Author: A-5 Aerospace Landing Gear Systems Committee Publisher: ISBN: Category : Languages : en Pages : 0
Book Description
This SAE Aerospace Information Report (AIR) provides an overview of the tire properties, strut properties, damper properties, and other landing gear mechanical properties that contribute to shimmy stability and are required for shimmy analysis. A variety of analysis techniques and assumptions are presented. This report provides information on the contributions of each landing gear component to shimmy stability. Landing gear shimmy design considerations, modeling assumptions, and analysis techniques are provided. The report fills a need for a document that addresses landing gear shimmy behavior and shimmy analysis broadly but concisely from the perspective of aircraft landing gear design and analysis. Other resources in the shimmy literature are more focused on specific components of shimmy modeling, such as tire modeling, or are documenting research on specific landing gears and aircraft.
Author: Jocelyn I. Pritchard Publisher: ISBN: Category : Aerodynamics Languages : en Pages : 22
Book Description
On of the problems facing the aircraft community is landing gear dynamics, especially shimmy and brake-induced vibration. Shimmy and brake-induced vibrations can lead to accidents due to excessive wear and shortened life of gear parts and contribute to pilot and passenger discomfort. To increase understanding of these problems, a literature survey was performed. The major focus is on work from the last ten years. Some older publications are included to understand the longevity of the problem and the background from earlier researchers. The literature survey includes analyses, testing, modeling, and simulation of aircraft landing gear; and experimental validation and characterization of shimmy and brake-induced vibration of aircraft landing gear. The paper presents an overview of the problem, background information, and a history of landing gear dynamics problems and solutions. Based on the survey an assessment and recommendations of the most critically needed enhancements to the state of the art will be presented. The status of Langley work contributing to this activity will be given.
Author: Gordon Westly Davidson Publisher: ISBN: Category : Languages : en Pages :
Book Description
ELGEAR was a UK government/industry partnership created in 2006 to research electrical technology in aircraft landing gear systems. The project designed, built and ground tested electrical technology for a Landing Gear Extension/Retraction system (LGERS) and Nose Wheel Steering systems (NWS) for a 120 passenger aircraft. One thread of this research, and the topic of the present thesis, was to develop analysis methods and tools to investigate the effects of shimmy. Shimmy is the self excited vibration of a castored wheel assembly. It may be experienced on assemblies such as wheel chairs, shopping trolleys, motor cycles, and it is particularly prevalent on aircraft landing gears. Developed within this report is a generic set of system shimmy requirements to guide future engineers. Several models are developed from first principles, allowing a potential design to be quickly evaluated and damper sizes determined. A detailed Multi-Body Systems model has been created using the software modelling package ADAMS. The model includes a detailed representation of mass and inertia properties, stiffness's, friction and tyre properties. The report includes a detailed method to determine the tyre parameters compatible with the ADAMS PAC2002 formulation (magic tyre formula). The dynamic model is simulated to investigate the landing gear's behaviour to each requirement and is a significant enhancement to the models developed using first principles. To explore the influence of higher frequency tyre dynamics, a model incorporating a simplified SWIFT tyre model is generated from first principles. The report concludes with a validation of the methods and tools. Test results are used to validate several aspects of the tyre model, and a comparison between hand derived models and the detailed model provides a thorough check of modelling practices.
Author: Robert Kyle Schmidt Publisher: SAE International ISBN: 0768082463 Category : Technology & Engineering Languages : en Pages : 138
Book Description
The aircraft landing gear system is relatively unique on board an aircraft—it is both structure and machine, supporting the aircraft on the ground, yet providing functions such as energy absorption during landing, retraction, steering, and braking. Advances in Aircraft Landing Gear is a collection of eleven hand-picked technical papers focusing on the significant advancements that have occurred in this field concerning numeric modeling, electric actuation, and composite materials. Additionally, papers discussing self-powered landing gear and more electrical overall aircraft architectures have been included. The content of Advances in Aircraft Landing Gear is divided into two sections: Analysis and Design Methods; and Electric Actuation, Control, and Taxi. For those looking for more information on aircraft landing gears, the SAE A-5 committee (the Aerospace Landing Gear Systems Committee), which meets twice a year, serves as a useful forum for discussion on landing gear issues and development. A current listing of documents produced and maintained by this committee appears in the appendix.
