Abstract: A novel and non-trivial system and methods for displaying partial images and non-overlapping images acquired by vision systems representing scene is disclosed. A system is disclosed for displaying partial images and shared, non-overlapping images on a display comprises a forward-looking imaging device system, an image system, a terrain rendering processor, and an indicating system. The terrain rendering processor determines, based on visibility data, which part of an image of one system will be displayed. A method is disclosed for displaying a partial image on a display unit. A terrain rendering processor determines acceptable and unacceptable visibility data based on contrast data of first image data, and based on such determination, presents image data corresponding to unacceptable data to the indicating system for presentation on a display unit. A second method is disclosed for displaying two images on a display unit of an aircraft.

Abstract: The field of the invention is that of securing the necessary piloting information for aircraft cockpits. The invention relates to a head-up display for aircraft, characterized in that it comprises means of calculating a “PFD” type symbology comprising at least the speed, altitude and attitude information, the display symbology being able to be specifically adapted to cope with cockpit smoke or fire conditions.

Abstract: One embodiment of the present invention includes an aircraft instrumentation system for a cockpit instrument panel having a first device associated with a first pilot of an aircraft and positioned on the instrument panel substantially in front of the first pilot. The first device may include a first display and a first controller, which may have a set of controls for controlling the first display and aircraft systems. The instrumentation system may also include a second device associated with a second pilot of the aircraft and positioned on the instrument panel substantially in front of the second pilot. The second device may include a second display and a second controller, which may have a set of controls for controlling the second display and the aircraft systems. The instrumentation may be configured such that at least one of the first display and the second display presents attitude, altitude and airspeed at all times.

Abstract: A method is disclosed for checking model planes entering into a dive, as well as an anti-dive method and apparatus. The method of checking planes includes installation of a first optical sensor in the upper part of the plane, with installation angle upwardly intersecting with the front of the plane at ? degrees, that checks light intensity and outputs a first checked optical signal; installation of a second optical sensor in the bottom part of the plane, with its installation angle downwardly intersecting with the back of the plane at ? degrees, which checks light intensity and outputs a second checked optical signal. A comparison is made between the first and second checked optical signals, and when the difference in light intensity is smaller than a threshold, a warning signal is sent out indicating that the plane has entered into a dive.

Abstract: A radio frequency identification (RFID) system having the capacity to detect conditions of alignment, wherein the system may be used with hand-held, fixed-in-place, stationary, and permanently mounted apparatus. The system includes an RF interrogator configured for use with dental x-ray, medical imaging, film, and digital radiography apparatus, and may include a multiplicity of RF transponders or interrogators. An RF interrogator, an RF transponder, and an x-ray sensitive imaging device, and its holder are configured to be critically aligned to a dental x-ray machine head apparatus, rendering repeat imaging unnecessary. The x-ray emitter may be further configured to automatically obtain a desired x-ray image or configured so that the device cannot activate and provide a radiograph until alignment with the transponder and associated x-ray sensitive imaging device has occurred.

Abstract: An auditory attitude indicator for aircraft that includes an audio source providing an audible signal, a? stereo headset with a left side and a right side, an aircraft avionics system that provides at least aircraft pitch data and roll data to an audio processor unit. The audio processor unit includes at least one lookup table of coefficients corresponding to a plurality of possible aircraft pitch and roll orientations and at least two selectable multipoint finite impulse response filters. The first selectable multipoint finite impulse response filter having a first coefficient selected by the audio processing unit from the lookup table based upon the aircraft pitch data and roll data for varying the audible signal to the stereo headset left side. The second selectable multipoint impulse response filter for varying the audible signal to the stereo headset right side having a second coefficient selected by the audio processing unit from the lookup table based upon the aircraft pitch data and roll data.

Abstract: The flight display includes a vertical terrain profile display having a format that includes a side-on vertical terrain profile comprising a plurality of color filled vertical alerting bands representing areas of terrain that are within defined limits above and below the airplane altitude. A symbol is positioned relative to the side-on vertical terrain profile for representing an altitude and position of the aircraft. Displays of range and altitude are positioned relative to the symbol and side-on vertical terrain profile in predetermined increments. In another broad aspect the side-on vertical terrain profile includes a plurality of color filled horizontal absolute altitude bands representing the absolute altitude of the terrain. These displays may be accompanied by nested color filled blocks representing weather hazards and/or terrain alerting prediction icons.

