Abstract: A bearing protection arrangement of a journal bearing arranged between a housing and a rotary component of a wind turbine. The bearing protection arrangement includes a wind speed monitor arranged to monitor wind speed in the vicinity of the wind turbine and to generate a wake-up signal when the wind speed exceeds a pre-defined minimum; a mode switch module of a backup battery arranged to provide restart power to an auxiliary of the wind turbine, which mode switch module is adapted to switch the backup battery from a normal-power mode into a low-power mode to conserve sufficient restart power after low wind-speed conditions, and to switch the backup battery from the low-power mode into a normal-power mode in response to the wake-up signal. A wind turbine and a method of protecting a journal bearing of a wind turbine during standstill.

Abstract: A method of pitching rotor blades by interrupting torque applied to the hub.

Abstract: A variable pitch propeller assembly operatively coupled with an engine and methods for controlling the pitch of a plurality of propeller blades thereof is provided. In one example aspect, the variable pitch propeller assembly includes features for combining overspeed, feathering, and reverse functionality in a single secondary control valve. The secondary control valve is operable to selectively allow a controlled amount of hydraulic fluid to flow to or from a pitch actuation assembly such that the pitch of the propeller blades can be adjusted to operate the variable pitch propeller assembly in one of a constant speed mode, a feather mode, and a reverse mode.

Abstract: Provided is a wind turbine rotor blade pitch bearing for mounting a rotor blade to a hub, including a carrier with an annular arrangement of bearing pad seats; a plurality of bearing pads, wherein a bearing pad is arranged in each bearing pad seat of the carrier; and a gripping assembly for gripping the carrier, which gripping assembly including a sliding part arranged to lie against an annular arrangement of bearing pads and further includes an access window dimensioned to expose a bearing pad when opened. A wind turbine with a number of such pitch bearings; and a method of performing a service routine on a wind turbine rotor blade pitch bearing is further provided.

Abstract: One aspect is a flight control system for a rotary wing aircraft that includes flight control computer configured to interface with a main rotor system, a translational thrust system, and an engine control system. The flight control computer includes processing circuitry configured to execute control logic. The control logic includes a primary flight control configured to produce flight control commands for the main rotor system and the translational thrust system. A main engine anticipation logic is configured to produce a rotor power demand associated with the main rotor system. A propulsor loads engine anticipation logic is configured to produce an auxiliary propulsor power demand associated with the translational thrust system. The flight control computer providing the engine control system with a total power demand anticipation signal based on a combination of the rotor power demand and the auxiliary propulsor power demand.

Abstract: A device for controlling a propeller, having variable-pitch blades, of a turboprop engine, has a first hydromechanical device for controlling the pitch of the blades of the propeller and a second hydromechanical device for controlling the speed of rotation of the propeller. The device includes a single electromechanical actuator with a movable actuator member mechanically connected both to the first hydromechanical device for controlling the pitch, in order to manage the pitch setpoint, and to the second hydromechanical device for controlling the speed, in order to manage the speed setpoint.

Abstract: A method of optimizing the power recovered by a wind turbine by reducing the mechanical impact on the structure is disclosed. A first angle of inclination of the blades allowing the recovered power to be optimized is determined. The aerodynamic force produced on the nacelle when the blades are directed with a first angle is determined. A second angle of inclination of the blades allowing obtaining an aerodynamic force setpoint value is then determined by inverting the aerodynamic force model and using a wind velocity measurement, a rotor velocity measurement and the aerodynamic force setpoint value. Finally, the blades are directed to the second angle.

Abstract: Embodiments of a single lever turboprop control method and system are provided, which utilize torque-based and/or power-based scheduling to achieve a desired (e.g., substantially proportional) relationship between control lever position and the power output of a turboprop engine. In one embodiment, the method includes the step or process of monitoring, at an Engine Control Unit (ECU), for receipt of a Power Lever Angle (PLA) signal from a single lever control device. When a PLA control signal received at the ECU, a target torque or power output is established as a function of at least the PLA control signal. A first engine setpoint, such as a blade angle setpoint or an engine rotational speed setpoint, is determined utilizing the target torque output. An operational parameter of the turboprop engine is then adjusted in accordance with the first engine setpoint.