Author: Publisher: ISBN: Category : Aircraft Languages : en Pages : 86
Book Description
The ability to accurately predict the dynamic response of an aircraft while it is operating in the taxi mode depends, in part on the correct modeling of the dynamic characteristics of the landing gear system. Traditionally, landing gear have been designed to absorb landing impact ('shock absorber') and their characteristics during periodic, oscillatory response ('spring') have been considered as secondary. With the increased emphasis on the rough or damaged field taxi operation, there is a requirement to determine the best methods for modeling the gear system. This report documents a brief review of the state of the art of gear modeling. A study was then conducted to evaluate important model parameters, using a simple cantilevered gear computer simulation. Also included is the development of a technique for the experimental determination of important gear system parameters. (Author).
Author: National Aeronautics and Space Administration (NASA) Publisher: Createspace Independent Publishing Platform ISBN: 9781721181285 Category : Languages : en Pages : 34
Book Description
One of the problems facing the aircraft community is landing gear dynamics, especially shimmy and brake-induced vibration. Shimmy and brake-induced vibrations can lead to accidents due to excessive wear and shortened life of gear parts and contribute to pilot and passenger discomfort. To increase understanding of these problems, a literature survey was performed. The major focus is on work from the last ten years. Some older publications are included to understand the longevity of the problem and the background from earlier researchers. The literature survey includes analyses, testing, modeling, and simulation of aircraft landing gear; and experimental validation and characterization of shimmy and brake-induced vibration of aircraft landing gear. The paper presents an overview of the problem, background information, and a history of landing gear dynamics problems and solutions. Based on the survey an assessment and recommendations of the most critically needed enhancements to the state of the art will be presented. The status of Langley work contributing to this activity will be given. Pritchard, Jocelyn I. Langley Research Center NASA/TM-1999-209143, NAS 1.15:209143, ARL-TR-1976, L-17840
Author: Norman S. Currey Publisher: AIAA ISBN: 9781600860188 Category : Airplanes Languages : en Pages : 394
Book Description
This is the only book available today that covers military and commercial aircraft landing gear design. It is a comprehensive text that will lead students and engineers from the initial concepts of landing gear design through final detail design. The book provides a vital link in landing gear design technology from historical practices to modern design trends, and it considers the necessary airfield interface with landing gear design. The text is backed up by calculations, specifications, references, working examples.
Author: Robert Kyle Schmidt Publisher: SAE International ISBN: 0768099420 Category : Technology & Engineering Languages : en Pages : 1092
Book Description
The aircraft landing gear and its associated systems represent a compelling design challenge: simultaneously a system, a structure, and a machine, it supports the aircraft on the ground, absorbs landing and braking energy, permits maneuvering, and retracts to minimize aircraft drag. Yet, as it is not required during flight, it also represents dead weight and significant effort must be made to minimize its total mass. The Design of Aircraft Landing Gear, written by R. Kyle Schmidt, PE (B.A.Sc. - Mechanical Engineering, M.Sc. - Safety and Aircraft Accident Investigation, Chairman of the SAE A-5 Committee on Aircraft Landing Gear), is designed to guide the reader through the key principles of landing system design and to provide additional references when available. Many problems which must be confronted have already been addressed by others in the past, but the information is not known or shared, leading to the observation that there are few new problems, but many new people. The Design of Aircraft Landing Gear is intended to share much of the existing information and provide avenues for further exploration. The design of an aircraft and its associated systems, including the landing system, involves iterative loops as the impact of each modification to a system or component is evaluated against the whole. It is rare to find that the lightest possible landing gear represents the best solution for the aircraft: the lightest landing gear may require attachment structures which don't exist and which would require significant weight and compromise on the part of the airframe structure design. With those requirements and compromises in mind,The Design of Aircraft Landing Gear starts with the study of airfield compatibility, aircraft stability on the ground, the correct choice of tires, followed by discussion of brakes, wheels, and brake control systems. Various landing gear architectures are investigated together with the details of shock absorber designs. Retraction, kinematics, and mechanisms are studied as well as possible actuation approaches. Detailed information on the various hydraulic and electric services commonly found on aircraft, and system elements such as dressings, lighting, and steering are also reviewed. Detail design points, the process of analysis, and a review of the relevant requirements and regulations round out the book content. The Design of Aircraft Landing Gear is a landmark work in the industry, and a must-read for any engineer interested in updating specific skills and students preparing for an exciting career.