Abstract: Methods and apparatus are provided for airspace navigation. Airspace navigation information for an aircraft is displayed in a first mode, such as, in a horizontal mode. One or more navigation events may then be detected, such as, proximity to a terrain feature, weather, traffic etc. The airspace navigation information for the aircraft is then displayed using dual modes, e.g., a horizontal mode and a vertical mode. Display parameters, such as colors, resolution, distance, scale, etc. may be set automatically or by a user. The display may also include information, such as avionics systems information, and communications information.

Abstract: This invention relates to the concept of managing the rate of change of energy in a helicopter or other aeronautical vehicle. The invention uses energy management calculations to determine the maximum longitudinal and lateral inputs that can be made while still enabling the vehicle to maintain a desired vertical state. The results of the calculations can be cued to the pilot either tactilely, aurally, or visually, or used for internal software limiting.

Abstract: Systems and methods are provided for determining a final heading of a turning vehicle, such as a rotorcraft. The system may include an algorithm that calculates an advance prediction of a final heading that will be achieved after control input is terminated. The system may also include a device, such as a display, for conveying predicted final heading information to an aircraft controller, such as a pilot.

Abstract: A static longitudinal stability (SLS) system provides an unobtrusive airspeed hold function that reacts to the pilot control inputs into the flight control system and the measured states of the aircraft to engage and disengage smoothly without any explicit mode selection by the pilot. The SLS engages airspeed hold when the aircraft is close to trimmed, non-accelerating state. This logic allows the pilot to either fly close to a desired airspeed and let SLS engage, or trim the aircraft in an accelerating/decelerating maneuver and just wait for the SLS to capture a speed when longitudinal acceleration is small. The SLS is not dependant on the pilot specifically selecting this mode, but rather engages and disengages in response to flight control system status and how the aircraft is being maneuvered.

Abstract: A method of dynamically displaying lateral deviation in formats on a display is provided. The method comprises assigning one or more positional boundaries for displaying the lateral deviation information, wherein the one or more positional boundaries define areas on a display. The method also comprises calculating display positions of a lateral deviation symbology and determining if each calculated display position is allowed based on where the lateral deviation display would be located, if displayed at each calculated position, in relation to the one or more positional boundaries. The method further comprises, displaying the lateral deviation symbology at the calculated positions when the calculated positions are allowed, and displaying a lateral deviation indicator when the calculated positions are not allowed.

Abstract: Methods and systems are provided for displaying an unusual attitude of an aircraft in a head-up display system. The system comprises a projection unit configured to project the unusual attitude of the aircraft and a processor coupled to the LCD projection unit. The processor is configured to control the LCD projection unit during the unusual attitude of the aircraft to produce an attitude indicator of the aircraft and a horizon symbol. The horizon symbol divides the attitude indicator into a first region having a first display characteristic and a second region having a second display characteristic different from the first display characteristic. The first display characteristic is substantially uniform throughout the first region, and the first region indicates a ground with respect to the aircraft.

Abstract: Embodiments of the present invention provide a method of dynamically transitioning into a distinct display format during unusual attitude conditions. In one embodiment, the method includes collecting attitude data, comparing current attitude to a first set attitude angle, and fading a distinct display format into a display for unusual attitude conditions when current attitude is at least equal to the first set attitude angle.

Abstract: The invention relates to a method and system for supporting pilots in landing helicopters in visual flight under brownout or whiteout conditions. According to the invention, 3D data of the planned landing site are generated during the approach for landing, and are accumulated into a 3D representation of the landing site with the aid of position and attitude data of the helicopter. From this 3D representation, a virtual external view is continuously generated corresponding to the perspective of the actual position and attitude of the helicopter and is displayed for the pilot. A control routine ensures that no 3D data of the planned landing site that are generated under brownout or whiteout conditions are taken into account in the accumulation of the 3D representation.

Abstract: Methods and apparatus are provided for displaying terrain and attitude data symbology for an aircraft. The apparatus is a hybrid centered head-down display for an aircraft having a monitor configured to generate a display and a processor coupled to the display. The display has a centerline. The processor is configured to calculate a displayed drift angle limit, a displayed drift angle, align the centerline of the display with reference to the displayed drift angle, and generate on the display a first symbol corresponding to a terrain and a second symbol corresponding to an attitude of the aircraft. The processor is further configured to center the first symbol and the second symbol with reference to the centerline.

