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Butterfield, A. J.

Publications and source records attributed to Butterfield, A. J..

Concepts for manned lunar habitats

The design philosophy that will guide the design of early lunar habitats will be based on a compromise between the desired capabilities of the base and the economics of its development and implantation. Preferred design will be simple, make use of existing technologies, require the least amount of lunar surface preparation, and minimize crew activity. Three concepts for an initial habitat supporting a crew of four for 28 to 30 days are proposed. Two of these are based on using Space Station Freedom structural elements modified for use in a lunar-gravity environment. A third concept is proposed that is based on an earlier technology based on expandable modules. The expandable modules offer significant advantages in launch mass and packaged volume reductions. It appears feasible to design a transport spacecraft lander that, once landed, can serve as a habitat and a stand-off for supporting a regolith environmental shield. A permanent lunar base habitat supporting a crew of twelve for an indefinite period can be evolved by using multiple initial habitats. There appears to be no compelling need for an entirely different structure of larger volume and increased complexity of implantation.

Hypes, W. D.

Advanced-technology space station study: Summary of systems and pacing technologies

The principal system features defined for the Advanced Technology Space Station are summarized and the 21 pacing technologies identified during the course of the study are described. The descriptions of system configurations were extracted from four previous study reports. The technological areas focus on those systems particular to all large spacecraft which generate artificial gravity by rotation. The summary includes a listing of the functions, crew requirements and electrical power demand that led to the studied configuration. The pacing technologies include the benefits of advanced materials, in-orbit assembly requirements, stationkeeping, evaluations of electrical power generation alternates, and life support systems. The descriptions of systems show the potential for synergies and identifies the beneficial interactions that can result from technological advances.

Butterfield, A. J.

A concept for using the external tank from a National Space Transportation System (NSTS) for a lunar habitat

A concept for using the external tank from a National Space Transportation System for a lunar habitat is described. The tank is inserted in low earth orbit where it is outfitted as a 12-person lunar habitat. The tank modifications utilize existing structures and openings for man access without compromising the structural integrity of the tank. The modifications include installation of living quarters, instrumentation, and airlock; and thermal-control, environmental-control and life-support, and propulsion systems. The habitat is designed for unmanned transport to low lunar orbit and autonomously soft landed on the lunar surface. Supply to the habitat is provided by a space transfer vehicle and manned cargo lander. The lunar habitat concept is feasible by the year 2000 with the concurrent development of a space transfer vehicle and manned cargo lander for crew changeover and resupply.

King, C. B.

Concept for a lunar He-3 transporter using an in-orbit modified shuttle external tank

A concept is presented for the transport of gaseous He-3 in temperature equilibrium with the liquid hydrogen and liquid oxygen in a modified lunar shuttle external tank. The concept first describes the internal modifications to accommodate He-3, and then, the external modifications to incorporate a propulsion system and an aerobrake. Estimates of the system masses and an assessment of propulsion requirements show the round trip capability. The concept also includes a description of the lunar orbit servicing and transfer operations.

Butterfield, A. J.

System design analyses of a rotating advanced-technology space station for the year 2025

Studies of an advanced technology space station configured to implement subsystem technologies projected for availability in the time period 2000 to 2025 is documented. These studies have examined the practical synergies in operational performance available through subsystem technology selection and identified the needs for technology development. Further analyses are performed on power system alternates, momentum management and stabilization, electrothermal propulsion, composite materials and structures, launch vehicle alternates, and lunar and planetary missions. Concluding remarks are made regarding the advanced technology space station concept, its intersubsystem synergies, and its system operational subsystem advanced technology development needs.

Queijo, M. J.

Some operational aspects of a rotating advanced-technology space station for the year 2025

The study of an Advanced Technology Space Station which would utilize the capabilities of subsystems projected for the time frame of the years 2000 to 2025 is discussed. The study includes tradeoffs of nuclear versus solar dynamic power systems that produce power outputs of 2.5 megawatts and analyses of the dynamics of the spacecraft of which portions are rotated for artificial gravity. The design considerations for the support of a manned Mars mission from low Earth orbit are addressed. The studies extend to on-board manufacturing, internal gas composition effects, and locomotion and material transfer under artificial gravity forces. The report concludes with an assessment of technology requirements for the Advanced Technology Space Station.

