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The work reported in this paper has been conducted by a team from GE-Aircraft Engines, GE-CR&D, and Sundstrand under a contract sponsored by the USAF, Wright Laboratories, WPAFB, Contract No. F33615-90-C-2052. The objective of this contract is to prove the feasibility of an Integral Starter/Generator (IS/G) through the preliminary design stage and demonstrate the starter/ generator technology in the externally mounted version utilizing switched reluctance machine technology. This paper will report on the progress for the EIS/G-system through the initial testing stage. Comparison of the finished hardware with the design results presented earlier will lead of the paper. This is followed by the discussion of the early testing results for the system testing. Recommendation on additional testing will be presented at the end of the paper.

This paper describes the design, implementation, and performance test results of an engineering model of the Position Multiplexer (MUX)-Analog Input Processor (AIP) System for the transmission and continuous measurements of Reflector Control Drive position in SP-100. The specially tailored MUX-AIP combination multiplexes the sensor signals and provides an increase in immunity from low frequency interference by translating the signals up to a higher frequency band. The modulated multiplexed signals are transmitted over a single twisted shielded cable pair from the reflector drives located near reactor to the AIP located at the power conditioning/system controller end of the space craft boom. There the signals are demultiplexed and processed by the AIP, eliminating the need for individual cables for each of the twelve position sensors across the boom.

Recent Generic Flight System (GFS) updates have necessitated revisions in the initial startup and restart control strategies. The design changes that have had the most impact on the control strategies are the addition of the Auxiliary Cooling and Thaw (ACT) system for preheating the lithium filled components, changes in the reactivity worths of the reflectors and safety-rods such that initial cold criticality is achieved with only a small amount of reflector movement following the withdrawal of the safety-rods, and the removal of the scram function from the reflectors. Revised control and operating strategies have been developed and tested using the SP-100 dynamic simulation model, ARIES-GFS. The change in the total reactivity worths of the reflectors and safety-rods has eliminated the need for the use of fast and slow reflector drive speeds during the initial on-orbit approach to criticality.

As part of the SP-100 Space Reactor Power System Program being undertaken for the U. S. Department of Energy, GE is developing a thermoelectric (T/E) power converter which utilizes reactor delivered heat and transforms it into usable electric power by purely static means. This converter is based to GE's product line of successful thermoelectric space power systems. The SP-100 power converter embodies the next generation improvement over the type of T/E converter successfully flown on the six U. S. space missions. That is, conduction coupling of T/E cell to both the heat source and the heat rejection elements. The current technology utilizes radiation coupling in these areas. The conduction coupling technique offers significant improvements in system specific power since it avoids the losses associated with parasitic ΔT's across the radiation gap between the heat source and the hot junction of the thermoelectric (T/E) cell.

The term “SP-100” is synonymous with a set of technologies that can be utilized to provide long lifetime, reliable, safe space power over the range of kilowatts to megawatts [1] using a nuclear reactor as the heat source. This paper describes recent development progress in a number of technology areas such as fuel, materials, reactivity control mechanisms and sensors. Without exception, excellent technical progress is being accomplished in all areas under development to optimize spacecraft performance characteristics.

Early flight mission objectives can be met with a Space Reactor Power System (SRPS) using thermoelectric conversion in conjunction with fast spectrum, lithium-cooled reactors. This paper describes two system design options using thermoelectric technology to accommodate an early launch. In the first of these options, radiatively coupled Radioisotope Thermoelectric Generator (RTG) unicouples are adapted for use with a SP-100-type reactor heat source (Deane 1992). Unicouples have been widely used as the conversion technology in RTGs and have demonstrated the long-life characteristics necessary for a highly reliable SRPS (Hemler 1992). The thermoelectric leg height is optimized in conjunction with the heat rejection temperature to provide a mass optimum 6-kWe system configured for launch on a Delta II launch vehicle. The flight-demonstrated status of this conversion technology provides a high confidence that such a system can be designed, assembled, tested, and launched by 1996.

The approach that was utilized to start up and requalify manufacture of the thermoelectric unicouple devices for the Cassini RTG (Radioisotope Thermoelectric Generator) program are described in this paper. Key elements involved in this effort were: engineering review of specifications; training of operators; manufacturing product verification runs; and management review of results. Appropriately, issues involved in activating a fabrication process that has been idle for nearly a decade, such as upgrading equipment, adhering to updated environmental, health, and safety requirements, or approving new vendors, are also addressed. The cumulative results of the startup activities have verified that a production line for this type of device can be reopened successfully.

To facilitate the development of the Space Reactor Power System (SRPS) controller, a rapid prototyping and multi-phased development methodology is being utilized. The rapid prototyping environment used in the development models both the controller and the system being controlled. Since the validation of the SRPS control strategies is a long lead activity to ensure the required safety and control features, the SRPS controller development is carried out in phases, starting with normal modes of operation and followed by transient and off-normal modes. In every phase, the rapid prototyping of the control strategies is used (1) to establish well-defined controller requirements, (2) to perform fast identification of changes and refinement of the strategies, and (3) to conduct in-phase correction and optimization of the strategy and component development.

Researchers now have the means to evolve complex manned and unmanned space missions using all of their complex support systems in a fully adaptive visual environment. The expected interactive nature of space missions requires powerful, flexible and comprehensive simulation hardware and software to develop and verify concepts, systems, and procedures. Correlation of visual, sensor, and radar imagery is essential due to new sensor blending and fusion techniques that characterize complex systems and missions. Only through total visual, non-visual and mission environment simulation, combined with analytical tools, can reliable systems and missions be developed. The same can be said of the simulation-based training programs that must be developed for ground and flight mission crews. If maximum situational awareness cannot be trained through simulation, it may be too risky, too expensive or even too late to acquire during a mission.

