A method and means for generating a synthetic terrain which is displayed on the screen of a cathode ray tube as a simulated landscape visible to an observer, and for use in conjunction with a vehicle simulator to provide a moving perspective view of a landscape. The scanning beam of the cathode ray tube is modulated with a video signal which is representative of the visual characteristics of the landscape at a point which at any instant is defined by the intersection of the line of sight passing from the observer's eye through the instantaneous scanning point on the cathode ray tube screen with the plane of the simulated landscape.

A system for generating sky, horizon scenes and scenes simulating low visibility in a flight simulator visual system using a television display is shown. Aircraft attitude information is used in a horizon generator to locate the horizon on a line-to-line basis. The information from the horizon generator is modified by functions of visibility range, altitude, time of day and location above or below clouds to develop the proper scenes, such as white for sky below clouds, white for clouds, the blue for sky above clouds and to switch between these synthetically generated scenes and a terrain scene provided by a camera model system or other image generator.

A cockpit-mounted cathode ray tube presents to the pilot a visual equivalent of the approach/landing during obscure visibility of an aircraft which contains a miniature illuminated runway that is being "approached" by a video camera that reproduces the position and position changes of the aircraft with respect to the real runway. Ground-based instrument landing system elements are used to air derive radio information to secure the operation of the device.

A Heads-Up Display system which displays an attitude reference to pilots in order to provide a reference display system as a primary flight instrument. The Heads-up Display system uses a pitch ladder system based on Euler angle data which eliminates the erratic motion or "flip-flop" of the typical pitch ladder which is inherent and unavoidable when pitching near plus or minus 90.degree., by utilizing a flexible graphics display which presents the pilot with a heads-up view as if he were located inside and at the center of an imaginary sphere which has heading and pitch angle information marked on its inner surface. The display of appropriately curved bars as opposed to a straight bar pitch ladder for attitude reference more realistically depicts to the pilot the aircraft situation relative to the outside world. This presentation is more easily and more reliably interpreted by the pilot and simplifies the recognition and recovery from unusual attitudes. In addition, ground track, yaw rate, turn rate information is available over the entire HUD field-of-view, thus there is no need for the pilot to redirect his attention away from his primary point of interest, the velocity vector, to obtain heading and track information. Appropriate equations are evaluated to obtain line-of-sight angles from the aircraft longitudinal axis to the desired pitch and heading points on the pitch ladder display. Such equations are solved by computer techniques for a sufficient number of intersecting points to complete the display and the graphics hardware connects the points to form the segments of the pitch ladder which represent the imaginary lines on the sphere and displays the same in the pilot's field-of-view.

A cockpit display for indicating the assessments made by a performance and failure assessment monitor of the overall performance of an automatic flight control system or of the pilot during the landing maneuver. The display processes signals from the monitor and operates thereon to display a representation of the runway, the expected landing point thereon and the relative uncertainty that the aircraft will land on the predicted spot. After landing the display may show the position of the aircraft on the runway and the expected lateral excursion thereof plus a discrete display of the distance the aircraft will travel before it can be stopped. Other discrete displays are also provided at critical times either to compliment the normal display or in substitution therefor.