Abstract: An arithmetic processing method and system in a wide velocity range flight velocity vector measurement system using a square truncated pyramid-shape five-hole Pitot probe. Approximation equations that determine attack angle &agr; and sideslip angle &bgr; in the form of third-order equations concerning attack angle pressure coefficient C&agr; and sideslip angle pressure coefficient C&bgr;, which are known numbers, are expressed in the form of a polynomial equation concerning Mach number M, where the coefficients are obtained from a lookup table.

Abstract: A method, an apparatus and a computer program product are provided for accurately determining the vertical speed of an aircraft in a manner independent of signals provided by an air data computer, an inertial reference system and an inertial navigation system. Initially, a first vertical velocity of the aircraft is determined based upon a pressure altitude value associated with the aircraft. A second vertical velocity of the aircraft is also obtained from a GPS receiver carried by the aircraft. The first and second vertical velocities are then combined to determine the vertical speed of the aircraft. In this regard, the first and second vertical velocities are combined by complimentarily filtering the first and second vertical velocities. More particularly, the first vertical velocity is typically low pass filtered to remove high frequency noise that is attributable to the relatively low resolution of the first vertical velocity value.

Abstract: Methods and apparatus are disclosed for three-dimensional flight control based generally upon measuring and comparing actual air pressures at or near various surfaces of an aircraft during flight. Sensors are provided for measuring air pressure acting on an aircraft surface. The methods and apparatus include those for measuring air pressure differentials between two or more sensors to evaluate certain critical flight parameters, such as the actual lift being produced, the air direction and speed relative to the aircraft, the air density, and the aircraft position and trajectory. The actual and comparative data provide information about the present flight conditions and performance of the aircraft, such as whether there is ice formed or forming on the wings, the direction and approach of wind shear, whether a stall is approaching, etc.

Abstract: Indicator of a variable for an aircraft. The indicator (1A) according to the invention comprises means (13) for determining first and second target values respectively of a variable and of its derivative with respect to time, and display means (5, 6, 7) which depict on a display screen (7) a means of indication (14) of the first target value, which is arranged in such a way as to indicate this first target value on a graduated scale (8), and a means of indication (16B) of the second target value which is associated at least with an indicator element (11) indicating said derivative so that, when the latter points toward said means of indication (16B), said variable of the aircraft becomes equal to and remains equal to said first target value and said derivative is equal to said second target value.

Abstract: Disclosed are avionics systems and methods of using the same to monitor a pitot-static system for blockages. A first aircraft movement rate is calculated as a function of a pressure sensed using the pitot-static system. A reference movement rate is calculated using an independent navigation system such as an inertial reference system, a global positioning system, or an attitude heading reference system. The calculated first aircraft movement rate is compared to the calculated reference movement rate to determine whether the calculated first aircraft movement rate falls within a predetermined tolerance range about the calculated reference movement rate. If the calculated first aircraft movement rate falls outside of the predetermined tolerance range about the calculated reference aircraft movement rate, it is determined that a blockage exists in at least one of a pitot tube or a static port of the pitot-static system.

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: A broad-range, multi-directional aircraft airspeed measuring system is provided. The airspeed measuring system has multiple vortex generating probes located within a venturi section. At least one rearward facing probe and one forward facing probe are included. Additional probes can be added to extend the high speed range of the airspeed indicator. A splitter plate or plates separate flow channels from each other to provide a separate flow channel for each vortex probe. Each vortex probe has a hot film sensor and anemometer.

Abstract: In a rotary wing aircraft, longitudinal groundspeed error and lateral groundspeed error are converted to earth coordinates, and the result scaled and integrated, and retransformed into aircraft coordinates for application to a pitch attitude control system and a roll attitude control system. The invention thus instantly transfers wind trim between the longitudinal and lateral channels, whenever a heading change is undertaken.

Abstract: A process for managing air speed of an aircraft in flight. The method includes a first step of determining a point on the flight path at which it is theoretically possible to comply with a required time constraint by following a pre-established speed profile. In a second step, a speed is computed and a fresh speed profile is determined. This is obtained by determining speed corrections segment-by-segment from the point up to the last modifiable segment. The speed change in each segment is restricted to a maximum value. The new speed is computed on the basis of the curve showing the flight time t as a function of the speed V. This curve is approximated by a curve satisfying an equation with three coefficients (C.sub.1, C.sub.2, C.sub.3):V=c.sub.1 /t+c.sub.2 /t.sup.2 +c.sub.3 /t.sup.3Compliance with time constraints are ensured by this method while meeting the requirements of the pilot and air traffic controllers.

