Airborne ground penetrating radar is a suitable tool to perform cost-effective surveys of the underground of large possibly nonaccessible areas. To tackle the imaging problem underlying this technology, we propose a regularized inverse scattering procedure. The capabilities of the approach to achieve a stable solution and its imaging performance are first assessed against synthetic data. Then, results obtained by processing data collected by means of a gated stepped frequency system mounted on a helicopter are provided as examples of on-field test cases.