Flight-path and airspeed control during landing approach for powered-lift aircraft

Manual control of flight path and airspeed during landing approach has been investigated for powered-lift transport aircraft. An analysis was conducted to identify the behavior of the aircraft which would be potentially significant to the pilot controlling flight path and airspeed during the approach. The response characteristics found to describe the aircraft behavior were (1) the initial flight-path response and flight-path overshoot for a step change in thrust, (2) the steady-state coupling of flight path and airspeed for a step change in thrust, and (3) the sensitivity of airspeed to changes in pitch attitude. The significance of these response characteristics was evaluated by pilots on a large-motion, ground-based simulator at Ames Research Center. Coupling between flight path and airspeed was considered by the pilot to be the dominant influence on handling qualities for the approach task. Results are compared with data obtained from flight tests of three existing powered-lift V/STOL aircraft

A Balanced Energy Plan for the Interior West

Describes a Balanced Energy Plan for the Interior West region of Arizona, New Mexico, Nevada, Utah, Colorado, Wyoming and Montana. Part of the Hewlett Foundation Energy Series

A Flight Investigation of the STOL Characteristics of an Augmented Jet Flap STOL Research Aircraft

The flight test program objectives are: (1) To determine the in-flight aerodynamic, performance, and handling qualities of a jet STOL aircraft incorporating the augmented jet flap concept; (2) to compare the results obtained in flight with characteristics predicted from wind tunnel and simulator test results; (3) to contribute to the development of criteria for design and operation of jet STOL transport aircraft; and (4) to provide a jet STOL transport aircraft for STOL systems research and development. Results obtained during the first 8 months of proof-of-concept flight testing of the aircraft in STOL configurations are reported. Included are a brief description of the aircraft, fan-jet engines, and systems; a discussion of the aerodynamic, stability and control, and STOL performance; and pilot opinion of the handling qualities and operational characteristics

Flight-test evaluation of STOL control and flight director concepts in a powered-lift aircraft flying curved decelerating approaches

Flight tests were carried out to assess the feasibility of piloted steep curved, and decelerating approach profiles in powered lift STOL aircraft. Several STOL control concepts representative of a variety of aircraft were evaluated in conjunction with suitably designed flight directions. The tests were carried out in a real navigation environment, employed special electronic cockpit displays, and included the development of the performance achieved and the control utilization involved in flying 180 deg turning, descending, and decelerating approach profiles to landing. The results suggest that such moderately complex piloted instrument approaches may indeed be feasible from a pilot acceptance point of view, given an acceptable navigation environment. Systems with the capability of those used in this experiment can provide the potential of achieving instrument operations on curved, descending, and decelerating landing approaches to weather minima corresponding to CTOL Category 2 criteria, while also providing a means of realizing more efficient operations during visual flight conditions

John Dewey et sa glose approfondie de la théorie peircienne de la qualité

Dans un article peu connu sur la doctrine peircienne de la qualité, John Dewey a non seulement précisé la nature et le rôle du qualitatif dans le système des catégories, mais il a également mis en évidence les implications philosophiques et méthodologiques de cette découverte fondamentale. Il s’est attaché à développer cette doctrine et à en chercher les applications dans d’autres écrits essentiels, où la catégorie de la qualité se trouve associée à la production de formes proprement iconiques et à la constitution de formes de l’expérience moins artistiques qu’esthétiques. J’essaie dans cet article de retrouver les racines de la pensée de Dewey dans l’oeuvre de Peirce et de dégager non seulement les rapports qu’entretiennent les deux projets philosophiques, mais aussi leurs capacités heuristiques respectives.In a little known article on Peirce’s doctrine of quality, John Dewey not only defined the role and nature of the domain of quality within the theory of categories, but he also drew attention to the philosophical and methodological implications of Peirce’s fundamental discovery. Dewey endeavoured to develop the doctrine and investigate its applications in a number of essential texts, wherein the category of quality is associated with the production of iconic forms and the establishment of forms of experience which are more aesthetic than artistic. In this article, I attempt to trace the roots of Dewey’s thought in Peirce’s philosophy, and to specify not only the relations between the two philosophies but also their respective heuristic potential

Flight experiments using the front-side control technique during piloted approach and landing in a powered lift STOL aircraft

The essential features of using pitch attitude for glidepath control in conjunction with longitudinal thrust modulation for speed control are described, using a simple linearized model for a powered-lift STOL aircraft operating on the backside of the drag curve and at a fixed setting of propulsive lift. It is shown that an automatic speed-hold system incorporating heave-damping augmentation can allow use of the front-side control technique with satisfactory handling qualities, and the results of previous flight investigations are reviewed. Manual control considerations, as they might be involved following failure of the automatic system, are emphasized. The influence of alternative cockpit controller configurations and flight-director display features were assessed for their effect on the control task, which consisted of a straight-in steep approach flown at constant speed in simulated instrument conditions

Operational experience with a powered-lift STOL aircraft

The experience gained in over four years of STOL operations with the augmentor wing research aircraft and the background of operation of other STOL powered-lift aircraft indicate that the use and percent of lift achieved by powered lift have significant effects on the operational characteristics of STOL aircraft and, therefore, on the performance that can be achieved. A brief description of the augmentor wing including the means by which it achieves its powered lift is presented. Specific problem areas relating to the control of longitudinal flight path are discussed as well as the consequences these might have on the design and operation of this class of aircraft. Particular emphasis is given to the approach and landing phase of flight where the consequences of the powered lift are most pronounced, and the resultant characteristics most different from those of conventional aircraft