The whole runway surface, at a resolution you can measure from
Pavement fails slowly and then all at once. A low serpentine pass images the full width of a runway or taxiway at a known ground resolution, so cracks, spalls, joint breakdown and debris are found and located while they are still maintenance rather than a closure.
Coverage that is calculated, not estimated
A pavement scan is only worth as much as its worst-covered strip. So the pass is derived from the camera, not from a guess.
The run count comes out of the optics
From the scan altitude, the gimbal angle and your camera's field of view, the per-image ground footprint is computed, and from that the number of parallel runs needed to cover the surface width at the overlap you asked for. Forward spacing between frames comes out of the same footprint. The flight speed is then checked against the camera frame rate using that spacing, so a high-overlap scan can never be flown too fast to actually capture every frame it plans. Altitude follows the terrain, so the commanded height above the pavement holds even where the surface falls away.
Scan the part you care about
You are not limited to whole surfaces. The along-track window can be capped or trimmed at both ends and measured from either runway end, so re-checking the first 600 metres off one threshold is one setting. The band across the surface can be narrowed to a single side, which is how a shoulder or one half of a wide apron gets scanned without flying the rest. Runs can be laid along the surface or across it. This pass also satisfies the visual aids requirement to overfly the full length of the runway at low level, so the pavement scan and the pattern and obstruction check come off one sortie.
What the report answers
Every finding located on the surface, so the next survey compares against this one rather than starting over.
Longitudinal, transverse and block cracking located along the surface, with extent and severity recorded per crack.
Surface loss at joints, edges and slab corners, including where aggregate has begun to work loose.
Sealant loss, joint spalling and faulting between slabs, run along the full joint rather than sampled.
Loose material on the pavement at capture time, with position, so it can be cleared before it is ingested.
Rubber deposits in the touchdown zone and the condition and contrast of painted markings.
Depressions and ponding evidence where water is standing rather than running off.
The low-level pass along the full runway also confirms visual contact with the runway elements is not obstructed.
Each finding carries a surveyed position, so change between visits is measured rather than remembered.
Built for both sides of the runway
Airports get compliant inspections without closures. Certified drone operators get a new service line through the partner program.