Abstract: The report describes an invention that is one of the family of AC electric drives permitting a broad range of control of the power of actuating mechanisms with blower-type change of drag torque, e.g., in ship electric power systems, in powerful fan and pump units, etc.

Abstract: A system for operating electrically propelled miniature vehicles along a roadbed having side-by-side current conductive lanes with substantially flush tread surfaces and for remotely controlling the vehicles in a manner to turn out and pass one another at the will of the operator as the vehicles are transferred freely from one lane to another. The vehicles are driven by reversible propulsion motors mounted on the vehicle bodies for operating a pair of rear driving wheels connected by a rear axle. The motor rotates a threaded shaft extending fore and aft of the vehicle body, with a nut threaded on the shaft and operatively associated with front steering wheels to turn the steering wheels in opposite directions depending on the fore or aft movement of the nut in response to opposite rotational movement of the threaded shaft. The reversible propulsion motor is operatively connected to the rear axle through gear trains having oppositely oriented one-way clutches so that the rear wheels are driven by the propulsion motor regardless of the direction of operation of the motor.

Abstract: Theoretical analyses are carried out on a magnetic suspension and a linear synchronous motor, both utilizing superconducting magnets. The derived theory is applied to the studies of the high-speed train models. In the suspension system investigated here, the roadbed is equipped with normal conducting coils. The magnetic lift force is found to be pulsating, and a design criterion for eliminating the pulsation components in the lift force is derived. An improved suspension system is proposed, which consists of a "ladder-type conductor" in the roadbed. This new system is investigated theoretically. An end effect of the suspension system is also studied. In the linear synchronous motor, the methods of minimizing reaction forces are derived. The combined magnetic suspension and propulsion system is analyzed. It is found that the influence of the track loops for the suspension on the linear synchronous motor is not very significant.

Abstract: A realistic mathematical model of the single-sided linear induction motor (SLIM) is presented. Using this model, propulsion and levitation forces are computed for a SLIM with back iron. The validity of the analysis is verified by tests on a laboratory model. Some associated problems are outlined, and the feasibility of SLIM's for high-speed ground transportation (HSGT) is discussed. With regard to HSGT, SLIM is compared with the double-sided linear induction motor.

Abstract: A transportation system wherein a vehicle is magnetically levitated, guided and propelled along a guideway. The vehicle has a number of long thin superconducting coils which, when energized, interact with I-strips in the guideway to effect levitation. Propulsion is accomplished by interaction between further superconducting coils and the field of a linear synchronous motor. In one form, the I-strips are made cryogenic and/or superconducting in and near stations to provide levitation even at very slow speeds and when the vehicle is stationary.

Abstract: This space vehicle is used as a ''''tugboat'''' for propelling other space vehicles. The tug has a pair of propulsion nozzles to which a propulsion fluid is fed by way of an absorption chamber. A large microwave antenna is mounted on the space tug for receiving and concentrating a microwave beam which may come from the earth''s surface. The nozzles and antenna are pivotable relative to each other. Large but short wave guides lead from the feed horn of the antenna through the pivot trunnions for conveying the concentrated microwave beam to the absorption chambers. The beam, which to this point has travelled through a vacuum, is nearly quantitively absorbed by the propulsion fluid which is thereby heated to a plasma. The plasma is directed to the propulsion nozzle by a magnetic field. A single component propulsion fluid is contained in replaceable tanks and energy is imparted to the fluid by way of the microwave beam rather than by chemical reaction. A phased array of antennas permits focusing at high orbital altitudes.

Abstract: : An investigation of air-lubricated foil bearing technology for application in advanced propulsion and power systems was performed. The work conducted under the program comprised: (a) establishment and documentation of the state-of-the-art of foil bearings, (b) development of analytical tools and design guides to permit calculation of the performance of bending-dominated foil bearings, (c) investigation of potential substrate and coating materials, as well as conduct of start-stop and high speed rub tests with two air-lubricated foil bearings at 1000 deg F, (d) preparation of a layout drawing of a dynamic simulator test vehicle based upon an advanced engine (1980 or later time frame) in the 1000 to 3000 pounds thrust class, as well as a description of the test facility requirements, (e) description of the technology segments of air-lubricated foil bearings that need to be advanced to meet the requirements of the advanced engine application, and definition of the parameters for a long range test effort. (Modified author abstract)

Abstract: A magnetic propulsion system includes a roadway having a generally planar upper surface and having a plurality of fieldproducing thrust and levitation elements adjacent the upper surface thereof. The thrust and levitation elements are energized by signal-receiving means associated with the roadway which receive high-frequency signals from signal-producing means on a vehicle. The vehicle has field-producing levitation and thrust elements and the magnetic fields produced by the levitation and thrust elements on the vehicle interact with the magnetic fields produced by the thrust and levitation elements on the roadway to permit controlled propulsion of the vehicle along the roadway.