Abstract: A method and control system for an aircraft using a gas turbine engine is provided. The control system includes a controller that includes a load and engine control modules and communicates control signals to a plant that includes a gas generator and a rotor load, an engine estimation module that receives engine state measurements and effector feedback/command signals from the controller and communicates a power turbine torque estimate, and a load estimation module that receives signals including the power turbine torque estimate, a first power turbine speed value, a first power turbine torque value, a second power turbine speed value, a second power turbine torque value, and a rotor speed value. The load estimation module generates one or more of a power turbine speed estimate, a power turbine torque estimate, and a rotor load estimate based on the received signals.

Abstract: A turboprop control system 10 for use with a turboprop 2 having a turbine engine 12 operably coupled to and rotationally driving a propeller 14 having variable pitch blades 16 to control the engine speed, propeller speed, and propeller pitch. The pilot provides, by a single power control lever 30, the control input used to control the engine and propeller.

Abstract: A method and control system for an aircraft engine comprising a gas turbine driving a fan propeller with a mechanical gear-train and a dedicated pitch change mechanism for the fan propeller includes a fuel flow signal input; a pitch change mechanism signal input; a controlled plant for relating a pitch change mechanism pitch angle (BetaP) and a fuel flow (Wf) to at least two controlled outputs and a set of constraints. A decoupling control decoupling the controlled plant and/or the constraints into two separate single-input single-output (SISO) control loops for the first and second controlled outputs and a decoupling control decoupling the constraints from the decoupled controlled outputs and the constraints from one another provide gas turbine and fan propeller coordinate control while coordinately controlling constraints and outputs. A feedforward control can compensate the load change effect on engine speed and fan propeller rotor speed control.

Abstract: A system and method for blade angle position feedback. The system comprises an annular member operatively connected to rotate with a propeller, a sensor fixedly mounted adjacent the annular member and configured for detecting a passage of each singularity as the annular member is rotated and axially displaced and for generating a sensor signal accordingly, the annular member and sensor configured for relative axial displacement between a first relative axial position and a second relative axial position respectively corresponding to the first and the second mode of operation, and a detection unit connected to the sensor for receiving the sensor signal therefrom, determining on the basis of the sensor signal a time interval elapsed between the passage of successive singularities, and computing from the time interval blade angle position.

Abstract: A method of controlling an aircraft gas turbine engine cooling system. The cooling system includes a heat exchanger having a first fluid path through which fan air flows, and a second fluid path through which relatively hot compressor air flows. The cooling system includes a valve configurable between an open position corresponding to a first operating mode, where fan air flows through the first path cooling the compressor air in the second path to a lower temperature, and a closed position corresponding to a second operating mode, where fan air may flow through the first path at a reduced rate, thus the compressor air in the second path could be cooled to a lesser extent. The valve is operated in first mode when the aircraft is in a descent mode, or when turbine entry temperature is above a predetermined amount. Otherwise, the valve is operated in second mode.

Abstract: A method for evaluating a collective alignment of rotor blades for an aircraft while the aircraft is on the ground is disclosed. The method includes determining an air density altitude, and determining a torque value for each engine of the aircraft, while the aircraft rotor blades are operated at a normal speed and the rotor blades are set to a full down position for ground operations via a collective controller. The method further includes evaluating the collective condition by comparing the torque value to a predetermined flat pitch torque alignment limit for the air density altitude, and providing an indication of the collective condition.

