Longitudinal flying qualities criteria for single-pilot instrument flight operations

Modern estimation and control theory, flight testing, and statistical analysis were used to deduce flying qualities criteria for General Aviation Single Pilot Instrument Flight Rule (SPIFR) operations. The principal concern is that unsatisfactory aircraft dynamic response combined with high navigation/communication workload can produce problems of safety and efficiency. To alleviate these problems. The relative importance of these factors must be determined. This objective was achieved by flying SPIFR tasks with different aircraft dynamic configurations and assessing the effects of such variations under these conditions. The experimental results yielded quantitative indicators of pilot's performance and workload, and for each of them, multivariate regression was applied to evaluate several candidate flying qualities criteria

Vertical transportation planning in buildings

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.This thesis is submitted for the degree of Doctor of Engineering in Environmental Technology. The degree is awarded for industrially relevant research, based in industry, and supported by a programme of development courses. This project aims to contribute to a reduction in the environmental burdens of vertical transportation systems. The author has carried out an environmental assessment showing that the dominating environmental burdens of vertical transportation systems arise from their use of electricity while in operation in buildings. An assessment of traffic demand has concluded that we are probably over-sizing lifts, and are therefore installing systems that consume more energy than necessary. Traffic planning techniques for single and double deck lifts have been reviewed and developed. The kinematics (motion) of lifts has been studied. New formulae have been derived that allow us to plot travel profiles for any input of journey distance, maximum velocity, maximum acceleration and maximum jerk. Taking these journey profiles as inputs, a mathematical model of a DC Static Converter Drive has been developed. The model can be used to calculate the energy consumption of any individual lift trip. A lift simulation program has been developed. The program uses the research in traffic, kinematics and motor modelling as a basis for developing energy saving lift control strategies.Engineering and Physical Sciences Research Council; Ove Arup Partnership; and, Chartered Institution of Building Services Engineer

Development of the reentry flight dynamics simulator for evaluation of space shuttle orbiter entry systems

A nonlinear, six degree of freedom, digital computer simulation of a vehicle which has constant mass properties and whose attitudes are controlled by both aerodynamic surfaces and reaction control system thrusters was developed. A rotating, oblate Earth model was used to describe the gravitational forces which affect long duration Earth entry trajectories. The program is executed in a nonreal time mode or connected to a simulation cockpit to conduct piloted and autopilot studies. The program guidance and control software used by the space shuttle orbiter for its descent from approximately 121.9 km to touchdown on the runway

Aeronautical Engineering: A special bibliography with indexes, supplement 67, February 1976

This bibliography lists 341 reports, articles, and other documents introduced into the NASA scientific and technical information system in January 1976

Quality and quantity of service in lift groups

This research was focused on quality of service experienced by passengers in lift systems where multiple cars are sharing same shafts (multi car lift systems) and destination control. These modern lift systems have opportunities and constraints for control algorithms arising by existing and additional quality of service criteria. These additional criteria have rarely been considered in existing literature, control algorithms or traffic analysis. The overall aim of the research was to determine and analyse existing and new quality of service criteria for destination control systems and multi car lift systems in terms of traffic handling and developing lift control concepts considering these criteria. Therefore, the impact on passengers’ quality of service was reviewed using psychology of waiting principles. Detailed definition and analysis was done for reverse journeys in destination control systems and departure delays with a focus on multi car lift systems. To develop and analyse control algorithms known event based traffic simulation, round trip time calculation and Monte Carlo simulation were extended and applied. Traffic control algorithms and concepts were developed to improve passenger experience when using lifts. Additional to dispatching algorithms equations for improved lift kinematics and controlled stopping distances were derived to reduce departure delays in multi car lift systems. Possible improvements were shown in case studies. Compared to traditional lift systems, special opportunities and constraints of a circulating multi car lift system in traffic handling were explored and analysed. New cycle time calculations for shuttle and local group applications were developed. Results were provided using case studies, and necessary control concepts were addressed. With the results of this research, better understanding and assessments of multi car lift systems and destination controls are possible. The traffic control algorithms explored help to build better lift controllers, considering passengers perception. The introduced traffic analysis methods for circulating multi car lift systems support lift planning

