Abstract: A propeller control system comprises a phase controller (11) having a phase control gain to control a propeller phase relationship, free air turbulence detection means (7, 9) and a gain controller (8) for varying the phase control gain in response to detected free air turbulence such that in the presence of turbulence a low gain is selected and in the absence of turbulence a high gain is selected. By varying the gain in this way the sensitivity of the phase controller (11) is reduced during turbulent conditions preventing excessive phase changes by the controller (11) striving to follow a turbulent master propeller. Similarly a speed controller (14) has its gain set by a gain controller (17) according to the degree of turbulence detected.

Abstract: An aircraft is maintained at a constant glide slope and air speed by trimming delta torque commands provided by an autopilot. Delta torque commands that change by more than twenty percent are trimmed automatically to maintain the constant glide angle and to assist the pilot in maintaining air speed within .+-.5 knots on the approach glide slope.

Abstract: A torque loop decoupler decouples a torque loop from a speed loop to allow only the speed loop to react to small, rapid changes in engine speed. The torque loop decoupler calculates a compensation signal and adds the compensation signal to a control signal of the torque control loop. The compensation signal keeps the control signal constant during small, rapid changes in engine speed. The compensation signal is calculated as the partial derivative of turbine torque with respect to changes in engine speed multiplied by a signal indicative of small, rapid changes in engine speed.

Abstract: A pitch control apparatus for a variable pitch propeller for drive connection to an aircraft engine, wherein an optimum rotation number of the engine is calculated in relation to a flight speed of the aircraft, an opening degree of the engine throttle and the density of atmospheric air in flight of the aircraft to maximize a thurst force acting on the aircraft, and wherein a pitch angle of the propeller blade is controlled in such a manner that the rotation number of the engine becomes substantially equal to the optimum rotation number.

Abstract: The blade angle controlling pitch beam servo (26) of a helicopter tail rotor (22) is responsive to a main rotor torque signal (92) indicative of torque coupled to a helicopter main rotor (10) for providing torque compensation so that the helicopter airframe will not counter-rotate under the main rotor. The torque coupled to the main rotor is that amount of engine torque (76, 114) in excess of torque coupled to the tail rotor (81, 115) and helicopter auxiliaries (84, 116). The amount of torque compensation provided by the tail rotor is reduced by an amount indicative of aerodynamic forces (130) on the helicopter airframe.

Abstract: Governor stability of a propeller pitch controlled speed governor is improved by dynamically compensating a turbine engine speed error signal employed in determining fuel flow. The fuel flow requirement is a function of the dynamically compensated turbine engine speed error signal, an indicated air speed signal, and a power lever angle signal.

Abstract: A flight-mode propeller overspeed governor and underspeed governor is shown and described. The description includes a reset of the overspeed governor during engine acceleration and a reset of the underspeed governor during engine deceleration to eliminate sluggish transient response in the engine.

Abstract: The invention concerns a control for an aircraft propeller. During operation in reverse pitch, as occurs upon thrust reversal during a landing maneuver, the speed of the propeller is controlled by adjusting pitch of the propeller, in order to prevent overspeeding. Further, during the transition period while the propeller is converting from forward pitch to reverse pitch, the propeller presents a light load to the engine. At this time, fuel flow to the engine is limited in order to restrict delivery of energy to the propeller, again, for the purpose of preventing overspeeding.

Abstract: The pitch of a marine controllable pitch propeller is detected by a motion/DC current transducer in the propeller hub. Circuitry rotating with the propeller shaft converts an AC power signal to DC for energization of the transducer and converts a DC output signal from the transducer to AC. The AC power and output signals are transferred from the rotating circuit to a stationary circuit in the vessel hull by rotary transformers. There are no contacts between relatively moving parts of the transducer or rotary transformers, thus ensuring long life for the pitch detection system.

Abstract: An integrated control system for coaxial counterrotating aircraft propulsors driven by a common gas turbine engine. The system establishes an engine pressure ratio by control of fuel flow and uses the established pressure ratio to set propulsor speed. Propulsor speed is set by adjustment of blade pitch.

Abstract: An integrated control system for coaxial counterrotating aircraft propulsors driven by a common gas turbine engine. The system establishes an engine pressure ratio by control of fuel flow and uses the established pressure ratio to set propulsor speed. Propulsor speed is set by adjustment of blade pitch.

Abstract: An adjusting device is provided for an airplane propulsion system using the reciprocating piston combustion engine and a propeller, which adjusting device simultaneously adjusts the throttle valve and the propeller pitch of the propellers. The adjusting device is formed with a connecting rod and a carrier rod connected thereto. The connecting rod is provided as an adjusting cable whereby the cable core is under spring pretensioning in lower rotational speeds of the motor.

