Passenger's views of commuter aircraft are considered. The fact that passengers seek inconsistent combinations of service features such as frequency, load factor, aircraft size and fare levels and that the task of the designer and airline manager are particularly difficult is acknowledged. The study draws on personal experience and on the results of surveys of passengers, to highlight the areas where passengers seek improvements. It is concluded that users require more space per passenger, more cabin stowage space and lower cabin noise levels. Growing congestion means that all commuter aircraft should be capable of operating from secondary runways. More customer research is suggested as being needed before new designs are frozen. N91-11721# Aerospatiale, Suresnes (France). THE EVOLUTION OF REGIONAL AIR TRAFFIC ESA C04 c04 N91-11722# Airport Authority, Munich (Germany, F.R.). The development of regional air traffic, defined as the sector of aviation which increases the density of the domestic and international scheduled air traffic network with the aim of developing the area covered by the network, is described. It normally employs modern turboprop aircraft, but the jump to the jet age is already W. Hergesell In DGLR, European Forum: The Evolution of The influences of aircraft size and technology are discussed. It is suggested that the maintainability is affected by the philosophy of the aircraft manufacturer and the design and by the following factors: size of the aircraft; technology used in the aircraft and their systems; age of the aircraft (e.g., hours since new/cycles since new); complexity of the installed engines and systems; qualification of maintenance personnel and inspectors required; special tools and their availability; sophisticated test equipment; size of hangars and other facilities; choosen maintenances systems; reliability monitoring; product and material support by manufacturers; product improvement by manufacturers; and feedback of operator's experience to manufacturers. ESA N91-11725# Motoren- und Turbinen-Union Muenchen G.m.b.H. (Germany, F.R.). ENGINE MAINTAINABILITY: OBJECTIVES AND METHODS c07 A. Senft In DGLR, European Forum: The Evolution of Regional Major considerations used to improve engine maintainability are identified. The basis for maintainability features are a lot of requirements. These requirements are defined by the customer and created using several analyses. Criteria for good maintainability features of an engine are considered to be design requirements. The engine shall be designed for ease and simplicity of maintenance. Modular concept and quantitative/qualitative design targets are necessary to meet specified requirements. Maintainability reviews and maintainability demonstrations have to be conducted during engine development to show that the requirements given have been met. ESA NEW TECHNOLOGIES AND CUSTOMER ACCEPTANCE c05 The reasons pushing aircraft manufacturers towards new technologies and the acceptance of such technologies by regional airlines are considered. Some specifics of the commuter market with regard to this acceptance are described. Precise examples based on experience gained during the design phase and marketing of the ATR 42 and ATR 72, which are recognized new technology commuterliners, are given. These examples include the Electronic N91-11728# Messerschmitt-Boelkow-Blohm G.m.b.H., Hamburg (Germany, F.R.). Fatigue and Fracture Mechanics Dept. FULL SCALE FATIGUE AND DAMAGE TOLERANCE TESTING OF MODERN TRANSPORT AIRCRAFT c05 H.-J. Schmidt and B. Brandecker In DGLR, European Forum: The Evolution of Regional Aircraft Technologies and Certification 1989 p 147-15 (For primary document see N91-11707 03-03) Avail: NTIS HC/MF A10 The essential aspects of major full scale fatigue and damage tolerance tests for metallic structure are described using the Airbus A320 example. Details about test philosophy, test ioad program, test execution and supporting coupon testing are given, which comprises more than 15 years experience of fatigue and damage tolerance testing for metallic structure of aircraft and the results of numerous discussions with European and other airworthiness authorities. Specific aspects of regional aircraft full scale testing are discussed with respect to definition of test specimen, test speed, simplification of test spectrum and justification of repairs. ESA N91-11729# Deutsche Gesellschaft fuer Luft- und Raumfahrt, DIGITAL GLASS COCKPIT FOR COMMUTER AIRCRAFT c06 The evolution of cockpit information systems is described and an outlook on future generation smaller and more cost and weight sensitive aircrafts is derived. Systems architecture and display formats are described. The A-310 and A-320 systems were addressed. ESA Robert Hinsinger In DGLR, European Forum: The Evolution of 1989 Regional Aircraft Technologies and Certification p 181-18 (For primary document see N91-11707 03-03) Avail: NTIS HC/MF A10 For three sizes of commuter aircraft for the next decade (30, 60, 90 seaters), different types of propulsion are considered: modern propellers, where Mach number (M) is greater than 0.5 and less than 0.6; open rotor systems where M is greater than 0.7 and less than 0.78; ducted