Design and Construction of a 1/3-Scale, 1986 Cessna 172P Flight-Test Aircraft

The incredible cost of prototype flight testing can be a very limiting factor in the optimization of new designs as they proceed from the drawing board to the flight line. The use of low-cost scaled models to predict full-scale prototype performance is the focus of this project. It will be shown that by strictly following geometric and dynamic scaling criteria, the scaled aircraft\u27s flight performance can be predictably related to the full-scale aircraft\u27s performance. Many companies have performed scaled flight-testing of Remotely Piloted Vehicles (RPV\u27s) and there is much speculation as to the results of these tests, but non-proprietary information about low-cost, scaled flight-testing is rare. The focus of the project at hand, therefore, is to compare the in-flight performance characteristics of a 1/3-scale flying prototype to the in-flight performance characteristics of a well-known full-scale flying prototype, a 1986 Cessna 172P. Much flight testing has been done by ERAU\u27s department of Aerospace Engineering on the 1986 172P so that using this aircraft as the model for determining the validity of the scaling hypotheses is obvious. The author, with the aid of students from capstone design classes at ERAU, designed and constructed a 1/3-scale replica 172 as the flying test-bed from which a series of future scaled prototype projects will draw vital conceptual and procedural ideas. The model 172 will be flown by remote control and will have an array of on-board sensors to collect information about key flight characteristics. Along with the on-board data acquisition system and real-time display ground base, the sub-scale aircraft also has a real-time video/audio link to the ground to allow the pilot to fly maneuvers using the same flight cues as they would if in the real aircraft

An avionics sensitivity study. Volume 1: Operational considerations

Equipment and operational concepts affecting aircraft in the terminal area are reported. Curved approach applications and modified climb and descent procedures for minimum fuel consumption are considered. The curved approach study involves the application of MLS guidance to enable execution of the current visual approach to Washington National Airport under instrument flight conditions. The operational significance and the flight path control requirements involved in the application of curved approach paths to this situation are considered. Alternative flight path control regimes are considered to achieve minimum fuel consumption subject to constraints related to air traffic control requirements, flight crew and passenger reactions, and airframe and powerplant limitations

Centrifugally Stiffened Rotor: Eternal Flight as the Solution for 'X': NIAC Phase I Final Report

Flight has always captured man's imagination. This is evidenced by the great variety of aerial vehicles that exist today. Everything from fixed-wing to rotorcraft; satellites to spaceships;mono-wing to quadrotor. However, despite the wide variety of flying vehicles, not one of them has attained eternal flight. Accomplishing this feat is one of the great challenges still facing the aviation community. Motivation Achieving eternal flight opens the doors to atmospheric satellites. Existing satellites have a great number of capabilities that enrich our lives; however,their distance from the surface of the earth precludes certain types of transmission capabilities. Once eternal flight is achieved, that vehicle can serve the same role as ordinary satellites, but its close proximity will allow for real time two way communications,like wireless broadband internet. And with active controls, atmospheric satellites would not be constrained to geosynchronous orbits, like our existing satellite technology. Many projects are under way to achieve this goal;however, most of these research efforts follow the same design methodology, and have exhausted the limits of this particular design. This concept introduces a completely new aerial vehicle structure,which uses the best features of fixed-wing and rotorcraft designs. Combining the best features of different classes of aircraft, expands the capabilities beyond what either one can achieve on its own

Design and simulation of a descent controller for strategic four-dimensional aircraft navigation

A time-controlled navigation system applicable to the descent phase of flight for airline transport aircraft was developed and simulated. The design incorporates the linear discrete-time sampled-data version of the linearized continuous-time system describing the aircraft's aerodynamics. Using optimal linear quadratic control techniques, an optimal deterministic control regulator which is implementable on an airborne computer is designed. The navigation controller assists the pilot in complying with assigned times of arrival along a four-dimensional flight path in the presence of wind disturbances. The strategic air traffic control concept is also described, followed by the design of a strategic control descent path. A strategy for determining possible times of arrival at specified waypoints along the descent path and for generating the corresponding route-time profiles that are within the performance capabilities of the aircraft is presented. Using a mathematical model of the Boeing 707-320B aircraft along with a Boeing 707 cockpit simulator interfaced with an Adage AGT-30 digital computer, a real-time simulation of the complete aircraft aerodynamics was achieved. The strategic four-dimensional navigation controller for longitudinal dynamics was tested on the nonlinear aircraft model in the presence of 15, 30, and 45 knot head-winds. The results indicate that the controller preserved the desired accuracy and precision of a time-controlled aircraft navigation system

