Electricity Substation (UAV LiDAR)
United Kingdom
Capture:Combined UAV LiDAR and photogrammetric capture of a live high-voltage substation: busbars, gantries, transformer bays and the transmission-tower interface.
Our Services
Drone LiDAR survey.
Aerial LiDAR for corridors, vegetation and earthworks.
Fixed-wing and multirotor UAV LiDAR delivering classified point clouds and bare-earth terrain models through vegetation, across corridors, reservoirs, earthworks and upland catchments. Specified to the RICS accuracy bands and reported against independent check points.
Band C–E
RICS accuracy bands specified
70km²
Combined LiDAR envelope, one commission
Multi-return
Ground under canopy
Aerial & Drone LiDAR
In-depth guide: UAV LiDAR for Reservoir Surveys →
What is an aerial LiDAR survey?
An aerial LiDAR survey flies a laser scanner on a UAV over a site and records the time of every returned pulse to build a georeferenced 3D point cloud. Multiple returns from each pulse let the cloud be classified into ground, vegetation, buildings and overhead lines, so the deliverable is a bare-earth terrain model as well as the surface above it.
For the LiDAR versus photogrammetry decision in one table, see our capture methods comparison.
Angell Surveys flies UAV LiDAR from a fixed-wing platform carrying the laser sensor and a metric camera on a single payload, so the LiDAR point cloud and the photogrammetric orthomosaic are captured in the same sortie and share one control network. Multirotor LiDAR covers the smaller and access-constrained sites.
All scan data is adjusted to a documented GNSS ground control network and delivered as classified, georeferenced LAS or LAZ point clouds in the client's required coordinate system, normally OSGB36 and Ordnance Datum Newlyn. We produce bare-earth DTMs, surface models, cross-sections, contours and feature extractions as the brief requires.
Aerial LiDAR is the capture method of choice for hedgerow-bounded farmland, wooded catchments, reservoir embankments and any corridor where photogrammetry alone would model the vegetation top instead of the ground. Classified vegetation returns also feed the canopy height model behind our BNG baseline survey service. For terrestrial laser scanning of buildings and structures, and E57 point cloud delivery, see our point cloud and 3D laser scanning survey page.
Ground under canopy
Can a drone survey through vegetation?
Photogrammetry cannot: it models the visible canopy surface, so hedgerows and woodland appear as raised ground. Multi-return LiDAR can, because part of each pulse reaches the ground through gaps in the canopy and is recorded as a separate return. The quality of the bare-earth model therefore depends on canopy density and season, and it is verified against ground check points observed by GNSS.
When we fly
Leaf-off capture between late autumn and early spring gives the highest ground-return density beneath deciduous cover. Where the programme forces a summer flight, we add overlapping passes to lift the number of pulses reaching the ground, and the accuracy report says so.
How we classify
Automated ground filtering is followed by manual editing of the classified point cloud along hedgerows, watercourse banks and woodland edges, where automated routines are most likely to leave vegetation in the ground class or strip real terrain out of it.
How we verify
Independent GNSS check points are observed on open ground and, where access allows, beneath the canopy, then withheld from the strip adjustment. The residuals at those points are reported against the RICS band the deliverable was specified to (RICS, 2014).
Delivered examples: a 70 km² reservoir DCO survey where mature fen hedgerows would have produced an unusable photogrammetric ground model; a wooded upland catchment in Stirlingshire delivered as a sub-50 cm DTM for flood-risk modelling; and a 250 ha solar and BESS site where LiDAR ground returns replaced false hedgerow surfaces in the drainage DTM.
Overhead lines and substations
Which LiDAR settings detect overhead power lines?
A high pulse repetition rate and a sensor that records many returns per pulse. On our transmission corridor and substation work we fly the DJI Zenmuse L3 at a 350 kHz pulse repetition rate, recording up to 16 returns per pulse, so a thin conductor bundle, the gantry beneath it and the ground below are all captured from the same pass and separated in classification.
Sensor and settings
DJI Zenmuse L3 on a multirotor platform, operated at 350 kHz with 16 returns per pulse. The dense point spacing across a conductor at survey ground speed is what makes the line continuous in the cloud rather than a scatter of hits.
Why returns matter
A conductor intercepts only part of each laser footprint. Recording many returns per pulse means the conductor registers as an early return while later returns continue to the crossarm, the vegetation and the ground, so clearances are measured from one consistent dataset.
Classification and clearance
Conductors, towers and gantries are classified to the ASPRS overhead-line and structure classes, with vegetation and ground beneath them. Clearance to ground and to canopy is then reported along the corridor, and the substation compound is delivered as a measurable reality model.
Delivered example: a live high-voltage substation reality model combining UAV LiDAR and photogrammetric capture, listed on our 3D models page. The method is described in our guide to UAV LiDAR for overhead lines and substations.
Capabilities
What we deliver.
From fixed-wing corridor capture to classified bare-earth terrain models and vegetation products.
Fixed-Wing UAV LiDAR
Large-area and corridor capture from a fixed-wing platform carrying LiDAR and a metric camera on one payload. Beyond visual line of sight flight under our CAA Operational Authorisation where the envelope demands it.
Multirotor UAV LiDAR
Slow, low passes over smaller or access-constrained sites, steep faces and structures where repeated angles and point density matter more than coverage rate.
Point Cloud Classification
Automated and manual classification of ground, vegetation, buildings, water, overhead lines and noise. Delivered as fully attributed LAS or LAZ files to ASPRS convention with tile index and metadata.