Abstract: A wind turbine having a set of curved blades mounted on a central rotatable hub. Each of the blades has a defined pitch angle, to a rotational axis of the hub, along the blade from the hub to the tip. A curve is provided on the wind contact surface along each of the blades over the blade surface from the leading edge of the blade to the trailing edge of the blade by an amount between about 6 and about 24 degrees. The defined pitch angle from any point along the leading edge of the blade being defined by the arc-sine of a ratio of blade velocity to apparent wind velocity, with a variance of ±30 percent of the complementary angle to the arc-sine; and apparatus for varying the velocity of the blade to control power output so that it is within fifteen percent of maximum obtainable power of the blade most distant from the hub.

Abstract: A present invention relates to a novel hybrid intelligent control system and method for power generating apparatuses, in which the control system comprises: a fuzzy sliding mode speed controller, embedded with a fuzzy inference mechanism so as to be used for controlling the speed of a power generating apparatus; and a radial basis function network (RBFN) pitch controller, being embedded with an on-line training RBFN so as to be used for controlling the pitch angle of a turbine coupled to the power generating apparatus. In a variable-speed energy conversion system using the aforesaid control system, the turbine can be driven to operate at its maximum efficiency by adjusting its blade pitch angle in response to the variation of the input flowing into the turbine, while allowing the shaft speed of the power generating apparatus to be controlled by a fuzzy interference mechanism so as to achieve its maximum power output.

Abstract: A method of deploying offshore wind turbine assemblies includes mounting a wind turbine assembly horizontally on a vessel and transporting the wind turbine assembly to an offshore site. The wind turbine assembly is raised to a vertical condition at the site and attached to anchor weights. Blades are attached to the turbine head after the wind turbine assembly is in the vertical condition. In one embodiment, the wind turbine assembly can include a tower including tapered lower and upper sections joined together at their respective wide ends, a turbine head connected to the upper section, and a platform connected to the lower section. The platform includes a buoy tank partially filled with ballast to provide mass and buoyancy. A wave piercing cowling is rotatively attached to the lower section. The turbine head can include an adjustable journal bearing, scabbard blade mounts, and a gearless induction generator with flux adjusting capabilities.

Abstract: A device for improving performance of an aircraft with a propeller includes a constant torque blade setting device that slaves, automatically and independently, blade setting angles, respectively associated with blades of the propeller, to a constant reference control moment predetermined, for a desired propeller thrust value. The blade setting angles are intended to be applied on each blade such that torsion aerodynamic moments applied on blades stay roughly equal to the reference control moment regardless of the angular position of blades in the propeller plane. A corresponding method for improving performance of an aircraft includes the use of the constant torque blade setting device to slave blade setting angles to a constant reference control moment.

Abstract: Blades of a wind turbine attached to a rotor hub for rotation in a rotor plane may be adjusted by a control system for individually pitching the blades relative to the hub. The rotor planes divided into a plurality of predefined section, wherein each section has an associated pitch reference value. A light detection and ranging device may be used to determine expected properties of wind in each respective section of the rotor plane so that the pitch reference value may be adjusted accordingly.

Abstract: A variable pitch propulsor system with a propeller pitchlock system having a pitchlock solenoid valve located in communication with a pitchlock pressure circuit to selectively actuate pitchlocking in response to a controller. The pitchlock solenoid valve includes an electro-mechanical device which is normally closed but may be commanded to electrically open and dump the pitchlock pressure which causes actuation of the pitchlock system. The pitchlock solenoid provides a mechanism which will selectively pitchlock the propulsor system; permits a built in test routine to determine the condition of the pitchlock system through a commanded propeller pitchlock sequence; requires no mechanical link between the rotating and non-rotating propeller components to initiate pitchlock; is independent of engine and gearbox configurations; and can initiate pitchlock remotely with a signal from a remote location.

Abstract: The invention relates to aeronautical engineering, in particular to methods of flight due to creating of forces on air propellers, namely using thrust vectoring of direction and amount of force created by air propellers of opposite rotation with the axis, mainly in the direction of flight, in the expanded range of speeds, from 50 m/s to high near-sonic speed of flight. The invention may be applied for horizontal flight and maneuvering in flight on vertical take-off aircrafts using rotation of main rotors from the vertical stand of rotor axes during the take-off to almost horizontal position of rotor axes in horizontal flight, thus both the rotation of rotors and the change of position of an aircraft together with its rotors may be applied, and it may be also used in the horizontal take-off aircrafts with almost horizontal position of axes during the horizontal flight, including the planes with airscrew propellers.