Abstract: A hydrostatic motor assist vehicle drive system operative at the operator's option to provide intermittent drive to vehicle wheels which are normally idler wheels and which may be dirigible or non-dirigible. Separate propulsion means of any suitable kind is adapted to drive normally operative drive wheels. A vehicle speed responsive control operates independently of an auxiliary drive pump and includes an adjustable flow divider operating between the auxiliary drive pump and assist drive motors to direct fluid drive to the assist drive motors so as to maintain equal rpm of the main and assist drive wheels or equal circumferential distance travelled by such wheels for any increment of time. In one embodiment of a lift truck the auxiliary drive system is operated from the lift cylinder pump with a vehicle speed responsive control operative to control and divide pump discharge between the auxiliary drive system and the lift cylinder.

Abstract: A magnetic propulsion and levitation system for a vehicle which is adapted to travel over an established roadbed. The system includes one or more superconducting magnets carried by the vehicle and a plurality of coils embedded in the roadbed in the path of travel of the vehicle. The coils are sequentially energized at a predetermined position relative to the superconducting magnet for establishing levitation and propulsion forces. The energization of the coils is accomplished by SCR switching elements which are switched on in response to a signal radiated from the vehicle and are switched off by the counter EMF induced in the coils when the superconducting magnet leaves the vicinity of the coil.

Abstract: A simple variable area convergent-divergent exhaust nozzle is provided for an aircraft propulsion system for operation at both subsonic and supersonic aircraft speeds. The variable area exhaust nozzle comprises a system of inner primary flaps which may be simultaneously pivoted and translated about the nozzle axis so as to define a first convergent slightly divergent nozzle suitable for efficient subsonic operation and a second convergent-divergent nozzle suitable for efficient supersonic operation. A system of outer secondary flaps are arranged to pivot in cooperation with the primary flaps so as to define an outer surface which incurs a low external drag through all modes of flight operation.

Abstract: Modern intercity ground transportation requires such high speeds that novel means of suspension and propulsion must be developed. Wheelless trains driven by linear electric motors offer definite advantages with regard to passenger safety and comfort, reliability, efficiency, chemical and noise pollution. Projected densities of traffic may even render economical the transfer of energy from the wayside, by utilizing the mechanism of electromagnetic induction. Various realizations of linear synchronous motors, energized from either the vehicle side or the wayside, are considered, their relative merits, when compared with linear induction motors, are assessed, and the constraints which their peculiar operational and stability characteristics impose on the designer are highlighted. It is concluded that the structural complexity of the linear synchronous motor warrants an effort to make use of the same electromagnets for propulsion, suspension, and lateral guidance. Although sophisticated control systems may be needed, no basic obstacle appears to stand in the way toward the achievement of such a goal.

Abstract: The propulsion system for the descent stage of the lunar module was designed to provide thrust to transfer the fully loaded lunar module with two crewmen from the lunar parking orbit to the lunar surface. A history of the development of this system is presented. Development was accomplished primarily by ground testing of individual components and by testing the integrated system. Unique features of the descent propulsion system were the deep throttling capability and the use of a lightweight cryogenic helium pressurization system.

Abstract: Disclosed herein is a marine propulsion device including a hydropneumatic or gas spring type shock absorber which is connected between a support bracket and a swivel bracket carrying a propulsion unit to damp angular movement of the propulsion unit during tilting, such as during a sudden upward tilting movement of the propulsion unit caused by striking an underwater obstruction while the boat is traveling at a high forward speed. In one embodiment, the gas pressure of the gas spring unit is at a level whereby the tilting force applied by the gas spring unit to the propulsion unit is slightly less than that required to tilt the propulsion unit from an operating position to a raised elevated position, thereby substantially reducing the effort to manually tilt the propulsion unit to a raised position. In another embodiment, the gas pressure of the gas spring unit is at a level whereby the tilting force applied by the gas spring unit to the propulsion unit is greater than that required to tilt the propulsion unit from an operating position to a raised or elevated position so that, upon releasing the locking means releasably locking the propulsion unit in an operating position, the propulsion unit is automatically tilted to a raised or elevated position by the gas spring unit.

Abstract: High‐speed ground vehicles magnetically suspended above a continuous aluminum guideway by superconducting coils can have a clearance of 0.1–0.3 m. To take full advantage of the large clearance, a propulsion system with a comparable clearance is needed. Two such systems based upon physically moving static magnetic fields produced by superconducting coils are proposed. With the use of a prime mover such as a gas turbine or a diesel engine, these systems avoid power collection problems and should result in a lower‐weight propulsion unit. A numerical analysis of each has been made to determine the thrust, the lift force, and the efficiency as a function of various parameters. The mechanical efficiency of the paddle wheel appears to have a maximum of ∼60% at 483 km/h (300 mph), while that of the superconducting screw is (1‐slip) for an infinitely long machine. End effects will degrade the efficiency somewhat for a screw of finite length.