Abstract: A manufacturing process of a semiconductor piezoresistive accelerometer includes the steps of: providing a wafer of semiconductor material; providing a membrane in the wafer over a cavity; rigidly coupling an inertial mass to the membrane; and providing, in the wafer, piezoresistive transduction elements, that are sensitive to strains of the membrane and generate corresponding electrical signals. The step of coupling is carried out by forming the inertial mass on top of a surface of the membrane opposite to the cavity. The accelerometer is advantageously used in a device for monitoring the pressure of a tire of a vehicle.

Abstract: One embodiment of the present invention includes an aircraft instrumentation system for a cockpit instrument panel having a first device associated with a first pilot of an aircraft and positioned on the instrument panel substantially in front of the first pilot. The first device may include a first display and a first controller, which may have a set of controls for controlling the first display and aircraft systems. The instrumentation system may also include a second device associated with a second pilot of the aircraft and positioned on the instrument panel substantially in front of the second pilot. The second device may include a second display and a second controller, which may have a set of controls for controlling the second display and the aircraft systems. The instrumentation may be configured such that at least one of the first display and the second display presents attitude, altitude and airspeed at all times.

Abstract: An improved system and method are disclosed for facilitating target aiming and aircraft control by flight crews using electronic displays. For example, an aircraft display system is disclosed that includes a database for storing target location and boundary data, a processing unit, a position and direction determination unit for use in determining the position of an aiming symbol on a display, a graphics display generator, and a visual display. The processing unit determines whether or not a selected target to be displayed is obscured or covered by the aiming symbol to be displayed. If any portion of the target is obscured or covered by the aiming symbol, then the processing unit directs the graphics display generator to generate graphic control signals for the visual display, which increase the transparency of the portions of the aiming symbol that obscure or cover the target.

Abstract: A vertical deviation indicator and predictor includes a vertical deviation scale having a plurality of vertically spaced markers, one of the markers indicating the vehicle's present vertical position. Current vertical flight path segment symbols are selectively superimposable over the vertical deviation scale in accordance with the vehicle's current vertical flight path segment. Next vertical flight path segment symbols are selectively superimposable over the vertical deviation scale in accordance with the vehicle's next vertical flight path segment, the position thereof being determined by backward extrapolation of the next vertical flight path segment. Thus, the type and position of the current and next vertical flight path segment symbols on the vertical deviation scale provide situational awareness of the present vertical flight path deviation and an indication of an efficient and timely manner for intercepting the desired flight path.

Abstract: A dialog system for dialog between an operator of an aircraft and at least one system of the aircraft including a display configured to display at least one window including a plurality of responsive objects respectively associated with one of multiple functions of the at least one system of the aircraft. Also included is a first cursor control device including a continuous cursor moving mechanism configured to move a cursor in a continuous manner on the display so as to designate a responsive object and a second cursor control device including a discrete cursor moving mechanism configured to move the cursor in a discrete manner on the display responsive object by responsive object so as to designate a responsive object.

Abstract: A dialog method for dialog between an operator of an aircraft and at least one system of the aircraft. The method includes the steps of displaying on a display at least one window including a plurality of responsive objects respectively associated with one of multiple functions of the at least one system of the aircraft, moving a cursor in a continuous manner on the display so as to designate a responsive object, and moving the cursor in a discrete manner on the display, responsive object by responsive object, so as to designate a responsive object.

Abstract: Apparatus and methods for enhancing the accuracy of height above ground measurements in which the registration error between successive images taken of the terrain over which an aircraft is flying is minimized, the earlier image having first been transformed according to measurements of the aircraft linear and angular velocities, the focal length and attitude of the image sensor, and an initial, coarse height estimate. By an iterative process, a more accurate height estimate is obtained.

Abstract: A flight control system includes a primary flight display having a hover display which facilitates operations in DVE conditions. The hover display includes a radar altitude display, heading drift symbology and lateral drift symbology which assists pilots in the detection of drift, which is common in DVE situations and to provide the pilot with a salient cue pertinent to the approach to hover and landing.

Abstract: Methods and systems for presenting images to vehicle occupants are disclosed. A system in accordance with one embodiment of the invention includes at least one display portion configured to display an image and be positioned proximate to a seat location within the vehicle. A first signal receiving portion can be configured to receive an input image signal, and a second signal receiving portion can be configured to receive a motion signal corresponding to a motion of the vehicle. A processing portion can be configured to direct to the at least one display portion a time-varying output signal that appears to move by less than an object actually positioned external to the vehicle would appear to move to an occupant at the seat location of the vehicle. Accordingly, the viewer may be less susceptible to motion sickness by receiving visual cues that correspond to less motion than the occupant feels.

