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Hopson, George D.

Publications and source records attributed to Hopson, George D..

Maintainable design for Space Station Freedom

Space Station Freedom poses a unique challenge from the standpoint-of-logistical support and maintainability. There is limited on-orbit stowage volume available for supply of replacement parts for critical systems, and crew time required for maintenance and repair of on-board systems is an extremely valuable commodity. These considerations, plus the high cost of ground-to-orbit resupply, give special importance to the consideration of maintainability in system design. Use of common parts and system redundancy have important influences on logistics and maintenance requirements, and the requirements for specialized crew training and tools are directly related to system design for maintainability. This paper describes the approach for maintainable design of Space Station Freedom systems.

Hopson, George D.

Pressurized modules for Space Station Freedom

Crew workstations, storage, and facilities in the SSF Habitation module along with station housekeeping and supporting subsystems (power, thermal, and life support) are considered. The U.S. Laboratory and Habitation modules are based on a common structural design. The pressurized logistics modules (PLMs) have maximum commonality with the other pressurized modules including common ring frames and waffle grid skin; multilayer insulation and debris shield; and one common endcone.

Hopson, George D.

Verification of Space Station Freedom elements and systems

NASA's Space Station Freedom (SSF) will be assembled in orbit over a period of more than four years, during which the completed sections of the SSF will proceed with research and experimentation. The feasibility of this process is being addressed by the SSF Verification Program (SSFVP), which encompasses development, qualification, acceptance, and prelaunch phases. The SSFVP emphasizes the ground-based verification of the physical and functional compatibility of interfaces for the different elements and launch packages prior to their mating in orbit.

Hopson, George D.

Space Station Freedom pressurized element designs

An overview is given of the pressurized modules of Space Station Freedom. The common design of the modules is described, and the unique features of the U.S. Laboratory/Habitation Module are summarized. The logistics elements and resource nodes for the modules are addressed, and the processes used to manufacture them are discussed.

Grant, Richard L.

Space Station Freedom pressurized element interior design process

The process used to develop the on-orbit working and living environment of the Space Station Freedom has some very unique constraints and conditions to satisfy. The goal is to provide maximum efficiency and utilization of the available space, in on-orbit, zero G conditions that establishes a comfortable, productive, and safe working environment for the crew. The Space Station Freedom on-orbit living and working space can be divided into support for three major functions: (1) operations, maintenance, and management of the station; (2) conduct of experiments, both directly in the laboratories and remotely for experiments outside the pressurized environment; and (3) crew related functions for food preparation, housekeeping, storage, personal hygiene, health maintenance, zero G environment conditioning, and individual privacy, and rest. The process used to implement these functions, the major requirements driving the design, unique considerations and constraints that influence the design, and summaries of the analysis performed to establish the current configurations are described. Sketches and pictures showing the layout and internal arrangement of the Nodes, U.S. Laboratory and Habitation modules identify the current design relationships of the common and unique station housekeeping subsystems. The crew facilities, work stations, food preparation and eating areas (galley and wardroom), and exercise/health maintenance configurations, waste management and personal hygiene area configuration are shown. U.S. Laboratory experiment facilities and maintenance work areas planned to support the wide variety and mixtures of life science and materials processing payloads are described.

Hopson, George D.

Space Station Freedom pressurized element interior design process

The process used to develop the on-orbit working and living environment of the Space Station Freedom has some very unique constraints and conditions to satisfy. The goal is to provide maximum efficiency and utilization of the available space, in on-orbit, zero G conditions that establishes a comfortable, productive, and safe working environment for the crew. The Space Station Freedom on-orbit living and working space can be divided into support for three major functions: (1) operations, maintenance, and management of the station; (2) conduct of experiments, both directly in the laboratories and remotely for experiments outside the pressurized environment; and (3) crew related functions for food preparation, housekeeping, storage, personal hygiene, health maintenance, zero G environment conditioning, and individual privacy, and rest. The process used to implement these functions, the major requirements driving the design, unique considerations and constraints that influence the design, and summaries of the analysis performed to establish the current configurations are described. Sketches and pictures showing the layout and internal arrangement of the Nodes, U.S. Laboratory and Habitation modules identify the current design relationships of the common and unique station housekeeping subsystems. The crew facilities, work stations, food preparation and eating areas (galley and wardroom), and exercise/health maintenance configurations, waste management and personal hygiene area configuration are shown. U.S. Laboratory experiment facilities and maintenance work areas planned to support the wide variety and mixtures of life science and materials processing payloads are described.

Hopson, George D.

The principle of commonality and its application to the Space Station Freedom Program

The principle of commonality has achieved wide application in the communication, automotive, and aircraft industries. By the use of commonality, component development costs are minimized, logistics are simplified, and the investment costs of spares inventory are reduced. With space systems, which must be maintained and repaired in orbit, the advantages of commonality are compounded. Transportation of spares is expensive, on-board storage volume for spares is limited, and crew training and special tools needed for maintenance and repair are significant considerations. This paper addresses the techniques being formulated to realize the benefits of commonality in the design of the systems and elements of the Space Station Freedom Program, and include the criteria for determining the extent of commonality to be implemented.

Hopson, George D.

Rocket Engine Clustering and Vehicle Integration as Influenced by Base Thermal Environments

Clustered rocket engines create severe thermal environments in the base of rocket vehicle stages. Boosters burning hydrocarbon fuels experience severe radiant heating early in flight; as the plumes interact at higher altitudes, convective heating becomes significant. For hydrogen-fueled upper stages radiation is not important, but convective heating is severe during the entire stage operation. Predicted and measured heating rates are discussed. The base region thermal environments of stages with clustered engines present a variety of engine/vehicle interaction problems. Components and structures in the base region, including the rocket engines, cannot survive radiant and convective heating from engine exhausts without such remedies as protective insulation, shielding, air-scooping, and proper disposal of the fuel-rich turbine exhaust gases. Different thermal protection concepts evolve for booster and upper stages due to the differences in ground test and flight environments. Solutions to the engine/vehicle interaction and design integration problems are described.

Hopson, George D.