to hold the cuttings, embankments and drainage either side, priced by length.

Vegetation encroaching on a line, the condition of a cutting after heavy rain and access for maintenance are the usual reasons for asking. Anything involving an operating railway needs the operator's agreement before a date goes in the diary, and that conversation happens first.