Abstract: In an adaptive speed control system for a vehicle, a method and system for controlling vehicle deceleration are provided. The method includes determining a speed of the vehicle, and setting a maximum allowed vehicle deceleration based on the vehicle speed determined. The system includes a receiver capable of receiving an input signal indicative of a speed of the vehicle, and a controller capable of setting a maximum allowed vehicle deceleration based on the vehicle speed.

Abstract: A method augmenting a pilot's command lane signal by transmitting the pilot's input command to a first summer and the surface actuator control circuitry. The first summer output signal is transmitted to a second summer circuit to add (or subtract) the first summer output signal with a flight control signal resulting in a second summer output signal. The second summer output signal is transmitted to the first summer to add, subtract or otherwise modify the second summer output signal with the pilot command input signal. Thus, the pilot command input signal is augmented or coupled with the second summer output signal to provide better control of the aircraft while not allowing the flight control computer/avionics control electronic circuitry to directly augment the pilot command input signal.

Abstract: An apparatus, method and computer program product has a first terrain awareness mode and a second terrain awareness mode selectable by the pilot.

Abstract: A method, apparatus and computer program product for alerting the pilot of a helicopter of a possible tail strike hazard.

Abstract: The present invention includes a system, method and computer program product for reducing nuisance warnings during low performance takeoff conditions. The system includes a first component that determines aircraft current climb rate and potential climb rate based on aircraft vertical speed data and velocity information and a second component that adds the determined current climb rate and potential climb rate. The system also includes a third component that disables alerts, if the sum of the current climb rate and potential climb rate differ from a predetermined climb rate by a threshold amount and if the aircraft is supposed to be in a maximum thrust condition (e.g. takeoff, missed approach).

Abstract: The angle of attack of an airfoil moving through the air can be detected and a display provided electronically through use of an all-solid-state system powered by a D.C. source. A wind vane mounted on one end of a shaft is exposed to the airflow while a windowed mask is provided at the other end of the shaft. By providing an appropriate array of openings in the mask, and a series of associated optical transmitters and receivers on opposed sides of the mask, extremely fine sensitivity can be provided in detection of angle of rotation of the mask and thus in the angle of rotation of the vane. The angle of the vane is directly established by the angle of attack. The detected angle of attack is then displayed on a vertically oriented light bar on the instrument panel, for instance in a light aircraft.

Abstract: An apparatus, methods, and computer program products are provided for monitoring the attitude of an aircraft. The apparatus of the present invention includes a navigation system, such as a GPS, that provide values representing the velocity vector of the aircraft. Additionally, the apparatus includes two gyroscopes positioned with respect to the aircraft to sense the roll and pitch of the aircraft. A generator is connected to the navigation system and generates a calculated flight path and roll angle based on the velocity vector of the aircraft. Further, the apparatus of the present invention includes a combiner connected to both the generator and the gyroscopes. The combiner combines the calculated flight path angle to the sensed pitch angle and the calculated roll angle to the sensed roll angle and generates composite flight path and roll angles. The composite flight path and roll angles represent the attitude of the aircraft.

Abstract: In an adaptive vehicle speed control system, a method and system for controlling the speed of the vehicle while the vehicle is traversing a curved path. The method and system include sensing the yaw rate of the vehicle, determining the yaw acceleration based on the yaw rate, and determining a maximum allowed speed of the vehicle on the curved path based on the yaw rate and the yaw acceleration. The method and system also include limiting the speed of the vehicle on the curved path to a value no greater than the maximum allowed vehicle speed.

Abstract: An apparatus, method and computer program product useful for supplying the pilot of an aircraft with aircraft attitude information. During bank angles exceeding a predefined limit, the roll gyro is slaved to a roll angle estimator for improved system accuracy.

Abstract: An apparatus, method and computer program product useful for supplying the pilot of an aircraft with aircraft attitude information in the event of full or partial failure of the gyroscopic system normally used to supply such data. The pitch angle, roll angle and heading angle estimates provided by the apparatus, method and computer program product can be displayed to the pilot thereby alleviating the requirement that the pilot mentally integrate such data from the remaining aircraft instruments.