This paper discusses the technology, components and systems incorporated in the design of the LM1600 I/CR marine gas turbine propulsion system as well as describing some of the novel and imaginative ways that the highly acclaimed F404 fighter aircraft engine has been modified and adapted to provide the nucleus for this sophisticated marine propulsion system. Specifically, the modifications to the compressors, the high and low pressure turbines and the power turbine design characteristics are described. The proven materials technology from the highly successful LM2500 marine gas turbine has been applied to this engine as well.

Today's instrument panel specifications for passenger cars are also applied to most light trucks and vans because internal company standards are dictating that light trucks and vans should approach the occupant safety of existing cars. In this presentation, we will examine the traditional specifications for pre-1988 model year, which center on a few key materials and part performance properties, and the increasing number of specifications which are being called for in 1988 model year and beyond, which require altogether new materials and processing systems. (Throughout this discussion, it should be noted that in referencing “automobiles” we are including light trucks and vans.)

A new silicone rubber formed-in-place gasketing concept has been developed which has greatly reduced the incidence of warranty oil leaks in engine and drive train components. This concept utilizes a combination of joint configuration and unique cured properties of the silicone formed-in-place gasketing material to achieve leak-free performance over the life of the component.

An organic Rankine Bottoming cycle added to Diesel engines used for long-haul trucks has the potential of improving their peak fuel economy by up to 15% over a typical duty cycle. General Electric has developed a multi-vane rotary expander which has a measured isentropic brake efficiency of 80+% over a wide range of speed and power levels with organic working fluids. High cycle efficiency for design and off-design conditions is achieved with the multi-vane expander. The potential advantages of the multi-vane expander for the Diesel engine bottoming cycle include the elimination of a high speed gear box and the potential for over 80% isentropic engine efficiency. The multi-vane expander is a ruggedly built component running at Diesel engine speed. This paper describes the design and evaluation of a nominal 40 HP multi-vane expander for this application.

The principal design features of the NASA QCSEE UnderThe-Wing and Over-The-Wing powered lift propulsion systems are given. In the UTW engine, these include noise reduction features, a variable pitch low pressure ratio fan, a fan drive reduction gear, an advanced core and low pressure turbine with a low pollution combustor, a digital control, and advanced composite construction for the inlet, fan frame, fan exhaust duct, and variable area fan exhaust nozzle. The OTW engine is similar but has higher fan pressure and a fixed pitch fan. Both engines are scheduled to be fabricated and tested starting in 1976.

A new ultrathin-backed semipermeable membrane has been developed which shows considerable promise as a gas separator for engine bleed air to provide nitrogen-rich air for aircraft fuel tank inerting. The membrane is a silicone, polycarbonate copolymer of 1500 Å effective thickness, deposited on a reinforced porous backing. The selective removal of oxygen provides oxygen concentrations of less than 9% in the inerting gas. Small-scale testing demonstrated that the backed membranes are suitable in the aircraft environment. A system using such membranes avoids the logistic and service requirements of tanked liquid nitrogen.

Previous studies had demonstrated the economic and technical feasibility of producing high-quality forgings for aircraft turbine engine parts from hot-isostatically pressed (HIP) Rene 95 powder billets. The present program was aimed at developing a production practice for making HIP + forged turbine discs. The major goal was improved product fabricability and reliability with minimum cost. The program was conducted using argon atomized Rene 95 powder. Experimental studies were conducted to evaluate the effect of powder characteristics, HIP parameters, preform design, and forging conditions on forgeability, microstructure, and mechanical properties. The results of these studies were incorporated into a pilot production run in which 10 disc forgings were made and evaluated. The selected process involved the consolidation of -60 mesh powder to full density by hot-isostatic pressing at a temperature above the γ' solvus temperature.

A method for measurement of rolling resistance of vehicles using only a single accelerometer measurement has been developed and a simple instrument has been constructed. Results of typical measurements on large, electrically propelled off-highway trucks are discussed.

The advantages of infinitely variable ratio steering and propulsion for track laying vehicles are well known. Studies and demonstrator programs in the past decade have indicated that the hydromechanical transmission has the most promise of providing infinitely variable ratio for military vehicles. In 1966 the Army launched a program to develop the hydromechanical transmission to “production ready” status. This paper describes that program, the transmission selected, and some of the problems encountered in the transition from the demonstrator stage to one of readiness for military application.

The General Electric Company has recently been in the process of developing two new turbofan aircraft engines-the TF34 and the F101. The TF34 has been developed for the U.S. Navy's S-3A antisubmarine warfare aircraft and has been selected by Fairchild-Hiller for the U.S. Air Force A-10A; the F101 is being developed for the U.S. Air Force B-1 strategic bomber. Each of the new aircraft programs has the common requirement for subsonic endurance. The S-3A and A-10A requirements include subsonic operation only while the B-1 includes supersonic capability as well as subsonic. This basic mission-mix difference combined with major differences in engine/air vehicle installation features and different levels of technology applied due to the relative chronology in the respective development programs leads to contrasts in the design features of the major components of the engines.

Aircraft starting and generating systems heretofore have been largely the result of joining together available components. Recent studies have demonstrated that substantial benefits in weight, cost, size, and performance may be realized through a total system approach. This paper identifies the types of information required, and the methods of system analysis employed, to design an optimized system.