FLIGHT INVESTIGATION OF VTOL CONTROL AND DISPLAY CONCEPT FOR PERFORMING DECELERATING APPROACHES TO AN INSTRUMENT HOVER

摘要

It is generally acknowledged that the ability of VTOL aircraft to continue routine operation during periods of poor visibility is a necessary condition for economic feasibility in commercial usage. In the past, research efforts oriented toward VTOL terminal-area operation have attempted to attain adequate instrument flight capability by emphasizing either the display or handling qualities aspect of the problems, while paying relatively little attention to the other aspect. None of these studies, however, has demonstrated the capability of decelerating to an instrument hover at a preselected point. This investigation resulted in a VTOL-oriented display and control concept which provided a capability of studying operational aspects of the decelerating approach problem. The flight tests were conducted with a research helicopter equipped with a control augmentation system and a flight-director display, along with more conventional situation displays. The tests documented the maximum deceleration rates that could be achieved, effects of winds, and approach and hover performance.