Abstract: A device for use in a spacecraft which combines propulsion fluid storage and flywheel yaw axis stabilization into a single mechanism. It consists of one or more rotating toroidal tanks connected to nozzles through connecting plubming and valves. The rotating tank contains a supply of propulsion fluid in its liquid and vapor phases. The tank is pressurized by heat from any convenient source, such as incident solar energy. As an alternative to rotation of the tank and its contents, an electrically conductive liquid may be rotated with respect to a stationary tank by electromagnetic pumping. By either form of rotation, a flywheel is produced which performs yaw axis stabilization of a spacecraft. Since centrifugal force causes the liquid and vapor phases to be distributed in a predictable manner within the rotating tank, the vapor, which is the desired phase of the fluid for propulsion, can be selectively drawn off and expelled through the nozzles to provide propulsive forces for attitude or minor orbital corrections. Improvement in the specific impulse of the propulsion fluid can be accomplished by electrolytic decomposition of the fluid so as to reduce the average molecular weight of the gas discharged from the nozzles. Further improvement in specific impulse can be attained by causing the products of decomposition to recombine exothermally so as to increase the temperature of the gas discharged from the nozzles.

Abstract: The design and development status of a linear-induction-motor propulsion system intended for use on high-speed ground vehicles is described. In this system, 3-phase, 60-Hz, 8250-V wayside power is converted by a solid-state power conditioning unit to a variable-voltage variable-frequency output suitable for use by linear-induction motors that provide up to 66 600-N (15 000-lb) propulsive thrust to the vehicle at 480 km/h (300 mi/h). The system provides continuously variable thrust during forward- and reverse-thrust modes, and such special features as automatic start-up, regenerative braking, and automatic failure/malfunction detection and shutdown. The system incorporates high-voltage water-cooled components for high specific thrust (more than 5 N/kgf, or 0.5 lbf thrust/lbf weight).

Abstract: A propulsion system for a boat is hydraulically driven and has a propeller close-coupled to an immersible hydraulic motor unit, the motor unit being carried on a support enabling the motor unit to swivel, for steerage, and to tilt so that the thrust developed by the propeller can be used to assist in trimming the boat fore and aft, the support furthermore enabling the motor unit and propeller to be swung into an enclosing casing for their protection when out of use.

Abstract: : A water electrolysis satellite propulsion system capable of providing 100,000 pound-seconds of impulse during a seven year life was fabricated and tested in three modes of operation -- simple blowdown, helium repressurization and repressurization by oxygen in a feedback mode. The tests verified the systems predicted capabilities in all three modes at generation rates of 0 to 2. 3 lbs/day of propellant, with an electrical energy conversion efficiency of up to 82%. 5.0 pound thrust and a 0.1 pound thrust GO2/GH2 engine were tested as separate components with measured specific impulses of 345 and 330 seconds, respectively, at a mixture ratio of 8. The 0.1 pound engine accumulated 14,330 seconds of burn time and 151,263 ignitions, while the 5 pound thrust engine attained 10,031 seconds of burn time and 69,700 ignitions. The demonstrated overall performance of the system and engines shows its applicability to satellite and spacecraft which require high performance, reliable operation, and long life capabilities.

Abstract: A three-wheeled tricycle which may be manually propelled by the operator or quickly converted to electrical power propulsion by the simple manipulation of suitable controls by the operator.

Abstract: The Apollo launch escape propulsion subsystem contained three solid rocket motors. The general design, development, and qualification of the solid-propellant pitch-control, tower-jettison, and launch-escape motors of the Apollo launch escape propulsion subsystem were completed during years 1961 to 1966. The launch escape system components are described in general terms, and the sequence of events through the ground-based test programs and flight-test programs is discussed. The initial ground rules established for this system were that it should use existing technology and designs as much as possible. The practicality of this decision is proved by the minimum number of problems that were encountered during the development and qualification program.

Abstract: One limitation encountered by chemical rocket propulsion in high pressure planetary atmospheres is illustrated by the conflict between the dependence of specific impulse on the ratio of chamber pressure to ambient pressure and the dependence of the motor structural design on the difference between the pressures. This work proposes to resolve the difficulty by employing detonating propellant in which the high pressures necessary for efficient propulsion are developed over a short time and need not be contained statically. Experimental results are presented to substantiate this claim of relatively high performance, together with an analytical development that approximately describes the flow dynamics.

