THe NASA Ames Digital Image Generation (DIG) system was purchased from the Link division of Singer Inc. The system provides a simulated out-the- window, visual image for a larg-vertical-motion flight simulator. As originally designed, the DIG can support four visual channels, which represent four aircraft windows with a single pilot eyepoint. The visual system was originally designed to support flight simulations of high altitude, high speed, fixed-wing aircraft. A Helicopter ...