Abstract: The invention discloses a method of preventing potentially hazardously misleading attitude data. The method includes deriving a value for a leveling parameter from inertial and velocity data, monitoring the leveling parameter for a characteristic indicative of producing potentially hazardously misleading attitude data, and disregarding at least some air data if the characteristic is detected. The computer readable medium contains instructions to cause an attitude heading computer to perform the steps of (1) deriving a leveling parameter from velocity data and inertial data; (2) monitoring the leveling parameter for a characteristic indicative of producing hazardously misleading attitude data; and (3) not accounting for at least some velocity data in leveling algorithms if the characteristic is detected. The invention also includes a second embodiment of a method of preventing potentially hazardously misleading attitude data.

Abstract: Aircraft tail strike protection is provided by displaying to a pilot tail strike warning symbols during takeoff and approach to landing. In a takeoff scenario, a pitch margin indicator symbol referenced to a boresight symbol provides a pilot with anticipatory information and an awareness of the pitch attitude margin before a tail strike incident. In an approach to landing scenario, a TAILSTRIKE warning annunciation is referenced to a flight path symbol and alerts the pilot of an impending tail strike incident. The symbols displayed during either scenario center on the pilot area of focus for each task. They give the pilot an awareness of an impending tail strike incident and necessary reaction time to avoid it.

Abstract: A system for supporting a fire fighting for a building and a fire fighting method using the same which are capable of more effectively performing a fire fighting operation by providing, in real time.

Abstract: An apparatus for determining the bank angle of an aircraft and method includes a receiver for receiving navigational signals from NAVSTAR/GPS satellites in orbit about the earth, a signal processor for demodulating the satellite navigational signals, an arrangement for determining a sensitivity value, the sensitivity value being defined as the amount of bank angle displayed per rate of change of track heading, an arrangement for determining the rate of change of the aircraft track heading from the navigational signals, an arrangement for determining the bank angle of the moving aircraft from the sensitivity value.

Abstract: The present invention relates to a method 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 the aircraft surface. The method includes 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 if 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. The information can be evaluated by a computer, the aircraft's automatic flight control system ("AFCS"), or flight crew so that appropriate flight control measures can be taken.

Abstract: An 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 apparatus a) measures an actual differential pressure between the upper and lower lift surfaces for a given aircraft speed, b) transmits this actual differential pressure measurement to a computer, c) compares the actual differential pressure measurement with an optimal pressure differential for the same aircraft speed, and d) evaluates performance of the aircraft based on the result of the comparison. 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: A spatial disorientation detector system capable of warning a pilot of potentially disorienting flight conditions in response to Kalman filter modeling of human response characteristics. The Kalman filter models are representative of human semicircular canal and otolith responses and are capable of more accurate prediction of actual pilot disorientation conditions than are systems which respond with simple magnitude measurement of disorientation stress. Examples of disorienting environments are also disclosed.

Abstract: The disclosure is an aircraft collision-avoidance device used notably during landing approach. The device includes at least means of fixing the position of the aircraft, a database, first means of comparison, means of extraction of the point of touch-down on the runway, means of calculating the real glide slope vector of the aircraft, means of extraction of the theoretical glide slope vector of the aircraft, and second means of comparison used to compare the real and theoretical slope vectors. It is applicable in particular to airliners during final approach to landing.

Abstract: A ground proximity warning system and a detector for aircraft having fixed or non-retractable landing gear which rather accurately detects a landing phase of flight in order to adjust the warning envelope to minimize nuisance warnings during such a phase of flight. In particular, the system monitors the flap position to provide an indication to the ground proximity warning system that the aircraft is either in an approach, cruise or landing phase of flight. Cams mounted to the air flaps system indicate a landing phase of flight when the approach flaps are configured for a normal landing, such as 16.degree.-18.degree. flaps or an approach phase of flight when the flaps are configured for a normal approach, for example, 5.degree.-7.degree. flaps. By providing a relatively accurate indication of the phase of flight for an aircraft with non-retractable landing gear, nuisance alarms will be virtually eliminated, while maximum protection is provided during all phases of flight.

Abstract: A windshear guidance system for guiding an aircraft during a microburst windshear is provided. This system includes a time comparison subassembly, an airspeed comparison subassembly and a pitch command subassembly. The pitch command subassembly includes a calibrated air speed source, latch means connected to the calibrated air speed source, switch means connected to the latch means, and a pitch guidance command unit connected to the switch means.

