SenSat, a UK provider of photogrammetry for construction and infrastructure projects, has test flown an autonomous c-drone 12km beyond visual line of sight (BVLOS) in the British countryside. SenSat was founded in 2015 and last year surveyed 9000km of UK highways with c-drones and is a participant in the UK government’s Infrastructure Pathfinder Programme begun in 2017, working with the Civil Aviation Authority (CAA), Department for Transport (DfT), industry partner Costain Group PLC, and innovation center Transport Systems Catapult to assist the government in developing legislation for safe BVLOS operation. The test flight originated near Ditchling, East Sussex, some 30km (18mi) from Gatwick Airport and 22km (14m) from Brighton City Airport, within an airspace boundary zone set by the CAA.
The c-drone, a fixed-wing Delair DT18-HD, was certified for BVLOS last year by France’s Direction générale de l’aviation civile (DGAC) before a 50km (31mi) flight for the RTE electricity network in June 2017. However, the French flight was in closed airspace along electrical pylons; the UK flight overflew fields, farms, roads, a railway line, rivers, and villages. UK airspace is among the most complex in the world, with over 2.5 million Flight Information Region (FIR) flight movements last year according to NATS, the UK air navigation service provider (ANSP).
The Delair is equipped with shortwave radio, wifi, and 3G transceivers, for reliable redundant communications with pilots and tracking software. The preprogrammed 27½ minute Sensat flight began with circles for commlink checks, then proceeded along a route with virtual waypoints. In case of signal loss, the c-drone was programmed to return to the most recent waypoint, then back to the launch point. Flight altitude was programmed at 120m (390ft), adjusted automatically for hills and valleys using the Shuttle Radar Topography Mission (SRTM) database and post-processed kinematic (PPK) GPS for higher resolution than standard civilian GPS. The c-drone carries two cameras, one for live-streaming video to monitoring pilots and a downward-facing 21MP unit for mapping acquisition.
SenSat creates precise 3D digital replicas of mapped sites from topographical surveys, made available through a cloud application dubbed Mapp, which can be used in pre-construction project planning, construction phase monitoring, and large scale asset inspections.