Bare-Earth DTM & DSM
Terrain and surface models in GeoTIFF or ASCII grid, with contours and break-lines, for drainage design, hydraulic modelling, earthworks calculation and flood-risk assessment.
Canopy Height & Vegetation Products
Canopy height model (DSM minus DTM), vegetation strata and hedgerow extractions for BNG baselines, woodland survey, visual screening and overhead-line clearance assessment.
Corridor Profiles & Feature Extraction
Cross-sections, long-sections and CAD extractions of watercourses, drains, tracks, boundaries and overhead lines in DWG, DXF or GIS layers, plus hillshade and local-relief rasters for archaeology.
Our Process
How we work.
A documented airborne workflow from brief to classified deliverable.
01
Survey Design
Flight lines, altitude and overlap set against the point density and RICS band specified. Ground control layout and RAMS prepared; flown under our CAA Operational Authorisation, including beyond visual line of sight where the envelope demands it.
02
Control & Capture
GNSS ground control and independent check points observed and tied to OS Net. Sorties flown from temporary operating areas close to the envelope, with in-field coverage checks before demobilisation.
03
Strip Adjustment & Classification
Trajectory processing, strip adjustment and calibration against control, noise removal, automated ground filtering and manual classification editing along vegetation edges and watercourses.
04
Delivery
Tiled LAS or LAZ, DTM, DSM and derived products issued with metadata, tile index, strip-adjustment statistics and the check-point accuracy report, in the client-specified coordinate system.
Sector Applications
Calair Burn — Ballimore Restoration
Balquhidder, Stirlingshire, Scotland
Capture:Fixed-wing UAV LiDAR and photogrammetry over a 9.67 km upland catchment; sub-50 cm DTM in OSGB36/OSTN15.
FAQ
Drone LiDAR survey questions.
Angell Surveys is a RICS-regulated practice (Firm 681790) — verify our registration via the RICS Find a Surveyor directory.
What is a drone LiDAR survey?
A drone LiDAR survey (also called an aerial or UAV LiDAR survey) carries a laser scanner on a fixed-wing or multirotor UAV. The scanner fires pulsed laser at the ground and times each return to build a dense, georeferenced point cloud. Because a single pulse can return from the canopy, the understorey and the ground, the point cloud can be classified to give a bare-earth terrain model beneath vegetation as well as the surface model above it. Angell Surveys flies UAV LiDAR for corridors, reservoirs, earthworks, solar and BESS sites and upland catchments, with terrestrial laser scanning handled under our point cloud survey service.
When should I choose aerial LiDAR over UAV photogrammetry?
Choose LiDAR when the deliverable depends on ground levels beneath vegetation, when surfaces are featureless or poorly lit, or when a classified point cloud is the primary output. Photogrammetry models the visible surface only, so hedgerows, woodland and bank-side vegetation produce a false raised ground model. For large open sites with low vegetation and good texture, UAV photogrammetry is faster and cheaper and delivers a colour orthomosaic as well. On most large projects we fly both sensors on one fixed-wing payload and fuse the results.
How accurate is a drone LiDAR topographical survey?
Accuracy is specified to the RICS Measured Surveys of Land, Buildings and Utilities band table (3rd edition, RICS, 2014) rather than a marketing figure. UAV LiDAR topographic deliverables are normally specified to Band D (±10 mm in plan at 1 sigma) or Band E (±25 mm), with Band C (±5 mm) where the brief and the control network support it. Every survey is flown against a GNSS ground control network and independent check points that are withheld from the strip adjustment; the signed accuracy report records the check-point residuals actually achieved.
What deliverables will I receive from an aerial LiDAR survey?
A classified LAS or LAZ point cloud (ground, low, medium and high vegetation, buildings, water and overhead-line classes to ASPRS convention) is the primary deliverable, tiled on the Ordnance Survey grid for large envelopes. From it we derive a bare-earth DTM and a DSM in GeoTIFF or ASCII grid, contours at the requested interval, a canopy height model, cross-sections and corridor profiles, CAD feature extractions in DWG or DXF, and hillshade and local-relief visualisations where archaeology or drainage teams need them. Every survey ships with a strip-adjustment report and check-point residuals.
Fixed-wing or multirotor for LiDAR?
Fixed-wing UAV LiDAR is the right platform above roughly 20 hectares or for linear corridors: longer endurance, stable sensor geometry over multi-kilometre transects and, under our CAA Operational Authorisation, beyond visual line of sight flight. Multirotor LiDAR suits smaller, access-constrained or geometrically complex sites where slow, low passes and repeated angles matter more than coverage rate. Our fixed-wing platform carries the LiDAR sensor and a metric camera on a single payload so both datasets are captured in the same sortie.
Do you also offer terrestrial laser scanning?
Yes, but under a separate service. Static terrestrial laser scanning (TLS) and handheld SLAM scanning for buildings, structures, plant and confined spaces, with E57, LAS and RCP delivery, are described on our point cloud and 3D laser scanning survey page. This page covers airborne capture only.
Are you RICS regulated?
Yes. Angell Surveys is regulated by the Royal Institution of Chartered Surveyors (RICS); verify via our public profile at ricsfirms.com/office/681790/Angell-Surveys-Ltd. All LiDAR work is conducted under the RICS Surveys of Land, Buildings and Utilities professional standard with documented control networks and independent check points.
Work With Us
Bring engineering precision to your next project.
Most scoping responses sent within one business day.
RICS-regulated work, led by Philip M. Angell MRICS.