Pylon

Pylon is a term with several related meanings. It generally denotes a tall vertical structure serving as a support, gateway, or mounting point. The word is widely used for electrical transmission towers, the monumental gateways of ancient Egyptian temples, and for the mounting hardware on aircraft that carry external stores.

In electric power systems, pylons (transmission towers) carry overhead high-voltage conductors between substations. They are usually lattice steel or reinforced concrete and vary in height, footprint, and the number of circuits carried. Common forms include free-standing lattice towers, guyed towers, and tubular steel poles. They are designed to withstand wind, ice loading, and dynamic line forces, with safety clearances and environmental impacts considered in siting and maintenance.

In ancient Egyptian architecture, a pylon is the monumental gateway to a temple. Pylons consist of massive, sloped walls that taper toward the top and are typically flanked by courtyards and enclosing walls. They are decorated with reliefs and inscriptions that commemorate rulers and religious themes and mark the entrance to the sacred precinct.

In aviation and military contexts, a pylon is a mounting structure on a wing or fuselage used to carry external stores such as fuel tanks or weapons. Pylons must withstand aerodynamic loads, maintain proper separation from the airframe and other stores, and provide connections to the aircraft’s systems. They are integrated into the aircraft’s weight and balance considerations.

Etymology traces the term to the ancient Egyptian gateway called a pylon; in modern English it also designates such gateways and, by extension, the tall transmission towers and aircraft mounting hardware.