Abstract: A digital rebalance system for an inertial reference sensor. The rebalance system associates the error signal output with a sample value of a stored error signal and generates a rebalancing torquing pattern waveform in response to the error signal. The system includes waveform generation and error signal processing devices, precision timing devices, passive compensation circuitry and a precision switching circuit.

Abstract: A low airspeed alerting system for alerting the pilot of an aircraft of insufficient airspeed during a landing monitors various readily available signals representative of flight parameters of an aircraft such as pitch angle, vertical speed and true airspeed and advises the pilot when the airspeed of the aircraft is approaching an airspeed (kinetic energy) that is too low with respect to the ground to maintain the aircraft flying along the desired flight path without stalling, or without action by the pilot in time to recover.

Abstract: Performance of an aircraft ground proximity warning system can be improved, especially where the performance of the aircraft itself has been degraded by a factor such as wind shear, by extending Mode 1 and Mode 3 warning envelopes down to within five feet of the ground. Additional improvements in warnings can be made by monitoring flight path angle, stall margin, angle of attack and deceleration profile, when the aircraft is close to the ground.

Abstract: A ground proximity warning system monitors the flight path angle or barometric or inertially derived descent rate of the aircraft and modulates the glide slope alerting function in accordance with flight path angle or descent rate when the aircraft is not descending rapidly even though it is below the glide slope in order to reduce nuisance warnings without compromising system sensitivity. Alternatively, the repetition rate of the alert may be varied as a function of the flight path angle or descent rate to provide less frequent alerts when the aircraft is not descending rapidly.

Abstract: An aircraft performance monitor 1 receives signals representative of the height h, rate of change of height h and vertical acceleration .theta. of the aircraft. The monitor 1 determines when (h-A(.sub.n.sbsb.1.sup.n.sbsp.2 +K.sub.1 h+K.sub.2 .theta. goes beyond a predetermined limit and generates a warning signal and disables the autopilot. The signal representative of vertical acceleration may be derived from the rate of change of pitch attitude of the aircraft, from the elevator angle or from an accelerometer.

Abstract: A ground proximity warning system for aircraft having flight path angle based warning criteria generates a warning in the event of an excessively steep flight path angle during an approach to a landing. The warning criteria are altered to provide an earlier warning upon the occurrence of a low intensity wind shear or a below glideslope condition. A below glideslope warning system that is biased as a function of decreasing performance shear is also provided. A descent rate based warning system usable above a predetermined altitude may also be provided to supplement the flight path angle warning system.

Abstract: An improved aerodynamic vane is used for sensing the angle of attack of an aircraft during yawed flight. Left and right sensors are rotatably mounted to opposite sides of the fuselage of the aircraft and rotate in the air flow to a position indicative of the angle of attack of the aircraft. Each sensor consists of an arm rotatably attached at one end to the aircraft with a vane at the other end of the arm, which vane is canted at an angle with respect to the axis of rotation of the arm. The vanes on the sensors on the opposite sides of the aircraft are both canted down or up as to cause the sensors to take similar angular positions during yawed flight.

Abstract: Disclosed is a method of and an arrangement for generating a ground effects compensated aircraft body angle of attack signal. The disclosed method includes converting an aircraft pitch rate corrected alpha vane signal to a free air body angle of attack signal that is calibrated to the type of aircraft that employs the invention for the two conventional landing flap settings. The free air body angle of attack signal then is processed to obtain an alpha vane correction signal that represents ground effects compensation that would be required at zero altitude (aircraft touchdown). The zero altitude alpha vane correction signal is then multipled by an altitude scaling signal and converted to a ground effects compensation signal that is applicable to the then current altitude of the aircraft. The ground effects compensation signal then is summed with the free air corrected body angle of attach signal to provide the ground effects compensated body angle of attack signal of the invention.

Abstract: A canard based air speed, angle of attack and sideslip measurement system consisting of canard mounted pressure transducers. The canard includes a leading edge, a side surface, a bottom surface and a top surface. The apparatus includes pressure sensors including a plurality of flush orifice pressure sensors mounted on the canard further including a first configuration of pressure sensors flush mounted on the side surface, a second configuration of pressure sensors flush mounted on the bottom surface, a third configuration of pressure sensors mounted on the top surface, and a fourth configuration of pressure sensors mounted on the leading edge and wherein each pressure sensors provides an output signal and the combinations of all of the output signals are proportional to the angles of attack of the aircraft. A shaft encoder provides displacement angles for the canard.

