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Air Transportation Systems Engineering

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Type: NoteInstitute: JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY Downloads: 26Views: 316Uploaded: 8 months agoAdd to Favourite

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Jntu Heroes
LECTURE NOTES ON AIR TRANSPORTATION SYSTEMS III B. Tech I semester (JNTUH-R13) AERONAUTICAL ENGINEERING
UNIT-1 AVIATION INDUSTRY & ITS REGULATORY AUTHORITIES AN INTRODUCTION TO AIR TRANSPORT AVIATION: AN OVERVIEW INTRODUCTION In a short span of 100 years, we have gone from making a few test flights to orbiting celestial bodies, from sliding along sand dunes to spanning oceans, from performing feats of isolated daring to depending on aviation in our everyday lives. Speeds have increased a thousand fold, as have altitude and range capability. No longer is the sky the limit. Ahead lie risks and rewards as vast as space itself. We have the promise of new airliners that fly with greater fuel efficiency, of huge air freighters that move the nation‘s goods, of an expanding general aviation fleet, and of the peaceful uses of space for exploration and research. THE AEROSPACE INDUSTRY The aerospace industry includes those firms engaged in research, development, and manufacture of all of the following: aerospace systems, including manned and unmanned aircraft; missiles, space-launch vehicles, and spacecraft; propulsion, guidance, and control units for all of the foregoing; and a variety of airborne and ground-based equipment essential to the testing, operation, and maintenance of flight vehicles. Virtually all of the major firms in the aerospace industry are members of the Aerospace Industries Association (AIA) or the General Aviation Manufacturers Association (GAMA). Founded in 1919 and based in Washington, D.C., the AIA is a trade association representing the nation‘s manufacturers of commercial, military, and business aircraft, helicopters, aircraft engines, missiles, spacecraft, and related components and equipment. GAMA, also based in Washington, D.C., is the trade association that represents the interests of manufacturers of light aircraft and component parts. As the 21st century began, approximately two-thirds of the aerospace industry‘s output was bought by the federal government. During the past two decades, this figure has ranged as high as 74 percent. At the same time, the aerospace industry is the world‘s largest producer of civil aircraft and equipment. Roughly 6 out of every 10 transports operating with the world‘s civil airlines are of U.S. manufacture, and in addition, the industry turns out several thousand civil helicopters and general aviation planes yearly. These facts underline the unique status of the aerospace industry. Its role as principal developer and producer of defence, space, and other government required systems in large measure dictates the industry‘s size, structure, and product line. Because it operates under federal government procurement policies and practices, the industry is subject to controls markedly different from those of the commercial marketplace. But the aerospace industry is also a commercial entity, and it must compete in the civil market for economic and human resources with other industries less featured by government constraints. Its dual nature as government and commercial supplier makes the aerospace industry particularly important to the national interest. Its technological capabilities influence national security, foreign policy, the space program, and other national goals. Also, the efficacy of the national air transportation system depends to considerable degree on the quality and performance of equipment produced for the airlines and the airways operators. Naturally, such an industry is vital to the U.S. economy, especially in the following areas: 1. Trade balance. The excellence of U.S. aerospace products has created strong demand abroad, with the result that the industry consistently records a large international trade surplus.
2. Employment. Despite several years of decline in number of workers, the aerospace industry remains one of the nation‘s largest manufacturing employers. 3. Research and development. The industry conducts more research and development (R & D) than any other industry, and R & D is a major long-term determinant of national economic growth. 4. Impact on other industries. A great many new aerospace-related products and processes have spun off from the initial aerospace requirement and have provided value to other industries, both in sales and in productive efficiency. In addition, the aerospace industry is a largescale user of other industries‘ goods and services: it has been estimated that for every 100 aerospace jobs created, another 73 are created in other industries. Each of these factors represents a significant contribution to the U.S. economy; collectively, they elevate aerospace to a key position among the nation‘s major industries. Characteristics of the Industry The history of the aerospace industry has been a saga of continuing adjustment to changing national policy and economic conditions. Since 1960, fluctuating government demands and a variety of international events have teamed up to produce a