A unit includes a glidepath aerial and a support organ designed to be mounted on the front landing gear of an aircraft, with the landing gear forming an electrically conductive ground plane. The aerial is mounted on the support organ and is electrically insulated from this support organ by insulating elements. The support organ has a longitudinal dimension at least equal to around one quarter of the wavelength λ at which the aerial functions, so that the distance separating this aerial and the ground plane is greater than λ/4, and the aerial also has a transmission line designed to connect the aerial to a receiver in the aircraft. The transmission line is surrounded by an electromagnetic shielding element serving as a faradization screen for the transmission line, and designed to be electrically connected to the ground plane.