Abstract: A stall warning "stick shaker" reference level signal is produced as a function of both flap position and total aircraft thrust. More specifically, a correction term .DELTA..alpha. is combined with a standard stick shaker reference level signal which is scheduled as a function of aircraft flap position. The .DELTA..alpha. signal is scheduled as a function of the total aircraft gross thrust coefficient. The resultant reference level signal produces advance stall warnings that are essentially invariant with engine power level.

Abstract: A display device for use as an attitude display in an aircraft comprising a circular array (5) of selectively activatable display elements, the elements being disposed in equally angularly spaced radially extending lines, each line having the same number of elements with corresponding elements in the different lines at the same radial distance from the center of the array (5); and a controller (3) for selectively activating said display elements in accordance with aircraft attitude whereby the selected elements form a visible pattern indicative of the aircraft attitude.

Abstract: Device for visualizing failures for gyroscopic instruments comprising, inendently of the size of the indicator which incorporates it, an intuitive warning means accounting simultaneously for the supply of the liability and for the speed conformity of the gyroscope to the required values. It comprises two complementary display zones in the rolling dial (5 and 6) made up by means of elements of liquid crystals presenting an opaque appearance in the presence of a supply voltage and showing a color required in the absence of a supply voltage. One of the zones (5) is comprised of a single active element informing of the disappearance of the supply while the other zone (6) is comprised of a plurality of juxtaposed active elements, which are progressively switched and which give a synoptic perception of the speed reduction of the gyroscopic top of the instrument.

Abstract: An improved windshear warning apparatus for aircraft, responsive to both the magnitude of the wind shear and the allowable time the windshear can be tolerated at a given magnitude. The sensed magnitude is used to compute the allowable time before providing a windshear alarm. For large windshear rates, the allowable time is short; conversely for small windshear rates which exceed a threshold level, a longer time period is computed before an alarm occurs. Since a windshear rate must persist for the computed allowable time before activating the alarm, windshear rates that are above the threshold level for elapsed time less than the computed allowable time will not result in an enunciation, while high magnitude windshear rates of short duration will not cause false alarms since they do not exceed the computed allowable time.

Abstract: A system for warning the pilot when the aircraft has reached a high yaw condition. A differential in pressure or angle of attack between the port and starboard sides of the aircraft is measured and converted into a measured sideslip angle. If the measured sideslip angle exceeds a predetermined maximum acceptable sideslip angle, a warning device, such as a rudder pedal shaker, is activated. The maximum acceptable sideslip angle is determined as a function of the ability of the aircraft flight controls to counteract a rolling moment generated by the yaw condition.

Abstract: Method and apparatus for commanding an optimal flight path for an aircraft encountering a windshear condition. An airspeed rate signal equal in magnitude and opposite in sense to the windshear is applied to derive a variable rate of change of airspeed command for application to a flight director indicator. Limits are placed on the derived command such that the minimum allowable speed command is stick shaker speed and the maximum allowable speed command is the nominal speed in the absence of the windshear. The resultant command signal represents a true airspeed rate that yields an optimal flight path for the aircraft to exit the windshear condition.

Abstract: An aircraft performance instrument which provides a first indicator which represents the line of level flight of the aircraft and a second indicator representative of the maximum permissible angle of attack of the aircraft.

Abstract: A system for warning the pilot of a rotary wing aircraft such as a helicopter of a flight condition that, if left uncorrected, would result in the tail of the aircraft striking the ground monitors the altitude above ground, descent rate, pitch and pitch rate of the aircraft and provides a warning if the relationship between the aforementioned parameters is such that a tail strike is imminent.

Abstract: The invention provides for rapid response and reliable detection of vertical windshear during the takeoff and approach phases of flight. Standard instrumentation available on many aircraft is used to calculate the down-draft acceleration and its effect on the aircraft's performance capability. The invention utilizes inputs from vertical acceleration, true airspeed, pitch angle, and angle of attack sensors. The rate of change of vertical wind is derived from the sensed signals and used to determine the margin between the aircraft's present performance capability and the predicted performance capability at stick shaker speed.