Author: Robert Kyle Schmidt Publisher: SAE International ISBN: 0768099439 Category : Technology & Engineering Languages : en Pages : 1092
Book Description
The aircraft landing gear and its associated systems represent a compelling design challenge: simultaneously a system, a structure, and a machine, it supports the aircraft on the ground, absorbs landing and braking energy, permits maneuvering, and retracts to minimize aircraft drag. Yet, as it is not required during flight, it also represents dead weight and significant effort must be made to minimize its total mass. The Design of Aircraft Landing Gear, written by R. Kyle Schmidt, PE (B.A.Sc. - Mechanical Engineering, M.Sc. - Safety and Aircraft Accident Investigation, Chairman of the SAE A-5 Committee on Aircraft Landing Gear), is designed to guide the reader through the key principles of landing system design and to provide additional references when available. Many problems which must be confronted have already been addressed by others in the past, but the information is not known or shared, leading to the observation that there are few new problems, but many new people. The Design of Aircraft Landing Gear is intended to share much of the existing information and provide avenues for further exploration. The design of an aircraft and its associated systems, including the landing system, involves iterative loops as the impact of each modification to a system or component is evaluated against the whole. It is rare to find that the lightest possible landing gear represents the best solution for the aircraft: the lightest landing gear may require attachment structures which don't exist and which would require significant weight and compromise on the part of the airframe structure design. With those requirements and compromises in mind,The Design of Aircraft Landing Gear starts with the study of airfield compatibility, aircraft stability on the ground, the correct choice of tires, followed by discussion of brakes, wheels, and brake control systems. Various landing gear architectures are investigated together with the details of shock absorber designs. Retraction, kinematics, and mechanisms are studied as well as possible actuation approaches. Detailed information on the various hydraulic and electric services commonly found on aircraft, and system elements such as dressings, lighting, and steering are also reviewed. Detail design points, the process of analysis, and a review of the relevant requirements and regulations round out the book content. The Design of Aircraft Landing Gear is a landmark work in the industry, and a must-read for any engineer interested in updating specific skills and students preparing for an exciting career.
Author: Jan Robert Wright Publisher: John Wiley & Sons ISBN: 047085846X Category : Technology & Engineering Languages : en Pages : 559
Book Description
Aeroelastic phenomena arising from the interaction of aerodynamic, elastic and inertia forces, and the loads resulting from flight / ground manoeuvres and gust / turbulence encounters, have a significant influence upon aircraft design. The prediction of aircraft aeroelastic stability, response and loads requires application of a range of interrelated engineering disciplines. This new textbook introduces the foundations of aeroelasticity and loads for the flexible aircraft, providing an understanding of the main concepts involved and relating them to aircraft behaviour and industrial practice. This book includes the use of simplified mathematical models to demonstrate key aeroelastic and loads phenomena including flutter, divergence, control effectiveness and the response and loads resulting from flight / ground manoeuvres and gust / turbulence encounters. It provides an introduction to some up-to-date methodologies for aeroelastics and loads modelling. It lays emphasis on the strong link between aeroelasticity and loads. It also includes provision of MATLAB and SIMULINK programs for the simplified analyses. It offers an overview of typical industrial practice in meeting certification requirements.
Author: A-5 Aerospace Landing Gear Systems Committee
Author: Jocelyn I. Pritchard
Author: Gordon Westly Davidson
Author: Robert Kyle Schmidt
Author: 
Author: National Aeronautics and Space Administration (NASA)
Author: Norman S. Currey
Author: Robert Kyle Schmidt
Author: Robert Kyle Schmidt
Author: Jan Robert Wright