by Sonny T. Chai and William H. Mason
MAD Center Report: MAD 96-09-01, September 1996
Supported by NASA Ames Research Center under Grant NAG-2-919
Multidisciplinary Analysis and Design Center
for Advanced Vehicles
Virginia Polytechnic Institute and State University
Blacksburg, Virginia, 24061-0203
Abstract
The design of the landing gear is one of the more fundamental aspects of aircraft design. The design and integration process encompasses numerous engineering disciplines, e.g., structures, weights, runway design and economics, and has become extremely sophisticated in the last few decades. Although the design process is well-documented, it is not available in an integrated design methodology that can be used within an automated environment. The process remains a key responsibility of the configuration designer and is largely experience-based and graphically-oriented. However, as industry and government try to incorporate multidisciplinary design optimization (MDO) methods in the conceptual design phase, the need for a more systematic procedure has become apparent.
The MDO-capable design methodology described in this report is focused on providing the conceptual designer with tools to help automate the disciplinary analyses, i.e., geometry, kinematics, flotation, and weight. The methods were developed by studying available documented design procedures and analyses together with an industrial survey. We then used our approach to study advanced large subsonic transports. The resulting methodology is available in the form of codes that can be used in existing MDO programs.
Electronic Version
This report is available electronically as a series of Adobe Acrobat files. The Adobe Acrobat reader is widely available for free, and is in theory platform independent. The report is provided in a format assuming it will be copied in a front and back style (meaning that there a few blank pages to start key sections on add numbered pages).
The front part of the report is available as a single pdf file (33k) containing: (Revised April 1, 1997)
The Software: Codes and data sets
Landing gear configuration selection
flotation analysis
Constraint violations determination
Landing gear weight estimation
Acknowledgments
This work would not have been possible without the support of NASA Ames Research Center, under grant NAG-2-919. Paul Gelhausen and Shahab Hassan served as technical monitors. At Virginia Tech Dr. Eric R. Johnson assisted with the analysis supporting the weight estimation methodology and Dr. Antonio A. Trani helped us develop the pavement thickness requirements analysis. We also were helped by a number of other individuals, including Mr. Bill Perrella and Mr. John Rice at the Federal Aviation Administration, Mr. Edward Gervais, Mr. Jerry Kileer, Mr. Bob Nielson, Mr. Dave Nielson, Mr. Scott Perkins, and Mr. John Potter at Boeing Commercial Aircraft Group, Mr. Al Kernik at McDonnell Douglas, Mr. Gene Stuczynski at Cleveland Pneumatic, Mr. Bill Luce at Menasco Aerosystems, Mr. Derek Duxbury at British Aerospace, Mr. Ron Olds, Mr. Dean Peters, and Mr. Paul Snyder at B.F. Goodrich, Mr. Joe Pacuit at the Tire and Rim Association, Inc., Mr. Richard Vandame of the SAE A-5 Committee, Mr. James Gallivan at United Airlines, and Mr. Steve Lydon at Northwest Airlines. We appreciate their assistance and valuable input during the initial industry survey. Last but not least, we acknowledge Mr. Nathan Kirschbaum at Virginia Tech for his insight into landing gear design considerations at the aircraft conceptual design stage.