Abstract: The dynamic instabilities in a system which controls prime mover output torque and angular velocity separately are avoided by deriving an accelerating torque signal in an output torque controller where it is added to a sensed torque signal, and the added signal is compared to a commanded torque signal, the difference signal value therebetween serving to control the output torque.

Abstract: A propeller pitch controlling arrangement having a fuel economizer feature for use on marine vessels, has a mode selector valve operable to a normal mode and an economizer mode. In the economizer mode, a first pilot signal is transmitted to a path selector valve to establish a first flow path to a propeller pitch servomechanism. A second pilot signal is transmitted from a relay valve when the marine vessel speed drops below a predetermined value. The second pilot signal moves the path selector valve to a second position establishing a second flow path to the propeller pitch servomechanism. A first selected fluid pressure from a regulating valve arrangement mechanically linked to the engine fuel rack, is directed to the propeller pitch servomechanism when the first flow path is established. This first selected fluid pressure is proportional to the movement to the engine fuel rack.

Abstract: In a propeller pitch control system, a selector 10 isolates engine (42) speed control in one of two engine governor (175 and 300) systems. The selector is input with fluid pressure signals from a pair of pilot valves (215 and 325), each operated by a corresponding one of the governors. The selector passes the signal of lowest magnitude to an actuator 40 which sets blade pitch in accordance with the magnitude of the signal whereby the governor providing such signal (through its associated pilot valve) controls engine speed independently of the other governor.

Abstract: A pitch control system (10) for a variable pitch propeller effects engine governor (330), control of blade pitch under normal operating conditions and automatically effects direct (beta) control of blade pitch by the power lever (305) throughout a predetermined range of power lever settings. The system is hydromechanical and comprises a pitch actuator (40) and a pair of control valves (120 and 210), a first of the valves (120) applying a metered fluid pressure from a governor controlled pilot valve to the actuator and blocking that signal and replacing it with a supply fluid pressure at the point of transition from governor to beta control. The second control valve (210) effects a controlled draining of the actuator and connection thereof with the power lever (305).

Abstract: The blade angle controlling pitch beam servo (26) of a helicopter tail rotor (22) is responsive to a signal manifestation (76) indicative of free turbine engine (20) gas generator speed (78) to provide torque compensation so that the helicopter airframe will not counter-rotate under the main rotor (10) of a helicopter as a consequence of the torque provided thereto by the airframe-mounted engine (20), or in the absence thereof. A trimming embodiment (FIG. 2) provides only sufficient blade angle command (82a) to compensate for that provided by fixed, collective/tail mixing (110-114). Torque compensation tail rotor blade angle commands may be applied through existing stability and autopilot actuators (30-32) or through an additional torque servo (120, FIG. 3).

Abstract: A method of controlling the speed of a ship equipped with a controllable pitch propeller at a predetermined value. A desired horsepower corresponding to a desired ship speed is obtained in accordance with the actual horsepower, the detected ship speed value and the preset ship speed value, and the rpm of the main engine is controlled in accordance with the desired rpm obtained in accordance with an engine loading function generator for minimum fuel consumption obtained in accordance with predetermined engine loading function generator for optimum propeller efficiency and a designed load characteristic function and the desired horsepower. A desired fuel rack position is obtained in accordance with the desired rpm and the desired horsepower and the desired fuel rack position is compared with the actual fuel rack position so as to control the blade angle of the propeller.

Abstract: An overload protection control circuit for marine engines, in which a propeller pitch control signal, as initiated by the operator and transmitted to a servo-positioner for setting the propeller pitch, is modified by a speed control signal, also initiated by the operator, for setting the speed of the ship through a speed governor device, so that the pitch of the propeller is automatically maintained at a degree compatible with the ship speed. According to the invention, an overload limiting valve device is interposed in the protection control circuit and is preset to respond to a critical engine load condition to effect operation of the servo-positioner to a neutral position in which propeller pitch is reduced to a safe degree.

Abstract: The present invention relates to a compound remote control device for controlling the pitch of a variable-pitch propeller on a ship's drive mechanism while at the same time controlling the speed of the ship's engine, and provides a control mechanism for compound control under various control conditions, whereby the conventional equipment being of a complex structure using 2 cams, is simplified by using one cam and a pressure-control valve cooperating therewith. With said control device, control of the speed of the aforesaid engine and the control of the pitch of the variable-pitch propeller are carried out by using air-pressure signals under various control conditions, that is, where the relationship of the various control air pressures in relation to the position of the control lever varies as for example shown in FIG. 1.

Abstract: A regulating system for a prime mover, especially a single-spool gas turbine for use in propelling a motor vehicle or aircraft, in which system there is provided a first speed governor for controlling the fuel flow or input power and a second speed governor for controlling the power output. The two speed governors act concurrently in response to the speed of the prime mover and regulate the power input and power output independently of one another.