This paper presents a brief summary of the airplane landing gear research underway at NASA. The technology areas include: ground handling simulator, antiskid braking systems, space shuttle nose-gear shimmy, active control landing gear, wire brush skid landing gear, air cushion landing systems, tire/surface friction characteristics, tire mechanical properties, tire-tread materials, powered wheels for taxiing, and crosswind landing gear. This paper deals mainly with the programs on tire-tread materials, powered wheel taxiing, air cushion landing systems, and crosswind landing gear research with particular emphasis on previously unreported results of recently completed flight tests. Work in the remaining areas is only mentioned. Fisher, B. D. and Sleeper, R. K. and Stubbs, S. M. Langley Research Center NASA-TM-78679 RTOP 505-08-33-12...
The Lockheed Blackbirds hold a unique place in the development of aeronautics. In their day, the A-12, YF-12, M-21, D-21, and SR-71 variants outperformed all other jet airplanes in terms of altitude and speed. Now retired, they remain the only production aircraft capable of sustained Mach 3 cruise and operational altitudes above 80,000 feet.This is the first book to address the technical aspects of these incredible aircraft. The author describes the design evolution of the Blackbird, from the Archangel to the Senior Crown (the Air Force's SR-71.) He describes in detail the construction and materials challenges faced by Lockheed, as well as the Blackbird's performance characteristics and capabilities.A NASA historian, the author describes NASA's role in using the aircraft as a flying laboratory to collect data on materials, structures, loads, heating, aerodynamics, and performance for high-speed aircraft. The reader will benefit from the technical and programmatic lessons learned.This volume was produced in cooperation with the National Aeronautics and Space Administration.
Full color publication. This document has been produced and updated over a 21-year period. It is intended to be a handy reference document, basically one page per flight, and care has been exercised to make it as error-free as possible. This document is basically "as flown" data and has been compiled from many sources including flight logs, flight rules, flight anomaly logs, mod flight descent summary, post flight analysis of mps propellants, FDRD, FRD, SODB, and the MER shuttle flight data and inflight anomaly list. Orbit distance traveled is taken from the PAO mission statistics.
This document presents an approach for modeling and simulating landing gear systems. Specifically, a nonlinear model of an A-6 Intruder Main Gear is developed, simulated, and validated against static and dynamic test data. This model includes nonlinear effects such as a polytropic gas model, velocity squared damping, a geometry governed model for the discharge coefficients, stick-slip friction effects and a nonlinear tire spring and damping model. An Adams-Moulton predictor corrector was used to integrate the equations of motion until a discontinuity caused by a stick-slip friction model was reached, at which point, a Runga-Kutta routine integrated past the discontinuity and returned the problem solution back to the predictor corrector. Run times of this software are around 2 mins. per 1 sec. of simulation under dynamic circumstances. To validate the model, engineers at the Aircraft Landing Dynamics facilities at NASA Langley Research Center installed one A-6 main gear on a drop carriage and used a hydraulic shaker table to provide simulated runway inputs to the gear. Model parameters were tuned to produce excellent agreement for many cases. Daniels, James N. Langley Research Center...
The Apollo 11 Mission, primarily designed to land men on the Moon and return them safely to Earth, signaled a new phase of the manned space program. Based on the success of Apollo 11, the first of a series of missions designed for the systematic exploration of the Moon was successfully accomplished on Apollo 12. The fact that the Apollo 12 astronauts were able to achieve a pinpoint landing at a preselected site, and then spend an extended time on the lunar surface, graphically illustrates the rapid progress of the Apollo program. The Apollo 12 mission added significantly to man's knowledge of the Moon. The precise landing capability allowed the crew to accomplish a wide variety of preplanned tasks and paved the way for planning future missions to smaller, more selected landing areas with the possibility of significant scientific returns. The publication includes chapters on mission description, summary of scientific results, photographic summary of the Apollo 12 Mission, crew observations, passive seismic experiment, lunar surface magnetometer experiment, the solar-wind spectrometer experiment, suprathermal ion detector experiment (lunar ionosphere detector), cold cathode gage (lunar atmosphere detector), the solar-wind composition experiment, Apollo 12 multispectral photography experiment, preliminary geologic investigation of the Apollo 12 landing site, lunar surface closeup stereoscopic photography, preliminary examination of lunar samples, and preliminary results from Surveyor 3 analysis.
"Much has been written about the famous conflicts and battlegrounds of the East during the American Revolution. Perhaps less familiar, but equally important and exciting, was the war on the western frontier, where Ohio Valley settlers fought for the land they had claimed -- and for their very lives. George Rogers Clark stepped forward to organize the local militias into a united front that would defend the western frontier from Indian attacks. Clark was one of the few people who saw the importance of the West in the war effort as a whole, and he persuaded Virginia's government to lend support to his efforts. As a result Clark was able to cross the Ohio, saving that part of the frontier from further raids. Lowell Harrison captures the excitement of this vital part of American history while giving a complete view of George Rogers Clark's significant achievements. Lowell H. Harrison, is a professor emeritus of history at Western Kentucky University and is the author or co-author of numerous books, including Lincoln of Kentucky, A New History of Kentucky, and Kentucky's Governors."
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.