Abstract: The present invention relates to a method of controlling the aerodynamic load of a wind turbine blade by controlling the tip speed ratio (TSR) and/or blade pitch setting of the wind turbine blade so as to optimize power production. A wind turbine blade undergoes an aero-elastic response including deflection and twist that is a function of the blade loading. The blade loading is dependent on the wind speed, TSR, and pitch setting. The aero-elastic response requires a different TSR and/or pitch to be selected throughout the power curve in order to maintain the optimum power production and to improve energy capture.

Abstract: A plain bearing assembly for mounting a blade to a hub of a wind turbine includes an outer member mountable to one of the blade or hub, and an inner member mountable to the other of the blade or hub and movable relative to the outer member. The plain bearing further includes fluid cavities associated with one of the outer or inner member and arranged to confront the other of the outer or inner member. The fluid cavities are coupled to a pressure source for establishing a pressurized fluid film between the inner and outer members. A method includes monitoring at least one parameter of the fluid film, comparing the at least one parameter to a threshold criteria, and altering a dynamic state of the wind turbine and/or altering the state of the blade bearing assembly if the threshold criteria is exceeded.

Abstract: The invention relates to a method for the operation of a wind energy plant (10), wherein the wind energy plant (10) has a rotor (11) with a rotor axis and at least one rotor blade (15, 15?) arranged on the rotor (11), wherein the rotor blade (15, 15?) is adjustable or adjusted around a rotor blade axis with a predetermined rotor blade pitch angle. Further, at least one rotor blade (15, 15?) is rotated into an idle position, the rotation of the rotor blade (15, 15?) is braked after a first predetermined rotational position of the rotor blade (15, 15?) is reached and the stand-still position of the rotor blade (15, 15?) reached as a result of the braking procedure is captured. Furthermore, the invention relates to a wind energy plant (10) with a rotor (11) and at least one angle-adjustable rotor blade (15, 15?) arranged on the rotor (11).

Abstract: Controller for a blade adjustment angle for at least one rotor blade of a wind power plant, in which a first controller branch is switched for the determination of the blade adjustment angle depending on the operating states of the wind power plant, wherein at least one differentiating member is provided in the switched first controller branch.

Abstract: A method for monitoring wear of a blade pitch brake within a rotor blade pitch control system of a wind turbine is described. The rotor blade pitch control system includes a blade pitch actuator. The method includes engaging the blade pitch brake and measuring a blade pitch displacement while the blade pitch brake is engaged. The method further includes determining a brake wear level based on the measured blade pitch displacement while the blade pitch brake is engaged, and generating a brake wear level output signal corresponding to the brake wear level.

Abstract: A dual redundant permanent magnet type dynamoelectric machine includes a dual flux throttle system to selectively disable one of a first motor and a second motor.

Abstract: A method for controlling a pitch control system of a wind turbine includes providing a charged backup battery configured to supply no energy to a DC link when full AC input power is available, wherein the DC link includes a DC link capacitor. The method further includes using energy stored in the DC link capacitor to operate a pitch control system during a loss or dip of AC input power, and maintaining charge on the DC link capacitor using the charged backup battery as voltage across the DC link capacitor drops during the operation of the pitch control system.

