To better understand the phenomena associated with electrostatic charges and potential distribution over vertical conductors, this work describes preliminary results obtained with a tethered drone that is used to lay vertically a 100-m long-stranded copper wire. Several flights were conducted in fair weather conditions. In the first configuration, a conductive spherical shell with a spool for the wire is placed in a Teflon holder and used for ensuring that the charges inducted on the conductive body do not produce any corona from the bottom of the system. A field mill is placed below the sphere at a fixed distance, and its measurement can be used as a reference to the charge distribution over the sphere during the flights. The second configuration consists of grounding the bottom sphere, taking the null potential up to the tip of the wire that is deployed. In this setup, several approaches for measuring currents were explored.Peer ReviewedPostprint (published version