propellers where M 0.78, and turbofan where M = 0.78. Requirements are defined for each aircraft category. An optimization is done to minimize the operating cost. The results are provided versus number of seats and range. ESA = H. E. Groenewald and E. Wuerzinger In DGLR, European Forum: The Evolution of Regional Aircraft Technologies and Certification 1989 p 189-19 (For primary document see N91-11707 03-03) Avail: NTIS HC/MF A10 The various applications of turboprop and turbofan engines in regional aircraft are explained. Reference is made to the differing performance objectives for these aircrafts. It is shown that, in the adaptation of the engine to the aircraft, the climb phase of flight is the most significant factor for engine dimensioning. Areas of development emphasis from the point of view of market requirements are discussed with regard to their impact on design. It is shown that engines of simple design with low mechanical and thermal stressing of components but with high component efficiencies form the ideal basis for regional aircraft propulsion. This concept is seen to provide for low procurement and maintenance costs. ESA N91-11734# Motoren- und Turbinen-Union Muenchen G.m.b.H. (Germany, F.R.). c07 PW300: POWERPLANT FOR REGIONAL AIRCRAFT The PW300, a modern high bypass turbofan, is addressed. It will initially have a takeoff thrust of about 22 KN (5,000 Lbf) and compared to existing turbofans of this class will offer up to a 20 percent reduction in specific fuel consumption. A technical description of each engine component is given as well as an explanation of how the exceptional performance is achieved. The growth potential and derivative versions of the engine are discussed. ESA N91-11735# Civil Aviation Authority, London (England). THE EUROPEAN CERTIFICATION PROCESS R. Ashford In DGLR, European Forum: The Evolution of Regional Robert E. David 1 Jul. 1990 85 p (AD-A225225; DOT/FAA/AOV-90-1) Avail: NTIS HC/MF A05 CSCL 01/2 The location of an aircraft involved in an accident or incident may be documented by the National Transportation Safety Board and the Federal Aviation Administration during the course of their investigation. When available, it will appear in the record of the individual investigation. However, this location information is not available from either of these agencies in a summary form. Compiled in this document is the location relative to the runway of these accidents/incidents for aircraft involved in commercial air transportation in the United States. Accidents/incidents that occurred from 1978 to 1987 were studied. Since it is intended that this information will be used mainly to make decisions on individual airports, no attempt was made to reach conclusions or make recommendations based on the data. The accidents/ incidents used were categorized as undershoots, landings off the runway, veeroffs, overruns, and other in the vicinity of the airport. The aircraft location was recorded in terms of the distance along the runway centerline or extended centerline (X distance) and the perpendicular distance from the centerline or extended centerline (Y distance). GRA 04 AIRCRAFT COMMUNICATIONS AND NAVIGATION Includes digital and voice communication with aircraft; air navigation systems (satellite and ground based); and air traffic control. For related information see also 17 Space Communications, Spacecraft Communications, Command and Tracking and Communications and Radar. N91-11739# Analytic Sciences Corp., Reading, MA. (AD-A224814; TASC-TIM-5834-1-1; USCG/ONSCEN-01-90) Enhancement of the Omega System Availability Model is presented which: (1) widen the range of application of the model; (2) increase the efficiency fo the model algorithm; and (3) broaden the model to include more realistic characterization of the signal coverage parameters. The system availability model/algorithm is modified to apply at the geographic area unit (cell) and multi-cell level. Further modifications include: a precomputation method to speed calculation and extension of the coverage database (interpolation) from four months to twelve months. The system availability model is extended to include the effects of random signal and noise variations. The augmented model structure is consistent with probabilistic definition of the Omega System Availability Index (PSA). GRA N91-11740# Technische Univ., Brunswick (Germany, F.R.). Inst. fuer Verkehr, Eisenbahnwesen und Verkehrssicherung. UTILIZATION OF A TESTING UNIT FOR THE EXAMINATION OF SSR MODE S, FOLLOWING A TCAS PRESENTATION [EINSATZ EINER MESSANLAGE ZUR UNTERSUCHUNG VON SSR MODE S ANLAESSLICH EINER TCAS PRAENSENTATION] Wolfgang Detlefsen and Roland Mallwitz Apr. 1990 44 p In GERMAN (ETN-90-97891) Avail: NTIS HC/MF_A03 The number of moves in air space is continually increasing. Therefore, conventional concepts of flight safety and the existing air space structures have reached their limits. New forms of guidance and supervision of the air traffic are required, such as Secondary Surveillance Radar (SSR) and the Threat Alert and Collision Avoidance Systems (TCAS). Methods are developed which, on the one hand, describe the behavior simulated board and ground appliances in real traffic sequence, and, on the