Autonomous landing of fixed-wing aircraft on mobile platforms

E n esta tesis se propone un nuevo sistema que permite la operación de aeronaves autónomas sin tren de aterrizaje. El trabajo está motivado por el interés industrial en aeronaves con la capacidad de volar a gran altitud, con más capacidad de carga útil y capaces de aterrizar con viento cruzado. El enfoque seguido en este trabajo consiste en eliminar el sistema de aterrizaje de una aeronave de ala fija empleando una plataforma móvil de aterrizaje en tierra. La aeronave y la plataforma deben sincronizar su movimiento antes del aterrizaje, lo que se logra mediante la estimación del estado relativo entre ambas y el control cooperativo del movimiento. El objetivo principal de esta Tesis es el desarrollo de una solución práctica para el aterrizaje autónomo de una aeronave de ala fija en una plataforma móvil. En la tesis se combinan nuevos métodos con experimentos prácticos para los cuales se ha desarrollado un sistema de pruebas específico. Se desarrollan dos variantes diferentes del sistema de aterrizaje. El primero presta atención especial a la seguridad, es robusto ante retrasos en la comunicación entre vehículos y cumple procedimientos habituales de aterrizaje, al tiempo que reduce la complejidad del sistema. En el segundo se utilizan trayectorias optimizadas del vehículo y sincronización bilateral de posición para maximizar el rendimiento del aterrizaje en términos de requerimientos de longitud necesaria de pista, pero la estabilidad es dependiente del retraso de tiempo, con lo cual es necesario desarrollar un controlador estabilizador ampliado, basado en pasividad, que permite resolver este problema. Ambas estrategias imponen requisitos funcionales a los controladores de cada uno de los vehículos, lo que implica la capacidad de controlar el movimiento longitudinal sin afectar el control lateral o vertical, y viceversa. El control de vuelo basado en energía se utiliza para proporcionar dicha funcionalidad a la aeronave. Los sistemas de aterrizaje desarrollados se han analizado en simulación estableciéndose los límites de rendimiento mediante múltiples repeticiones aleatorias. Se llegó a la conclusión de que el controlador basado en seguridad proporciona un rendimiento de aterrizaje satisfactorio al tiempo que suministra una mayor seguridad operativa y un menor esfuerzo de implementación y certificación. El controlador basado en el rendimiento es prometedor para aplicaciones con una longitud de pista limitada. Se descubrió que los beneficios del controlador basado en el rendimiento son menos pronunciados para una dinámica de vehículos terrestres más lenta. Teniendo en cuenta la dinámica lenta de la configuración del demostrador, se eligió el enfoque basado en la seguridad para los primeros experimentos de aterrizaje. El sistema de aterrizaje se validó en diversas pruebas de aterrizaje exitosas, que, a juicio del autor, son las primeras en el mundo realizadas con aeronaves reales. En última instancia, el concepto propuesto ofrece importantes beneficios y constituye una estrategia prometedora para futuras soluciones de aterrizaje de aeronaves.In this thesis a new landing system is proposed, which allows for the operation of autonomous aircraft without landing gear. The work was motivated by the industrial need for more capable high altitude aircraft systems, which typically suffer from low payload capacity and high crosswind landing sensitivity. The approach followed in this work consists in removing the landing gear system from the aircraft and introducing a mobile ground-based landing platform. The vehicles must synchronize their motion prior to landing, which is achieved through relative state estimation and cooperative motion control. The development of a practical solution for the autonomous landing of an aircraft on a moving platform thus constitutes the main goal of this thesis. Therefore, theoretical investigations are combined with real experiments for which a special setup is developed and implemented. Two different landing system variants are developed — the safety-based landing system is robust to inter-vehicle communication delays and adheres to established landing procedures, while reducing system complexity. The performance-based landing system uses optimized vehicle trajectories and bilateral position synchronization to maximize landing performance in terms of used runway, but suffers from time delay-dependent stability. An extended passivity-based stabilizing controller was implemented to cope with this issue. Both strategies impose functional requirements on the individual vehicle controllers, which imply independent controllability of the translational degrees of freedom. Energy-based flight control is utilized to provide such functionality for the aircraft. The developed landing systems are analyzed in simulation and performance bounds are determined by means of repeated random sampling. The safety-based controller was found to provide satisfactory landing performance while providing higher operational safety, and lower implementation and certification effort. The performance-based controller is promising for applications with limited runway length. The performance benefits were found to be less pronounced for slower ground vehicle dynamics. Given the slow dynamics of the demonstrator setup, the safety-based approach was chosen for first landing experiments. The landing system was validated in a number of successful landing trials, which to the author’s best knowledge was the first time such technology was demonstrated on the given scale, worldwide. Ultimately, the proposed concept offers decisive benefits and constitutes a promising strategy for future aircraft landing solutions