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Maddalon, D. V.

Publications and source records attributed to Maddalon, D. V..

At least 37 records · Page 2
All sourcesNASA NTRSDOE OSTI
NASA NTRS1982

Laminar flow control, 1976 - 1982: A selected annotated bibliography

Laminar Flow Control technology development has undergone tremendous progress in recent years as focused research efforts in materials, aerodynamics, systems, and structures have begun to pay off. A virtual explosion in the number of research papers published on this subject has occurred since interest was first stimulated by the 1976 introduction of NASA's Aircraft Energy Efficiency Laminar Flow Control Program. The purpose of this selected bibliography is to list available, unclassified laminar flow (both controlled and natural) research completed from about 1975 to mid 1982. Some earlier pertinent reports are included but listed separately in the Appendix. Reports listed herein emphasize aerodynamics and systems studies, but some structures work is also summarized. Aerodynamic work is mainly limited to the subsonic and transonic sped regimes. Because wind-tunnel flow qualities, such as free stream disturbance level, play such an important role in boundary-layer transition, much recent research has been done in this area and it is also included.

Tuttle, M. H.↗
NASA NTRS1982

NASA research on viscous drag reduction

Research on natural laminar flow, laminar flow control by suction, and turbulent drag reduction is discussed. Preliminary results suggest that a significant amount of natural laminar flow can be achieved on small, straight wing airplanes. On larger, swept wing aircraft, laminar flow control by distributed suction is expected to result in significant fuel savings. The area over which laminar flow control is applied depends on tradeoffs involving structural complexity, maintenance, and cost. Several methods of reducing turbulent skin friction by altering the turbulence structure itself have shown promise in exploratory testing. The status of these technologies and the benefits of applying them to future aircraft are reviewed.

Petersen, R. H.↗
NASA NTRS1982

Multibody transport concept

Two baseline aircraft are configured in this study. The multibody aircraft has two fuselage bodies located at approximately 28% wing semispan. The single-body aircraft is configured in such a way as to provide a reference base with which the multibody aircraft can be compared. The aircraft are sized to provide the lowest direct operating cost configuration when transporting 771,620 lbs. over a distance of 3,500 nautical miles at a cruise speed of Mach 0.80. The aircraft are assumed to operate in the years 1990-1995, thus allowing for the incorporation of those technologies expected to be mature and available for production usage in 1985. In comparison with the single-body aircraft, the two-body aircraft shows reductions of 8.9% in wing weight, 7.7% in structural weight, 13.5% in block fuel weight, and 11.3% in direct operating cost.

Moore, J. W.↗
NASA NTRS1982

NASA research on viscous drag reduction

Current NASA research points toward exciting opportunities for large reductions in viscous drag. Research is underway on natural laminar flow, laminar flow control by suction, and turbulent drag reduction. Preliminary results suggest that a significant amount of natural laminar flow can be achieved on small, straight-wing airplanes. On larger, swept-wing aircraft, laminar flow control by distributed suction is expected to result in significant fuel savings. The area over which laminar flow control is applied depends on tradeoffs involving structural complexity, maintenance, and cost. Several methods of reducing turbulent skin friction by altering the turbulence structure itself have shown promise in exploratory testing. This paper reviews the status of these technologies and indicates the benefits of applying them to future aircraft.

Petersen, R. H.↗
NASA NTRS1981

US and USSR Military Aircraft and Missile Aerodynamics 1970-1980. A selected, annotated bibliography, volume 1

The purpose of this selected bibliography (281 citations) is to list available, unclassified, unlimited publications which provide aerodynamic data on major aircraft and missiles currently used by the military forces of the United States of America and the Union of Soviet Socialist Republics. Technical disciplines surveyed include aerodynamic performance, static and dynamic stability, stall-spin, flutter, buffet, inlets nozzles, flap performance, and flying qualities. Concentration is on specific aircraft including fighters, bombers, helicopters, missiles, and some work on transports, which are or could be used for military purposes. The bibliography is limited to material published from 1970 to 1980. The publications herein illustrate many of the types of aerodynamic data obtained in the course of aircraft development programs and may therefore provide some guidance in identifying problems to be expected in the conduct of such work. As such, this information may be useful in planning future research programs.

Tuttle, M. H.↗
NASA NTRS1980

Computer programs for estimating civil aircraft economics

Computer programs for calculating airline direct operating cost, indirect operating cost, and return on investment were developed to provide a means for determining commercial aircraft life cycle cost and economic performance. A representative wide body subsonic jet aircraft was evaluated to illustrate use of the programs.

Maddalon, D. V.↗
NASA NTRS1979

Potential applications of advanced aircraft in developing countries

Air transportation concepts for movement of cargo in developing countries are reviewed using aicraft which may appear in the future. For certain industrial applications, including mining and forestry, the relative costs of doing the job using different types of aircraft are compared with surface transportation systems. Two developing countries, Brazil and Indonesia, were taken as examples to determine what impact they might have on the aircraft markets of the future. Economic and demographic data on developing countries in general, and Brazil and Indonesia in particular, are reviewed. The concept of an industrial city in a remote area developed around an airport is discussed. It is noted that developing areas generally lack extensive surface transportation systems and that an air transportation system can be implemented in a relatively short time. A developing nation interested in rapid expansion may thus find the role of air cargo far more important than has been true in developed nations. Technological developments which may dramatically increase the performance of agricultural aircraft are also reviewed.