Abstract: A wind shear detection and alerting system (30) compares inertially derived accelerations with air speed rate to provide a wind shear warning signal. Inertially derived accelerations are used instead of purely inertial accelerations because purely inertial systems generally require a vertical gyro. By utilizing angle of attack (.alpha.) and flight path angle (.gamma.) instead of pitch angle (.theta.) in the calculation, no vertical gyro signal is required and the system will be responsive to vertical as well as horizontal shear conditions. An enhanced version of the system is also compensated for roll angle (.phi.), with the roll angle being derived from the rate of change of heading (.PSI.) to avoid the need for a vertical gyro. The alerting system is capable of providing visual and aural warnings for a variety of wind shear conditions, such as, head shear, tail shear, head shear followed by tail shear and wind shear trend.

Abstract: An aircraft ground proximity warning system having an excessive terrain closure warning mode and a below glide slope warning mode monitors the glide slope signal and modifies the terrain closure warning envelope to accept a lesser terrain clearance when the aircraft is within the glide slope beam.

Abstract: The difference in dynamic pressure in the propeller slipstreams as measured by sensors 20 and 20a is divided by the freestream dynamic pressure generating a quantity proportional to the differential thrust coefficient. This quantity is used to command an electric trim motor 26 to change the position of trim tab 14 thereby retrimming the airplane to the new asymmetric power condition. The change in position of the trim tab produced by the electric trim motor is summed with the pilot's input to produce the actual trim tab position.

Abstract: A windshear warning apparatus which separately compares a plurality of signals derived from horizontal and vertical inertial acceleration and air mass acceleration components to indicate incipient windshear. The compared signals are substantially equal under normal wind conditions but are significantly different under windshear conditions. A signal proportional to the product of the magnitude and rate of change of the total or resultant inertial acceleration of the aircraft is used to provide a warning of a significant windshear condition.

Abstract: A solid state attitude and director indicator (ADI) is disclosed utilizing liquid crystal display technology to represent attitude of a vehicle in two axes. A visual representation of attitude changes is provided on the liquid crystal display as well as numeric data, in a preferred embodiment. Additionally, glideslope, localizer, and approach speed may be displayed as well as heading and command bar information.

Abstract: In order to reduce nuisance warnings and to increase the effectiveness of real warnings produced by a ground proximity warning system, the criteria for generating a warning is varied for certain airport areas to take into account the terrain in those areas. Along with position data, certain flight parameters such as heading, altitude, glideslope and localizer deviation are checked by the system in order to ensure that the aircraft is located in the desired warning modification area. In addition, the ground proximity warning system includes a mechanism for ensuring that the corrected barometric altitude of the aircraft is within acceptable limits.

Abstract: A heading reference system (100) for sensing vehicle heading relative to fixed inertial space is mountable in a vehicle such as a land-based vehicle and includes a two-degree-of-freedom (TDF) dynamically tuned gyroscope (150) responsive to vehicle rotation about pitch and yaw axes for generating rate signals indicative of the rotation. A caging loop (160) generates force signals for torquing the gyroscope (150) to a null position. A pair of accelerometers (186, 187) are responsive to misalignment of the vehicle relative to a horizontal plane formed by the pitch and roll axes. Processor circuitry (180) is responsive to the force signals, the misalignment of the vehicle relative to pitch and roll axes, and distance signals generated by an odometer unit (140) to apply heading signals to an indicator unit (120) for visually indicating to a vehicle operator the directional heading.

Abstract: A system for tactilely alerting an aircraft pilot that the aircraft is in an uncoordinated turn condition and for indicating to the pilot the control adjustments required to correct the turn condition. The system includes a device for sensing the turn condition of the aircraft and a pair of tactile sensation generators in the vicinity of the pilot's legs. The condition sensing device controls activation of one or the other of the tactile sensation generators which indicates to the pilot which foot to depress on the rudder control to return to coordinated flight.

Abstract: This system permits speed variation within certain constraints. The minimum speed is derived from a stall avoidance or acceleration margin condition and the maximum speed may be the lower limit of the transonic region or other design limit. Assuming the throttle is set at or near a trim value, adjustments need only be made if the terrain following flight path is tending to drive the speed to one of the two velocity extremes. Velocity predictions are based on predicted kinetic energy being equal to the difference between the current kinetic energy and the potential energy to the profile extreme. The throttle is adjusted when the predicted velocity is outside the limits to add or remove the required amount of energy.