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Mayer, N. J.

Publications and source records attributed to Mayer, N. J..

At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1983

1983 LTA technology assessment

Several aspects of LTA (lighter-than-air) technology development are reviewed. Technological developments of classical airships through 1974 are examined. A brief historical and technological summary of five specialized LTA equipment concepts is presented: metal-clad airships, free balloons, semibuoyant vehicles, high-altitude platforms, and tethered aerostats. Current LTA technology developments are reviewed with particular emphasis on VTOL airships capable of heavy lift and on long endurance types for coastal maritime patrol. Finally, the future prospects of LTA system development are considered with attention given to manned conventional and hybrid vehicles, tethered vehicles, and RPVs.

Ashford, R. L.↗
NASA NTRS1983

A study of dirigibles for use in the Peruvian Selva Central region

A study to evaluate dirigibles as transport vehicles in the mainly undeveloped and heavily forested Selva Central region of Peru is discussed. The basic requirements for dirigible service in the region are described, including those pertaining to cargoes and routes, airports, weather conditions, ground facilities, operations and maintenance base, hangars, ballast, and helium supply. Dirigible types, sizes, and economics were analyzed, and the analytical methods and results are reported. Total costs are determined and compared with those for other aircraft. It is concluded that dirigibles can be used as transport in the Selva Central and that conventional dirigibles in normal operation will require expansion of exisiting airfields. Conventional dirigibles are more economical as their size increases and are cost effective compared to selected aircraft.

Mayer, N. J.↗
NASA NTRS1982

A study of dirigibles for use in the Peruvian Selva Central Region

The potential for dirigibles as transports in the Selva Central region of Peru was evaluated by means of a mission and economic analysis. A total requirement to transport over 19 million tons (t) of agricultural produce, lumber, and meat was projected by the year 2004. A primary route involving zones for loading and delivering this cargo was identified. Although dirigibles are capable of short field operation, all existing airfields must be enlarged in width to allow for all conditions of wind and weather and to provide space for overnight mooring. A maintenance base and operations headquarters, complete with hangar and other service facilities would be required. The quantities of cargo to be carried establish requirements for fleets of dirigibles of various sizes and capacities. Cargo capacities of 5 to 100 tons were identified. Fleet sizes up to 106 dirigibles (in 20 t capacities) would be required. Dirigibles were assumed to be of the nonrigid type except in the 100 t category for which rigid characteristics were assumed. A method of determining dirigible costs was developed. The values derived were then applied to an economic analysis to determine initial investment and operating costs. It was found that larger dirigibles of approximately 20 t capacities or higher could offer significant cost benefits over airplanes, provided cruise speeds were higher than 100 km/hr.

Mayer, N. J.↗
NASA NTRS1982

A study of dirigibles for use in the Peruvian Selva Central region

The potential for dirigibles as transports in the Selva Central region of Peru was evaluated by means of a mission and economic analysis. A total requirement to transport over 19 million tons (t) of agricultural produce, lumber and meat was projected by the year 2004. A primary route involving zones for loading and delivering this carbo was identified. Although dirigibles are capable of short field operation, all existing airfields must be enlarged in width to allow for all conditions of wind and weather and to provide space for overnight mooring. A maintenance base and operations headquarters, complete with hangar and other service facilities would be required. The quantities of cargo capacities of 5 to 100 tons were identified. Fleet sizes up to 106 dirigibles (in 20 t capacities) would be required. Dirigibles were assumed to be of the nonrigid type except in the 100 t category for which rigid characteristics were assumed. A method of determining dirigible costs was developed. The values derived were then applied to an economic analysis to determine initial investment and operating costs. It was found that larger dirigibles of approximately 20 t capacities or higher could offer significant cost benefits over airplanes, provided cruise speeds were higher than 100km/hr.

Mayer, N. J.↗
NASA NTRS1981

The balloon and the airship technological heritage

The balloon and the airship are discussed with emphasis on the identification of commonalities and distinctions. The aerostat technology behind the shape and structure of the vehicles is reviewed, including a discussion of structural weight, internal pressure, buckling, and the development of a stable tethered balloon system. Proper materials for the envelope are considered, taking elongation and stress into account, and flight operation and future developments are reviewed. Airships and tethered balloons which are designed to carry high operating pressure with low gas loss characteristics are found to share similar problems in low speed flight operations, while possessing interchangeable technologies.

Mayer, N. J.↗
NASA NTRS1981

1981 LTA technology assessment - Past and present

A four-part presentation is made of (1) lessons learned from the design and operation of the 'classic' airships of the 1920s and 30s, with respect to such issues as construction, propulsion, control, instrumentation, ground handling, habitability, aerodynamics, and structure and construction; (2) lessons learned from the development of such specialized lighter-than-air (LTA) concepts as metal-clad airships, semi-buoyant lifting bodies, experimental, sport and commercial free balloons, high-altitude platforms, and tethered aerostats; (3) the current status of LTA technology in various countries, with emphasis on significant developments in configuration, dynamics, control, structures, materials, and propulsion; and (4) a projection of future trends. It is concluded that socio-economic factors will strongly influence and encourage LTA development in the 1990s.

Ashford, R. L.↗
NASA NTRS1981

Current LTA technology developments

Lighter-than-air aircraft (LTA) developments and research in the United States and other countries are reviewed. The emphasis in the U.S. is on VTOL airships capable of heavy lift, and on long endurance types for coastal maritime patrol. Design concepts include hybrids which combine heavier-than-air and LTA components and characteristics. Research programs are concentrated on aerodynamics, flight dynamics, and control of hybrid types.