roller -coaster like sales curve: up to a peak, down to a valley. Over the years, the industry‘s operations have become increasingly complex, with each increment of complexity heightening the industry‘s problems in adapting to change. Today, the industry‘s unique characteristics make the adaptive process extraordinarily difficult. An understanding of the difficulties is best promoted by an explanation of how the industry has been transformed in the past quarter of a century. Prior to 1950, the industry was relatively unsophisticated. Its product line was entirely aeronautical—aircraft, engines, propellers, avionic components, and accessories. Long run production of many airplane types was the order of the day. The labour force, during the postWorld War II retrenchment period, was less than one-fi_h of the later peak. Three-fourths of the workers were moderately skilled production workers. R & D was an essential prelude to production, but the subsonic aircraft then being built were less demanding of technological advance, and R & D represented a considerably less significant portion of the total workload than it does today. The transformation began in the early 1950s with the production of the jet-powered supersonic military airplane, which brought about across-the-board changes in the industry new types of engines, totally different airframes, different on-board equipment, new tooling and facilities, and, most of all, a vastly greater degree of complexity in products and the methods employed in producing them. New-airplane performance dictated that far greater emphasis be placed on R & D. The combination of R & D and product complexity required a major shift in the composition of the work force to include ever-increasing numbers of scientists, engineers, and highly skilled technicians. All of these changes resulted in increased emphasis on an ever more sophisticated managerial process. While the industry was adjusting to these changes, it inherited a new responsibility: development and production of guided missiles, particularly long-range ballistic weapons. Then came another major change: the application of turbine power to commercial airliners, whose resemblance to military jets ended with their propulsion systems. The need to transport large numbers of people at high subsonic speeds and multi mile altitudes involved a further modification of the industry‘s methods. Finally, in the late 1950s, the industry was assigned
still another responsibility: fabrication of equipment to meet the nation‘s goals in space exploration. Each of these changes compounded the need for change in the entire industry—more R & D, greater product complexity, more personnel per unit produced, higher skill levels in the work force, longer program development time, and greater need for new facilities with only singleprogram utility because of their specialized natures. Such changes contributed to higher costs of the end products, and the demand in the 1960s and 1970s for still more advanced aerospace systems further escalated both the rate of change and the costs. In defence output, cost—together with the greater capability of the individual system influenced a trend away from volume production and toward tailored manufacture of fewer types of weapons and fewer numbers of each type. A half-century of evolution has le_ the aerospace industry with a set of characteristics unique in U.S. manufacturing: 1. Performance demands for new systems require continual advancement of the technological frontier, which in turn involves unusual degrees of uncertainty and risk. 2. Because the government is the principal customer, the product line is subject to revisions in program levels occasioned by changing requirements and funding availability. 3. Equipment that challenges the state of the art is necessarily costly, the more so because requirements generally dictate short production runs, negating the economies of large-scale production. 4. Technologically demanding programs require personnel emphasis in the higher skill levels. Hence, labor input per unit of output is substantially larger than in other manufacturing industries. 5. The combination of technological uncertainty and long lead times, o_en 7–10 years and frequently longer, between program initiation and completion, makes advance estimation of costs particularly difficult. 6. Because there are few customers and relatively few programs, competition for the available business is intense. 7. All of these characteristics contribute to exceptional demand for industry capital, yet profits as a percentage of sales are consistently well below the average for all manufacturing industries. Economic Profile of the Industry The aerospace industry is composed of about 60 major firms operating some 1,000 facilities, backed by thousands of subcontractors, vendors, and suppliers. The principal product line aircraft, missiles, space systems and related engines, and parts and equipment is characterized by high performance and high reliability, and hence high technology and high unit value. Activity, as measured by sales volume, focuses on aircraft, both civil and military, which account for almost 55 percent of the industry‘s workload. Missile systems represent about 6

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