Abstract: This article discusses electrical propulsion, principally in connection with satellite station-keeping, and indicates the optimum conditions for meeting a specific requirement. Different types of propulsion, and the performances which they have currently achieved, are reviewed. Recent developments in colloid thrusters are described in detail, together with the diagnostic equipment for measuring their performance and efficiency.

Abstract: An improved liquid pumping unit for marine propulsion and the like includes as the rotatable shaft of an internal combustion engine a conduit which includes internal impeller vanes for pumping liquid therethrough at high volume and velocity and which also serves as the flywheel of the engine.

Abstract: A rapid transit system which transports people and articles including automobiles, small trucks and the like throughout a network of local, branch or regional transit routes. The transit vehicle is a unitary, self-supporting structure which is transported and guided by spaced sets of wheels mounted and turning on pylons. The transit vehicle is compartmented into cubicles in one rigid structure which could be approximately 21 feet wide by 60 feet high and 1,500 to 2,000 feet long. The pylon construction supports the transit vehicle above the right of way property, typically at a minimum height of approximately 60 feet. Each pylon includes an upper power frame assembly having a large wheel for supporting and four smaller wheels for guiding the transit vehicle. A base frame mounted between the pylon and it foundation is provided when necessary to compensate for changes in grade. Motors driving the wheel are used to propel the transit vehicle over the pylons. These may be external motors driving through the propulsion wheel shaft or the propelling rotor may be integral with the propulsion wheel driving against stator coils framed from the bearing hub structure. Guide wheels on opposite sides of the power frame of the pylon are geared to turn at the same tread velocity as the propulsion wheel and absorb the wind side load of the vehicle. The power frame may include transformers, rectifiers, power controls, circuit breakers and other control and highly failsafe operating equipment responsive to the networks (remote) central control system. The transit vehicle is an elongated truss which would extend from one pylon to another in a cantilevered fashion. Thus the transit vehicle may engage with the next pylon approximately 300 feet away providing the only bridge for the vehicle as it proceeds along the route. The system would include local routes that would eventually become integrated with branch and regional routes within the system. The pylons may be individually mounted on mobile trucks to roll in groups on tracks or rails to be moved sideways to simultaneously move the transit vehicle in this fashion. The pylons may be removed and be replaced as required by the transit vehicle itself so that the transit may continue uninterrupted.

Abstract: An electrical model of a plurality of simultaneous equations, such as equations representing a dynamic propulsion system, is disclosed as including a plurality of transformers generally greater in number than the number of equations to be solved. Each transformer includes a plurality of windings with a separate winding of each transformer provided for each different variable of the simultaneous equations. The windings of the respective transformers representing the same variable of the equations are coupled together to form a group of such windings representing one of the simultaneous equations. Electrical signals having values representing invariant conditions to be solved by the equations are coupled to the appropriate group of windings and output signals are induced in output windings of the transformers which are a function of the input voltage applied. A specific example of a dynamic propulsion system represented by such equations is a thruster control system for controlling a plurality of thrusters propelling or positioning a floating vessel, which as an offshore drilling vessel. In this example, the simultaneous equations to be solved are those representing the available degrees of freedom of the thrusters and internal constraints designed to optimize thruster operations.

Abstract: Description of a three-year exploratory research program for the design, development, and flight evaluation of an Integrated Propulsion Control System (IPCS). The primary objectives of this program are to establish through flight test the potential improvements in steady-state and transient propulsion system performance that can be achieved as a direct result of new modes of control, more direct sensing of engine and inlet parameters, and the use of more sophisticated, high-speed digital computation. A F-111 E aircraft with the left inlet and engine modified to the IPCS configuration will be used to conduct the flight evaluation.

Abstract: An analytical investigation of single-stage vehicles with multiple propulsion phases has been conducted with the phasing optimized to minimize a general cost function. Some results are presented for linearized sizing relationships which indicate that single-stage-to-orbit, dual-fuel rocket vehicles can have lower inert weight than similar single-fuel rocket vehicles and that the advantage of dual-fuel vehicles can be increased if a dual-fuel engine is developed. The results also indicate that the optimum split can vary considerably with the choice of cost function to be minimized.

Abstract: This paper is a digest of the electrical system section of a report [8] on the feasibility of using a hybrid heat engine/electrical propulsion system as a means of reducing exhaust emissions from street-operated vehicles. The electrical system is composed of an electric traction motor, a generator, control system, and batteries. Batteries are not covered in this paper, but the remainder of the items will be treated here. First, the electrical system parameters or characteristics that have the greatest impact on the total system are considered; next, details of the advantages and disadvantages of various approaches are summarized; and, finally, development efforts are recommended.