Mayer, N. J.↗
NASA NTRS1981

Current developments lighter than air systems

Lighter than air aircraft (LTA) developments and research in the United States and other countries are reviewed. The emphasis in the U.S. is on VTOL airships capable of heavy lift, and on long endurance types for coastal maritime patrol. Design concepts include hybrids which combine heavier than air and LTA components and characteristics. Research programs are concentrated on aerodynamics, flight dynamics, and control of hybrid types.

Mayer, N. J.↗
NASA NTRS1979

Large lighter-than-air vehicles

The background of experience and the results achieved in building large airships are discussed. Two current applications are identified. These are in heavy vertical lift and in long endurance patrol. The most promising concepts for these missions include hybrid combinations of helicopters and aerostats and more conventional rigid types. These new approaches will require some technology development in aerodynamics and structures, but all vehicles will benefit from application of modern methods and materials.

Mayer, N. J.↗
NASA NTRS1979

A summary of lighter-than-air technology development and applications in the United States

Recent studies indicate the promise of advanced LTA vehicles that can carry heavy loads and be capable of vertical takeoff and landing. Such airships may be combinations of aerostats and helicopters or modern versions of more conventional aircraft. These latter types would not be competitive with high speed modern jet air transports on established routes, but they would have a role in special situations and as long-endurance Naval and coastal surveillance aircraft. The most attractive and immediate market for modern airships in the field of short-range and heavy lift.

Mayer, N. J.↗
NASA NTRS1977

A review of lighter-than-air progress in the United States and its technological significance

Lighter-than-air craft for transportation and communications systems are discussed, with attention given to tethered balloons used to provide stable platforms for airborne surveillance equipment, freight-carrying balloons, manned scientific research balloons such as Atmosat, high-altitude superpressure aerostats employed in satellite communications systems, airport feeder airships, and naval surveillance airships. In addition, technical problems associated with the development of advanced aerostats, including the aerodynamics of hybrid combinations of large rotor systems and aerostat hulls, the application of composites to balloon shells, computer analyses of the complex geometrical structures of aerostats and propulsion systems for airships, are considered.

Mayer, N. J.↗
NASA NTRS1977

LTA - Recent developments

NASA-sponsored studies of existing and new LTA missions showed that airships looked very promising for some two dozen civil and military applications. These include surveillance of rural and urban areas, in the form of forest and police patrols; transport of very heavy large-volume maritime, industrial, and military payloads; coastal patrol and sea control; seismographic surveys; air pollution monitoring; and moving goods to remote areas; along with a number of less important but still attractive missions. A figure of merit of productivity (payload weight, ton moles per hour) was used to compare airships of various type and size. In each case, this criterion established an index of efficiency for evaluating not only conceptual approaches but also modes of flight. Some, in part unexpected, results of these studies are described.

Mayer, N. J.↗
NASA NTRS1975

LTA structures and materials technology

The state-of-the-art concerning structures and materials technology is reviewed. It is shown that many present materials developments resulting from balloon and aircraft research programs can be applied to new concepts in LTA vehicles. Both buoyant and semi-buoyant vehicles will utilize similar approaches to solving structural problems and could involve pressurized non-rigid and unpressurized rigid structures. System designs common to both and vital to structural integrity will include much of the past technology as well. Further research is needed in determination of structural loads, especially in future design concepts.

Mayer, N. J.↗
NASA NTRS1975

LTA structures and materials technology

The state-of-the-art concerning structures and materials technology is reviewed. It is shown that many present materials developments resulting from balloon and aircraft research programs can be applied to new concepts in LTA vehicles. Both buoyant and semi-buoyant vehicles utilize similar approaches to solving structural problems and could involve pressurized non-rigid and unpressurized rigid structures. System designs common to both and vital to structural integrity include much of the past technology as well. Further research is needed in determination of structural loads, especially in future design concepts.

Mayer, N. J.↗
NASA NTRS1974

Carbon composites in space vehicle structures

Recent developments in the technology of carbon or graphite filaments now provide the designer with greatly improved materials offering high specific strength and modulus. Besides these advantages are properties which are distinctly useful for space applications and which provide feasibility for missions not obtainable by other means. Current applications include major and secondary structures of communications satellites. A number of R & D projects are exploring carbon-fiber application to rocket engine motor cases, advanced antenna systems, and space shuttle components. Future system studies are being made, based on the successful application of carbon fibers for orbiting space telescope assemblies, orbital transfer vehicles, and very large deployable energy generation systems. Continued technology development is needed in analysis, material standards, and advanced structural concepts to exploit the full potential of carbon filaments in composite materials.

Mayer, N. J.↗
NASA NTRS1974

Civil aircraft

This study deals with aircraft material and structural requirements, advantages of composites, airframe and engine applications, design procedures, problem areas, and future trends in civil aircraft. The selection of materials and design of structure for any given component or part must be made not only on the basis of the mechanical and structural functions, but must also consider the operational and cost parameters for civil aircraft. Composites have caused the orientation to shift from a metal-based philosophy for design, where only incremental improvements could be anticipated, to one where substantial changes in design approaches are possible. Future designs are likely to include a combination of new approaches and composite materials.

Mayer, N. J.↗
NASA NTRS1973

Composite materials in space structures

The use of composite materials in space vehicle structures offers significant advantages in reduction of structural weight fractions and in obtaining improved dynamic characteristics. Recent studies and developments include inertial booms for scientific satellites, structural components for future space shuttle applications, and pressurized tanks. Future applications could include major portions of vehicle primary structures as well as many secondary structural components. A number of problems still exist regarding achievement of the objectives, including development of sufficient environmental data, reliable design techniques, and general user confidence. These will be attacked in future R&D programs.

Mayer, N. J.↗