Abstract: A wind turbine generator, an active damping method thereof, and a windmill tower in which vibrations of the wind turbine generator itself or the windmill tower can be reduced at low cost are provided. The acceleration due to vibrations of a nacelle (13) is detected with an accelerometer (17) attached to the nacelle (13). In an active damping unit (20), a pitch angle of windmill blades (12) for generating a thrust on the windmill blades (12) so as to cancel out the vibrations of the nacelle (13) is calculated on the basis of the acceleration, and the pitch angle is output as a blade-pitch-angle command ??* for damping. On the other hand, in a pitch-angle control unit (30), a pitch angle of the windmill blades (12) for controlling the output to be a predetermined value is calculated, and the pitch angle is output as a blade-pitch-angle command ?* for output control. The blade-pitch-angle command ??* for damping is combined with the blade-pitch-angle command ?* for output control using a subtracter (40).

Abstract: This document discusses, among other things, a wind turbine blade pitch system for moving the blades to control their pitch in the event of a power failure. The system includes at least one backup that has a non-electrical component that can pitch the blades in the event that the power failure adversely affects the electrical blade pitch actuator system. Embodiments include pitch systems that have a plurality of pitch driving systems including, but not limited to electrical systems, hybrid electrical/mechanical systems and non-electrical systems. The non-electrical systems include mechanical, pneumatic or hydraulic systems.

Abstract: Apparatus for controlling the power output efficiency of a power generation system based on an operator input. A processor is coupled to the input means and (i) receives the generated operator command, (ii) receives a plurality of detected ambient air conditions, (iii) receives a plurality of detected engine performance parameters, (iv) determines first and second engine control commands based on the received pilot thrust command, the detected ambient environmental conditions, and the engine performance parameters, and (v) outputs control commands to optimize the efficiency of the power generation system.

Abstract: A system is disclosed for determining the total torque required at the main and tail rotors of a helicopter for use in feed-forward rotor torque anticipation which includes a polynomial neural network adapted and configured to predict the aerodynamic torque at the main and tail rotors with the helicopter in motion based upon a plurality of pilot inputs and airframe inputs, a main rotor load map for determining the torque at the main rotor in hover out of ground effects based upon main rotor speed and collective stick position, a tail rotor load map for determining the torque at the tail rotor with the helicopter stationary based upon main rotor speed and pedal position, and a processor for calculating the required total torque at the main and tail rotors by summing the outputs of the polynomial neural network, and the main and tail rotor load maps.

Abstract: A pop-off valve that, in one embodiment, provides overboost protection for an aircraft engine, is described. The pop-off valve includes a housing adapted for connection to a portion of a drive device containing a pressure medium. It also includes a pressure body movably disposed in the housing such that, in operation, a first side of the pressure body is exposed to the pressure medium while a second side is exposed to a reference force. In addition, the pop-off valve incorporates a control device adapted to receive at least one signal concerning at least one operating parameter of the drive device and, in response to the operating parameter signal, to control the reference force. As a result of movement of the pressure body within the housing, at least one first opening in the housing is exposed, permitting venting of the pressure medium.

Abstract: In the control system for a turbo-charged diesel aircraft engine, a target value for a fuel injection amount is determined by the stroke of a throttle lever. A boost compensator determines the maximum limit for the fuel injection amount in accordance with the boost pressure of the engine in order to suppress the formation of exhaust smoke. The actual fuel injection amount is set at the target value or the maximum limit whichever is smaller. An electronic control unit (ECU) calculates an increase rate of the stroke of the throttle lever based on an output of the stroke sensor disposed near the throttle lever. The ECU determines that the current operating condition of the aircraft requires a rapid increase in the engine output power when the increase rate of the stroke is larger than a predetermined value and increases the maximum limit determined by the boost compensator.

Abstract: Propeller-driven aircraft (30) comprising an engine (31) providing mechanical engine power for rotating a propeller (32), an engine limiting unit (35), an engine control unit (37) for controlling the mechanical engine power of the engine (31), a system (36) for measuring the airspeed and providing information concerning the airspeed to the engine limiting unit (35), wherein the engine limiting unit (35) automatically reduces the mechanical engine power at airspeeds below a certain first airspeed value (V1).

