RTE is the French transmission system operator responsible for the public high-voltage electricity transmission network in mainland France. RTE operates, maintains and develops the high and very high voltage network. It guarantees the smooth operation and safety of the electricity system. RTE transports electricity between electricity suppliers (French and European) and consumers, whether they are electricity distributors or industrial companies directly connected to the transmission network. More than 105,000 km of lines between 45,000 and 400,000 volts and 50 cross-border lines connect the French network to 33 European countries, providing opportunities for electricity exchanges that are essential for the economic optimisation of the electricity system. RTE regularly inspects the transmission network, 100,000 km of overhead lines (270,000 pylons), 6,000 km of underground lines and 2,700 substations. The aim is to check the condition of the equipment and its environment: corrosion, state of paintwork, distance from vegetation, ...., etc. RTE is exploring the possibility of automating the inspection of these assets using a fleet of drones (BVLOS, indoor, inbox, etc.).