Abstract: A self-insulating air delivery system maintains a desired air temperature of the conditioned air supplied thereinto for delivery to an aircraft. The system uses insulating airflow layers; a parallel layer and a counterflow layer. A starting section connects to a PCA unit and delivers conditioned air therefrom to an interior supply hose. The starting section also either creates bleed conditioned air or accepts conditioned insulating air and supplies it to an interior insulating hose that is annularly outward of the supply hose and in which air flows parallel to airflow in the supply hose. A reversing connector indirectly connects the supply hose to the aircraft and reverses the flow of air from the interior insulating hose to flow back toward the PCA unit in an exterior counterflow hose that is annularly outward of the interior insulating hose.