Maddalon, D. V.↗
NASA NTRS1978

Potential applications of advanced aircraft in developing countries

An investigation sponsored by NASA indicates that air transportation can play an important role in the economic progress of developing countries. By the turn of the century, the rapid economic growth now occurring in many developing countries should result in a major redistribution of the world's income. Some countries now classified as 'developing' will become 'developed' and are likely to become far more important to the world's civil aviation industry. Developing countries will be increasingly important buyers of conventional subsonic long-haul jet passenger aircraft but not to the point of significant influence on the design or technological content of future aircraft of this type. However, the technological content of more specialized aircraft may be influenced by developing country requirements and reflected in designs which fill a need concerning specialized missions, related to short-haul, low-density, rough runways, and natural resource development.

Maddalon, D. V.↗
NASA NTRS1978

Estimating airline operating costs

A review was made of the factors affecting commercial aircraft operating and delay costs. From this work, an airline operating cost model was developed which includes a method for estimating the labor and material costs of individual airframe maintenance systems. The model, similar in some respects to the standard Air Transport Association of America (ATA) Direct Operating Cost Model, permits estimates of aircraft-related costs not now included in the standard ATA model (e.g., aircraft service, landing fees, flight attendants, and control fees). A study of the cost of aircraft delay was also made and a method for estimating the cost of certain types of airline delay is described.

Maddalon, D. V.↗
NASA NTRS1978

Estimating Airline Operating Costs

The factors affecting commercial aircraft operating and delay costs were used to develop an airline operating cost model which includes a method for estimating the labor and material costs of individual airframe maintenance systems. The model permits estimates of aircraft related costs, i.e., aircraft service, landing fees, flight attendants, and control fees. A method for estimating the costs of certain types of airline delay is also described.

Maddalon, D. V.↗
NASA NTRS1976

Foreign civil aviation competition: 1976 summary and implications

A summary assessment is made of foreign civil aviation as it relates to the posture of the United States civil aviation industry. Major findings include: (1) Main competitors - European Economic Community (EEC) and Union of Soviet Socialist Republics (USSR). (2) Largest commercial market - Transport aircraft. (3) Current market status and projections - U.S. currently dominates the civil aviation market but foreign markets show greater growth trends. (4) Competitive comparisons - Status comparisons are made in technology (aerodynamics, structures and materials, propulsion, avionics, systems, design coordination, and manufacturing); production runs; marketing; and postsales support. The U.S. generally leads except in aerodynamics and propulsion. (5) Multinational ventures - Joint U.S. industry/foreign government development of advanced technology engines is well developed; airframe industry discussions are now underway. (6) Implications - Although the U.S., is currently preeminent in most areas, this may be only a temporary condition. Past U.S. success in aviation has provided many benefits to the nation. These benefits may be lost.

Alford, W. J., Jr.↗
NASA NTRS1976

Energy and Economic Trade Offs for Advanced Technology Subsonic Aircraft

Changes in future aircraft technology which conserve energy are studied, along with the effect of these changes on economic performance. Among the new technologies considered are laminar-flow control, composite materials with and without laminar-flow control, and advanced airfoils. Aircraft design features studied include high-aspect-ratio wings, thickness ratio, and range. Engine technology is held constant at the JT9D level. It is concluded that wing aspect ratios of future aircraft are likely to significantly increase as a result of new technology and the push of higher fuel prices. Composite materials may raise aspect radio to about 11 to 12 and practical laminar flow-control systems may further increase aspect ratio to 14 or more. Advanced technology provides significant reductions in aircraft take-off gross weight, energy consumption, and direct operating cost.

Maddalon, D. V.↗
NASA NTRS1976

Energy and economic trade offs for advanced technology subsonic aircraft

Changes in future aircraft technology which conserve energy are studied, along with the effect of these changes on economic performance. Among the new technologies considered are laminar-flow control, composite materials with and without laminar-flow control, and advanced airfoils. Aircraft design features studied include high-aspect-ratio wings, thickness ratio, and range. Engine technology is held constant at the JT9D level. It is concluded that wing aspect ratios of future aircraft are likely to significantly increase as a result of new technology and the push of higher fuel prices. Whereas current airplanes have been designed for AR = 7, supercritical technology and much higher fuel prices will drive aspect ratio to the AR = 9-10 range. Composite materials may raise aspect ratio to about 11-12 and practical laminar flow-control systems may further increase aspect ratio to 14 or more. Advanced technology provides significant reductions in aircraft take-off gross weight, energy consumption, and direct operating cost.

Maddalon, D. V.↗
NASA NTRS1974

Rating aircraft on energy

Questions concerning the energy efficiency of aircraft compared to ground transport are considered, taking into account as energy intensity the energy consumed per passenger statute mile. It is found that today's transport aircraft have an energy intensity potential comparable to that of ground modes. Possibilities for improving the energy density are also much better in the case of aircraft than in the case of ground transportation. Approaches for potential reductions in aircraft energy consumption are examined, giving attention to steps for increasing the efficiency of present aircraft and to reductions in energy intensity obtainable by the introduction of new aircraft utilizing an advanced technology. The use of supercritical aerodynamics is discussed along with the employment of composite structures, advances in propulsion systems, and the introduction of very large aircraft. Other improvements in fuel economy can be obtained by a reduction of skin-friction drag and a use of hydrogen fuel.

Maddalon, D. V.↗
NASA NTRS1974

Air transportation - Energy cost-effective or not

Current technology aircraft have energy intensities comparable to ground transport modes. Operational changes can further improve their relative energy performance. Wide-body aircraft have already significantly improved fleet energy intensity and will continue to do so as they become more predominant. This is reflected in the 1972 fleet-wide energy intensity data which show both the domestic and international carriers at the lowest jet aircraft intensity levels ever attained. Technological improvements decreased the energy requirements of wide-body aircraft while also significantly reducing aircraft noise and pollution emission levels. Load factor is the most significant parameter affecting existing aircraft energy intensity and therefore should be raised. Fuel scarcity is now forcing such a change.

Maddalon, D. V.↗