other hand, allow to simulate and analyze basic functions of the system, onboard and on ground in real environment. ESA N91-11741# Technische Univ., Brunswick (Germany, F.R.). Inst. Klaus-Peter Berg May 1990 122 p In GERMAN The examinations presented are based on the analysis of recorded real traffic sequences. The exploitation of input data and the associated data preparation are illustrated. The traffic distribution is examined within the coverage of various sensors. Starting with the geographical and temporary distribution, the obstacle loads inside the radar stream are determined, so that first conclusions on the charge of future mode S sensor can be deduced. These real in-beam distributions are extracted as input data, in order to assess various processes of the roll call scheduling. After examination of basic processes an optimal algorithm is developed. The processes are evaluated and tested, using synthetic and real traffic sequences. A simulation is presented to determine the time budget required for surveillance transactions. The fixing of mode S data links in the ATN (Aeronautical Telecommunication Network) is represented. It allows the general concept to be drafted. Mode S subnetwork, and a conversion in mode S internal data formats are discussed. The efficiency reduction resulting from the ATN concept is examined. The mode S specific communication formats are stated in order to discuss the requirements for mode S duties. ESA N91-11742# European Space Agency, Paris (France). Karlheinz Hurrass (Deutsche Forschungs- und Versuchsanstalt fuer The results of the tests performed on the Global Positioning System (GPS) since the seventies are reported. In 1986, 7 satellites were available for research purposes. The accuracy of the GPS was tested. A Litton LTN-700 receiver suitable for the C/A code was used. The reference flight paths were determined by the avionics flight evaluation system. The position errors measured consisted of high frequency and low frequency noise. The standard deviation of the latter was about 30 meters. ESA N91-11743# Federal Aviation Administration, Washington, DC. TERMINAL AREA FORECASTS: FY 1990-2005 (AD-A225227; FAA-APO-90-6) Avail: NTIS HC/MF A23 CSCL 01/5 Forecasts are presented of aviation activity of 854 airports in the U.S. for fiscal years 1990 to 2005. These include 398 airports with FAA air traffic control towers and radar approach control service and 17 FAA contract towers. For each airport, detailed forecasts are made for the four major uses of the air traffic system: air carriers, air taxi/commuters general aviation, and military. Summary tables contain national, FAA regional, and State aviation data and other airport specific highlights. The forecasts were prepared to meet the budget and planning needs of the FAA and to provide airport-specific information that can be used by State and local aviation authorities, the aviation industry, and the general public. GRA N91-11744# Royal Air Force Coll., Cranwell (England). Dept. of Electrical and Electronic Engineering. D. J. Young 1990 167 p The current navigational techniques available for use in the present generation of strategic cruise missiles are studied. The NAVSTAR Global Positioning System (GPS) and its possible integration with an Inertial Navigation System (INS), using a multi state Kalman filter, is described. The use of an integrated GPS/INS produced a navigational system that is capable of providing positional data in X, Y, and Z planes to a high degree of accuracy. Proposals are made to utilize this positional knowledge in a future cruise missile, to enable it to terrain follow and terminally guide with no external sensors operating, hence, reducing the missiles chances of detection. Simulation results suggest that such a cruise missile would be able to fly lower than the present generation of missiles, while maintaining a safe separation from the ground and a similar terminal accuracy to the current active cruise missiles. ESA N91-11745# Cranfield Inst. of Tech., Bedford (England). Center for Transport Studies. THE IMPACT OF EXCHANGE RATES ON AIR TRAFFIC DEMAND M.S. Thesis T. J. Patch Sep. 1990 161 p (ETN-90-98220) Copyright Avail: NTIS HC/MF_A08 A study to identify the principal factors explaining air traffic demand on two long and two short haul routes, between the United Kingdom and Switzerland is presented. Particular attention is paid to analyzing the influence of exchange rates on traffic levels in each market segment on each route. Exchange rates alone are seen to be an inadequate explanatory variable, and the interrelationship between exchange rates and relative inflation rates is considered. The role of leads and lags in the relationship between air traffic and exchange rates adjusted by inflation is analyzed. The variables affecting air traffic and the specific characteristics of the routes concerned are reviewed. Econometric models are developed using multiple regression analysis and the significant causal variables affecting air traffic in each market segment are identified. The application of the models to forecasting future demand is demonstrated. ESA N91-11721# Aerospatiale, Suresnes (France). THE EVOLUTION OF REGIONAL AIR TRAFFIC