Abstract: In the control system for a turbo-charged diesel aircraft engine, the engine speed and the fuel injection amount are controlled by a single control lever in such a manner that the engine speed and the fuel injection amount maintain a predetermined fixed relationship in which the fuel injection amount is always smaller than a smoke limit amount. The control system further includes a boost compensator, that restricts the fuel injection amount to a value less than a boost pressure fuel limit determined by the boost pressure of the engine, and an altitude compensator that restricts the fuel injection amount to the value less than an altitude fuel limit.

Abstract: An aircraft control system includes a propeller governor in which a stepper motor is used to apply a compression force on a speeder spring, and a turbocharger in which a stepper motor is used to actuate a needle valve associated with a diaphragm cell. An electronic control unit may be used to control the stepper motor in the propeller governor and the stepper motor in the turbocharger. The integration of the propeller governor and the turbocharger into a single control system decreases the number of individual adjustments that must be performed manually by the pilot.

Abstract: In the control system for a turbo-charged diesel aircraft engine, the engine speed and the fuel injection amount are controlled by a single control lever. However, when the control lever is operated to accelerate the engine, the fuel injection amount immediately increases to the value set by the control lever while the actual speed of the engine requires a relatively long time to reach the set speed. This may cause the actual fuel injection amount to become excessively larger than a value matching the engine speed and to produce exhaust smoke. In order to prevent this problem, the control system includes a delay control device which restricts the rate of increase in the fuel injection amount to a value less than a predetermined maximum value. By restricting the rate of increase in the fuel injection amount, the actual fuel injection amount is maintained at a value matching the actual engine speed during acceleration, and the generation of the exhaust smoke does not occur.

Abstract: A system that allows a boat propeller to maintain a constant blade speed by varying the pitch of the propeller in order to allow the boat's motor to operate at an optimum RPM. The system includes a governor that sends hydraulic fluid to an annular piston, which in turn controls the pitch of the boat propeller blades so that the torque experienced by the engine is kept approximately constant.

Abstract: A wind turbine is configurable with at least one blade is pitched to provide relatively high sensitivity to wind direction or sheer so as to perform a rudder function which moves the blades such that the vertical plane defined by the blade ends is substantially parallel to the wind direction. In one aspect, the wind turbine has at least two different blades having two different blade pitches. In one embodiment, the rudder action configures a two bladed wind turbine such that a non-rudder blade, having a pitch different from the rudder blade, has its free end pointing substantially directly into the wind, providing relatively low cross-sectional resistance to the wind and accordingly relatively low load.

Abstract: A control method for controlling a controllable pitch propeller during gear shifting operations monitors the gear selector switch to determine a future or impending gear shifting operation, determines the current pitch setting of a controllable pitch propeller, saves the current pitch setting, moves the blades of the controllable pitch propeller to a minimal or zero pitch setting, implements the gear change operation, and then returns the blades of the controllable pitch propeller to the original setting or the current setting by minimizing the pitch of the blades of the controllable pitch propeller prior to the shifting operation, the impact shock load on the marine propulsion system can be decreased by minimizing the resistance to propeller hub rotation caused by the blades moving through the water.

Abstract: A control algorithm provides a method for selecting a pitch magnitude for a controllable pitch propeller. The pitch magnitude is selected as a function of the difference between a desired engine speed and an actual engine speed in addition to the actual pitch position of the controllable pitch propeller. The desired engine speed is selected as a function of the position of either a throttle control lever or the throttle plate of an internal combustion engine.

Abstract: Method and apparatus for controlling an aircraft engine with a single, manually-operable lever includes structure and function for generating a pilot thrust command from the single lever. A processor is coupled to the single lever and (i) receives the generated pilot thrust command, (ii) receives a plurality of detected ambient air flight conditions, (iii) receives a plurality of detected engine performance parameters, (iv) determines first and second engine control commands based on the received pilot thrust command, the detected ambient air flight conditions, and the engine performance parameters, and (v) outputs first and second output signals respectively corresponding to the first and second engine control commands. Preferably, the engine control commands comprise propeller RPM and engine inlet manifold air pressure commands, and the detected ambient air flight conditions comprise air speed and altitude.

