Editing Head-up display (section)

=== VTOL/STOL approaches and landings ===
During the 1980s, the United States military tested the use of HUDs in vertical take off and landing (VTOL) and short take off and landing (STOL) aircraft. A HUD format was developed at [[NASA]] [[Ames Research Center]] to provide pilots of VTOL and STOL aircraft with complete flight guidance and control information for [[Instrument Landing System#ILS categories|Category III C]] terminal-area flight operations. This includes a large variety of flight operations, from STOL flights on land-based runways to VTOL operations on [[aircraft carrier]]s. The principal features of this display format are the integration of the flightpath and pursuit guidance information into a narrow field of view, easily assimilated by the pilot with a single glance, and the superposition of vertical and horizontal situation information. The display is a derivative of a successful design developed for conventional transport aircraft.<ref>Vernon K. Merrick, Glenn G. Farris, and Andrejs A. Vanags. "A Head Up Display for Application to V/STOL Aircraft Approach and Landing". NASA Ames Research Center 1990.</ref>