Queijo, M. J.

Analysis of a rotating advanced-technology space station for the year 2025

An analysis is made of several aspects of an advanced-technology rotating space station configuration generated under a previous study. The analysis includes examination of several modifications of the configuration, interface with proposed launch systems, effects of low-gravity environment on human subjects, and the space station assembly sequence. Consideration was given also to some aspects of space station rotational dynamics, surface charging, and the possible application of tethers.

Queijo, M. J.

An advanced technology space station for the year 2025, study and concepts

A survey was made of potential space station missions that might exist in the 2020 to 2030 time period. Also, a brief study of the current state-of-the-art of the major subsystems was undertaken, and trends in technologies that could impact the subsystems were reviewed. The results of the survey and study were then used to arrive at a conceptual design of a space station for the year 2025. Factors addressed in the conceptual design included requirements for artificial gravity, synergies between subsystems, and the use of robotics. Suggestions are made relative to more in-depth studies concerning the conceptual design and alternative configurations.

Queijo, M. J.

Halogen occultation experiment intergrated test plan

The test program plan is presented for the Halogen Occultation Experiment (HALOE) instrument, which is being developed in-house at the Langley Research Center for the Upper Atmosphere Research Satellite (UARS). This comprehensive test program was developed to demonstrate that the HALOE instrument meets its performance requirements and maintains integrity through UARS flight environments. Each component, subsystem, and system level test is described in sufficient detail to allow development of the necessary test setups and test procedures. Additionally, the management system for implementing this test program is given. The HALOE instrument is a gas correlation radiometer that measures vertical distribution of eight upper atmospheric constituents: O3, HC1, HF, NO, CH4, H2O, NO2, and CO2.

Mauldin, L. E., III

Technology evaluation of man-rated acceleration test equipment for vestibular research

The considerations for eliminating acceleration noise cues in horizontal, linear, cyclic-motion sleds intended for both ground and shuttle-flight applications are addressed. the principal concerns are the acceleration transients associated with change in direction-of-motion for the carriage. The study presents a design limit for acceleration cues or transients based upon published measurements for thresholds of human perception to linear cyclic motion. The sources and levels for motion transients are presented based upon measurements obtained from existing sled systems. The approaches to a noise-free system recommends the use of air bearings for the carriage support and moving-coil linear induction motors operating at low frequency as the drive system. Metal belts running on air bearing pulleys provide an alternate approach to the driving system. The appendix presents a discussion of alternate testing techniques intended to provide preliminary type data by means of pendulums, linear motion devices and commercial air bearing tables.

Taback, I.

Circulation control propellers for general aviation, including a BASIC computer program

The feasibility of replacing variable pitch propeller mechanisms with circulation control (Coanada effect) propellers on general aviation airplanes was examined. The study used a specially developed computer program written in BASIC which could compare the aerodynamic performance of circulation control propellers with conventional propellers. The comparison of aerodynamic performance for circulation control, fixed pitch and variable pitch propellers is based upon the requirements for a 1600 kg (3600 lb) single engine general aviation aircraft. A circulation control propeller using a supercritical airfoil was shown feasible over a representative range of design conditions. At a design condition for high speed cruise, all three types of propellers showed approximately the same performance. At low speed, the performance of the circulation control propeller exceeded the performance for a fixed pitch propeller, but did not match the performance available from a variable pitch propeller. It appears feasible to consider circulation control propellers for single engine aircraft or multiengine aircraft which have their propellers on a common axis (tractor pusher). The economics of the replacement requires a study for each specific airplane application.

Taback, I.

Surveys for sensitivity to fibers and potential impacts from fiber induced failures

The surveys for sensitivities to fibers and potential impacts from fiber induced failures begins with a review of the survey work completed to date and then describes an impact study involving four industrial installations located in Virginia. The observations and results from both the surveys and the study provide guidelines for future efforts. The survey work was done with three broad objectives: (1) identify the pieces of potentially vulnerable equipment as candidates for test; (2) support the transfer function work by gaining an understanding of how fibers could get into a building; and (3) support the economic analysis by understanding what would happen if fibers precipitated a failure in an item of equipment.

Butterfield, A. J.