Abstract: Method and apparatus for controlling an aircraft engine with a single, manually-operable lever includes structure and function for generating a pilot thrust command from the single lever. A processor is coupled to the single lever and (i) receives the generated pilot thrust command, (ii) receives a plurality of detected ambient air flight conditions, (iii) receives a plurality of detected engine performance parameters, (iv) determines first and second engine control commands based on the received pilot thrust command, the detected ambient air flight conditions, and the engine performance parameters, and (v) outputs first and second output signals respectively corresponding to the first and second engine control commands. Preferably, the engine control commands comprise propeller RPM and engine inlet manifold air pressure commands, and the detected ambient air flight conditions comprise air speed and altitude.

Abstract: An engine plant for aircraft comprising a multicylinder internal combustion engine (1) whose crankshaft drives an adjustable pitch propeller (5), mechanisms for adjusting the engine speed and a common power stick (4) that controls the operation of the engine and of the adjustment mechanisms, characterized in that said engine is a compression ignition engine (1) that cooperates with an electronic control system (3) controlling the quantity of the fuel injected.

Abstract: A propeller pitch control apparatus for an aircraft in which the vector sum of the aircraft forward speed and the propeller rotational tip speed is a selected fraction of the speed of sound, the fraction based on percent power and altitude, to maximize efficiency and minimize noise.

Abstract: A control system for an aircraft that controls the set speed of the propeller governor and the degree of opening of the throttle valve using a single control lever. The speed setting mechanism of the propeller governor is directly connected to the power lever by a push and pull cable, and the set speed of the propeller governor changes in proportion to the stroke of the power lever. Therefore, the propeller speed changes in proportion to the stroke of the power lever. On the other hand, the throttle valve is connected to the power lever by a nonlinear cam and a push and pull cable. Therefore, the degree of opening of the throttle valve does not change in proportion to the stroke of the power lever (i.e., the change in the degree of opening of the throttle valve has a nonlinear characteristic), and the engine output power changes in the nonlinear manner with respect to the change in the propeller speed.

Abstract: A synchrophaser for a multi-engine, propeller-driven aircraft including a filter that automatically compensates for misalignment of blade position sensor tabs through derivation and application of a correlation coefficient. The correlation coefficient is calculated in a self-adjustment derivation, utilizing a dynamic tolerance band, providing increased accuracy in propeller speed determination. The correlation coefficient brings about an apparent uniform distribution of blade position sensors, as seen by the synchrophaser, thus eliminating a primary source of cyclic propeller speed disturbances. The correlative filer accomplishes its task without the phase shifting normally encountered in other digital filtering technique.

Abstract: A method and apparatus for controlling a propulsion engine output in a vessel, based on the net axial force on a propeller shaft in the vessel. The apparatus includes a regulating loop with a computer which continuously controls the delivery of fuel to the vessel's engine, and optionally controls the attack angle of the vessel's propeller blades. Control of the fuel delivery is performed in accordance with predetermined control algorithms, and optionally, by operator-set parameter values and maneuvering operations. The apparatus further includes at least one force sensor mounted to a bearing which supports the vessel's propeller shaft. The force sensor, which is preferably mounted to a thrust bearing, detects a net axial force on the propeller shaft. The net axial force detected is then used as a parameter in the control algorithms and therefore as a factor in controlling the delivery of fuel.

Abstract: An engine including a supercharger wherein a waste gate valve is provided in the bypass passage bypassing the exhaust turbine of the supercharger and the supercharged pressure is controlled by the waste gate valve so that when the opening of the throttle valve provided in the intake duct falls under a set level, the air-fuel mixture is made lean and when it becomes greater than the set opening, the air-fuel mixture is made rich. When the air-fuel mixture is changed from a lean to rich mixture, the opening of the waste gate valve is made larger to reduce the supercharged pressure and thereby prevent abrupt fluctuations in the engine output.