Abstract: A method and apparatus is disclosed for displaying a dynamic parameter of an aircraft, the apparatus comprises a display unit receiving a display signal and displaying a scale that changes dynamically and non-linearly in accordance with a selected display algorithm, the display unit further displaying a pointer pointing to said scale in accordance with a reading of said dynamic parameter, thereby emphasizing a range of said reading of said dynamic parameter.

Abstract: A display system for a vehicle is provided. The display system includes a display configured to render a representation of an intended vehicle path. At least one relative speed indicator is rendered upon the display. The at least one relative speed indicator is configured to move along the representation of the intended vehicle path, in an area of the display that is peripheral to a focus area of the display, in response to a difference between an actual value of a speed-based parameter and a preferred value of a speed-based parameter of the vehicle.

Abstract: A flight information display for the flight deck of an aircraft showing a pictorial side view of the flight path or the area directly in front of the aircraft area having a selected distance of at least 0.5 nautical miles, comprising (a) a pictorial representation to scale of the profile of the highest elevations of a swath of terrain along said path or area, (b) an icon positioned on the left or right side of the display representing the aircraft, the altitude of which is to scale with the height of the terrain, and (c) an altitude reference scale; wherein the width of the swath is at least 0.1 nautical miles and no greater than the distance of the minimum accuracy of the means for determining the aircraft's location.

Abstract: The present invention provides a solid-state rotational rate sensor device formed by a thin-film for generating an electrical voltage output proportional to the rate of rotational motion. The precision thin-film piezoelectric elements are configured and arranged on a semi-rigid structure to detect rotation (such as pitch, roll, and yaw) while rejecting spurious noise created by vibration, thermal gradients, and electro-magnetic interference.

Abstract: Methods and systems for presenting images to vehicle occupants are disclosed. A system in accordance with one embodiment of the invention includes at least one display portion configured to display an image and be positioned proximate to a seat location within the vehicle. A first signal receiving portion can be configured to receive an input image signal, and a second signal receiving portion can be configured to receive a motion signal corresponding to a motion of the vehicle. A processing portion can be configured to direct to the at least one display portion a time-varying output signal that appears to move by less than an object actually positioned external to the vehicle would appear to move to an occupant at the seat location of the vehicle. Accordingly, the viewer may be less susceptible to motion sickness by receiving visual cues that correspond to less motion than the occupant feels.

Abstract: A compact, lightweight, cost effective, self-contained standby electronic navigation system with high signal-to-noise ratio and good dynamic stability is provided. The system includes a first sensor module for providing a plurality of rotational rate signals, a second sensor module for providing a plurality of compensation signals, and a microcontroller module for processing the rotational rate signals and the compensation signals and sending the signals to a display for displaying attitude information, directional information, and turn coordinate information on a single screen simultaneously. In one embodiment, the first sensor module includes a plurality of rotational sensors made of piezoelectric elements. The piezoelectric elements are made from a single sheet of piezoelectric material so that the elements possess uniform characteristics, and are arranged to reduce systematic drift and random noise normally present in a rotational rate sensor. The sensors can be configured on a single multi-sensor chip.

Abstract: The invention relates to a method device for displaying, in a way that is easy for an operator, such as a pilot in an aircraft, to grasp and understand, the direction to objects (A, B) in the surrounding space. In accordance with the invention the object is projected onto a projection surface (3) comprised of the envelope surface of a conical solid of revolution, where the operator is somewhere vertically (h) on the axis of rotation (2) about which the envelope surface (3) is created. Thereafter, the operator observes, on a display surface (I) such as a viewing screen, a plan view from above of the conical envelope surface, where the horizontal direction (c, d) to the objects, and each object's height (a, b) compared to one's own height (h), represented by a circular curve (6), are easily read.

Abstract: The pilot's awareness of the aircraft's state is enhanced by supplementing the flight modes area (FMA) in the upper region of the primary flight display (PFD) with additional annunciators. The FMA in the present invention displays, in the active lateral modes region, the name of the waypoint the aircraft is flying towards and, if the waypoint is part of a published procedure, the procedure name is displayed in this area. Moreover, if the controls of the aircraft are set for a specific target, then the target, along with the mode annunciators, are displayed in the active vertical modes region of the FMA. Furthermore, if the aircraft starts to deviate from the preselected altitude, the pilot is alerted of the uncoordinated condition by a CHECK ASEL annunciation which is displayed in the lower center region of the FMA, namely below the autopilot (AP) annunciator.