Danielle Kahan In DGLR, European Forum: The Evolution of Regional Aircraft Technologies and Certification 1989 p 111-11 (For primary document see N91-11707 03-03) Avail: NTIS HC/MF A10 N91-11722# Airport Authority, Munich (Germany, F.R.). REGIONAL AIR TRAFFIC INTO INTERNATIONAL AIRPORTS: THE DEVELOPMENT IN REGIONAL AIR TRAFFIC P. Trautmann and C. Parau In DGLR, European Forum: The Evolution of Regional Aircraft Technologies and Certification 1989 p 117-12 (For primary document see N91-11707 03-03) Avail: NTIS HC/MF A10 N91-11723# Eurocontrol Agency, Brussels (Belgium). AIR TRAFFIC CONTROL ASPECTS FOR THE TIME BEYOND 1992 Hansjuergen von Villiez In DGLR, European Forum: The Evolution 1989 of Regional Aircraft Technologies and Certification p 121-12 (For primary document see N91-11707 03-03) Avail: NTIS HC/MF A10 05 AIRCRAFT DESIGN, TESTING AND PERFORMANCE Includes aircraft simulation technology. For related information see also 18 Spacecraft Design, Testing and Performance and 39 Structural Mechanics.For land transportation vehicles see 85 Urban Technology and Transportation. N91-11746 Georgia Inst. of Tech., Atlanta. A METHOD OF COMPUTING THE AERODYNAMIC A method is derived for determining the combined aerodynamic effects of a lifting rotor system in the presence of a non-lifting fuselage. The method allows for the full aerodynamic interaction of the lifting rotor blades, the non-lifting body, and the wake sheets trailing from the rotor blades. The wake sheets are allowed to convect with the local induced velocities, creating a distorted wake geometry. The method models the fluid viscous effects by confining these effects to regions adjacent to the bodies and to the wake sheet. The flow outside these regions is modelled as an incompressible potential. A vortex lattice system consisting of discrete vortex filaments is used to represent the lifting rotor system and rotor wake. The non-lifting fuselage is modelled with constant strength source panels. The method develops the trailing wake system by time marching from an initial impulsive start. Azimuthal dependent velocities and pressures are predicted. The predictions are compared with other analysis and experimental data. N91-11747# Dissert. Abstr. Technische Univ., Berlin (Germany, F.R.). Sonderfurschungsbereich 203. A MODULUS FOR FLIGHT SIMULATION IN A COMPUTER RECHNERUNTERSTUETZTEN ENTWURF VON P. Matsiridis Feb. 1990 84 p In GERMAN A high capacity Computer Aided Design (CAD) system for an aircraft preliminary design was developed. During the research work, it appeared necessary to increase the analysis accuracy of the concept project through a simulation modulus. The modulus for flight simulation is presented. The motivation for its acceptance in the system is explained. The motion equations are determined and the moments and forces working on the aircraft are calculated. The problematics of the critical values of the system variables is explained, using the flight mechanical model built in this connection. The results of the representative simulation tasks are indicated. N91-11748# Naval Postgraduate School, Monterey, CA. (AD-A225400) Avail: NTIS HC/MF A05 CSCL 01/1 ESA H-Infinity optimal control theory, based on singular value loop shaping, is used to synthesize a controller for the statically unstable longitudinal dynamics of X-29 aircraft. Two design cases are studied: 2-input 2-output; and 3-input 3-output cases. H-Infinity theory provides a direct, effective procedure for synthesizing control laws satisfying specified performance objectives and robustness specifications. The 2 I/O case has better performance, a better GRA response and is more robust, than 3 I/O case. Avail: Univ. Microfilms Order No. DA9016521 Any knowledge-based system that is to be placed in the cockpit must deal with a wealth of time-varying data, and do so in real time. An avionics knowledge-based system thus requires a conventional signal processing front end to identify relevant signal characteristics, a knowledge representation scheme that lends itself naturally to the representation of uncertain numeric data, and an efficient, interruptible inferencing method. A hardware architecture for knowledge-based avionics systems is proposed which consists of a signal processor and one or more symbol processors. The blackboard paradigm is proposed as the basis for the software architecture. Dempster-Shafer theory is used to express uncertain numerical data. It is shown that the Dempster-Shafer formalism and the four-valued logic of Belnap are complementary, allowing numeric and non-numeric expressions of uncertainty to co-exist. It is also demonstrated that the Kalman filter, a common software component of avionics systems, can be used to provide uncertainty information about numeric data to a Dempster-Shafer evidential reasoning system. An initial software implementation developed in the Ada programming language is discussed. Dissert. Abstr. N91-11715# British Aerospace Public Ltd. Co., Woodford (England). THE CERTIFICATION OF THE AVIONIC SYSTEMS ON THE B. Medda In DGLR, European Forum: The Evolution of Regional Aircraft Technologies and Certification 1989 p 47-51 (For primary document see N91-11707 03-03) Avail: NTIS HC/MF A10 |