Abstract: The airspeed limiting performance envelope of a helicopter is converted to a groundspeed envelope by factoring-in the wind speed and direction. A groundspeed command for an unmanned helicopter is provided as a function of the range to the helicopter's destination. The function may be calculated so as to provide a nominal groundspeed command equal to a nominal groundspeed command limit, or the function may be a fixed function to cause the aircraft to creep toward final approach. The cosine and sine of the desired relative flight direction of the aircraft, which is equal to the true bearing to the destination minus the true heading of the aircraft, are utilized to scale the groundspeed command into a longitudinal groundspeed command and a lateral groundspeed command. If one of the groundspeed commands is over a corresponding limit, the other groundspeed command is scaled back so that the vector addition of the two commands will cause flight in the desired direction.

Abstract: A bowthruster is operated by a control unit with wind direction based on a detection signal from vane-anemometer. A bow in a hull attitude is slightly adjusted so as to direct a bow of the hull to windward. At the same time, a propulsion unit is operated by control unit in accordance with wind strength based on a detection signal from vane-anemometer. A hull position is slightly adjusted such that the hull is moved based on a distance carried away by wind. Rocking of the hull is reduced by always directing the bow to windward and also the hull is stayed at a constant point located directly over shoal of fish or gathering place for fish so as to enable the pleasant fishing. Accordingly, because of good control response and fine ship position adjustment, the hull is positioned quickly in a fishery and then maintained at a predetermined point in the fishery.

Abstract: A method and apparatus for measuring the lift generated by airfoils of an aircraft. This real-time analysis is accomplished by measuring a differential pressure between the upper and lower lift surfaces of the airfoils. The system comprises the steps of: a) measuring an actual differential pressure between the upper and lower lift surfaces for a given aircraft speed, b) transmitting this actual differential pressure measurement to a computer, c) comparing the actual differential pressure measurement with an optimal pressure differential for the same aircraft speed. The apparatus comprises a fixed array of differential pressure sensor mechanisms for measuring actual pressure differentials and a computer for comparing optimal differential pressure measurements to the actual differential pressure measurements. Each sensor mechanism preferably contains a piezoelectric sensor that communicates with the upper and lower lift surfaces.

Abstract: The disclosed flight control system includes a rotor blade speed monitor for monitoring the rotor blade speed of the jet powered tri-mode aircraft and for outputting a rotor blade speed command. The flight control system also includes an aircraft attitude controller for controlling the aircraft attitude of the jet powered tri-mode aircraft. Weighted rotor blade attitude stabilization commands and weighted aero surface attitude stabilization commands are output from the aircraft attitude controller to distribute power, control, and lift between the rotor blade and the aero surfaces. Relative weights of the weighted rotor blade attitude stabilization commands decrease with increasing aircraft travelling velocities, and relative weights of the weighted aero surface attitude stabilization commands increase with increasing velocities.

Abstract: The present invention provides a device for indicating an operating point of an aircraft comprising a sensor to measure air speed and a sensor to measure vertical acceleration. The device also comprises a processor in communicative connection with each of the airspeed sensor and the vertical acceleration sensor. The processor is also in communicative connection with a display. The display presents an operating envelope diagram of the aircraft. The display also displays the current operating point of the aircraft relative to the operating envelope diagram. The present invention also provides a method for indicating an operating point of an aircraft in which the operating envelope diagram and the measured operating point of the aircraft are displayed upon the same display.

Abstract: The invention is directed to means, utilizing a neural network, for estimating helicopter airspeed at speeds below about 50 knots using only fixed system parameters as inputs to the neural network.

Abstract: An apparatus for compensating for spatial phase angle phase errors in the flapping angle oscillations of a rotor blade is disclosed. The apparatus receives a measured aircraft roll and a measured aircraft pitch. Gyroscopic moments resulting from these measured rolls and pitches are determined, and compensating gyroscopic moments are then generated and summed with commanded pitch and roll accelerations. Flapping angle phase lags of the rotor blade swashplate are added to the summed signals to cancel any flapping angle phase leads, caused by changes in aircraft or rotor blade speed caused by installation configurations of the rotor blade swashplate.

Abstract: An air active control aircraft having an air three-dimensional true airspeed detection system composed of an air data sensor probe in the form of a truncated pyramid-shape Pitot probe and an air flight velocity operation processor for calculating an air flight velocity vector from three-dimensional air pressure information detected by the air data sensor probe, airframe motion detection sensors for detecting an airframe motion, and an on-board control computer for generating a flight control law. The on-board control computer inputs an air flight velocity vector signal obtained from the air flight velocity vector device into a control-surface control system in parallel with airframe motion detection sensor signals, and presumes a flight motion induced by a change in air to generate the flight control law for quickly carrying out air flight stability control.