Abstract: A primary flight display with three-dimensional capability provides information in an intuitive format for enhanced situational awareness. The display also includes other navigational data such as airspeed, attitude, altitude, and heading. The display may also include three view slices, a pictorial autopilot status indicator, vertical and lateral deviation and deviation history, glide slope and localizer information, airport and runway information, past position history of the aircraft and other nearby aircraft. The display may depict potential threats to the aircraft such as terrain or other manmade obstacles, nearby aircraft, severe weather thus increasing situational awareness with respect thereto. In a preferred embodiment, the three dimensional tactical map is implemented as a frequency separated display.

Abstract: To provide a small portable, (not permanently fixed or mounted in panel of Aircraft) dual power source, independent aircraft attitude indicator, to be used as a back up to the main vacuum driven indicator in light to medium general aviation aircraft. The purpose would be to facilitate control or navigation of the aircraft in case of a vacuum pump failure to the main indicator. The unit size would be approximately 3 by 5 inches and would be composed of the following.

Abstract: A standby instrument, such as a standby attitude indicator, including a display, an attitude sensor module, and a speech synthesizer connected to the attitude sensor module. The standby instrument is controllable to cause the speech synthesizer to audibly speak attitude information generated by the attitude sensor module, thereby providing attitude information to a pilot even when a view of the standby instrument is impaired by, e.g., smoke.

Abstract: A compact, lightweight, cost effective, self-contained standby electronic navigation system with high signal-to-noise ratio and good dynamic stability is provided. The system includes a first sensor module for providing a plurality of rotational rate signals, a second sensor module for providing a plurality of compensation signals, and a microcontroller module for processing the rotational rate signals and the compensation signals and sending the signals to a display for displaying attitude information, directional information, and turn coordinate information on a single screen simultaneously. In one embodiment, the first sensor module includes a plurality of rotational sensors made of piezoelectric elements. The piezoelectric elements are made from a single sheet of piezoelectric material so that the elements possess uniform characteristics, and are arranged to reduce systematic drift and random noise normally present in a rotational rate sensor. The sensors can be configured on a single multi-sensor chip.

Abstract: A navigation performance based flight path deviation display assembly includes a display and a display processor capable of generating an image upon the display. The image includes at least one flight path scale comprising a reference point bounded by end markers extending in at least one of a lateral and vertical direction. The display also includes at least one moveable deviation pointer disposed on the flight path scales. Additionally, the image includes a representation of at least one extendable navigation error disposed on the flight path scale, and extending from at least one of the end markers toward the reference point based upon an actual navigation performance (ANP) and the RNP for the aircraft. The image may also include at least one moveable intersecting flight path pointer disposed on the flight path scales.

Abstract: An aircraft head up display system that displays a basic mode, an en route mode, or an approach/landing mode. When the aircraft attitude changes to predefined unusual attitude conditions, the display changes to an unusual attitude mode to indicate the unusual attitude condition. The display in the unusual attitude mode removes non-essential symbols and displays the aircraft air speed, altitude and attitude. The attitude display includes an unusual attitude ball display containing a horizon symbol, a series of simulated section lines to indicate an area below the horizon, a pitch ladder, a water line indicator, and a roll indicator.

Abstract: The present invention provides methods of and apparatus for determining the inertial attitude of an aerospace vehicle. In one embodiment, the invention provides a rotational astronomical object-sighting concept to determine the inertial attitude of an axis of the aerospace vehicle without the star identification or dragback. In another embodiment, the invention provides an attitude measurement apparatus comprising a high sensitivity optical sensor and a low power inertial sensor.

Abstract: The present invention provides an alternative means of displaying aircraft flight information traditionally provided by a standalone rate of turn indicator on the aircraft instrumentation panel. The bank angle effective to achieve a rate of turn equal to a desired rate of turn for an aircraft is displayed to the pilot by generating and displaying one or more bank angle markers on the roll scale of an aircraft attitude indicator. The position of the desired rate of turn bank angle markers may be updated continuously as a function of airspeed and other flight parameters. The present invention enables a pilot to perform a coordinated turn at a desired rate of turn without having to reference a separate rate of turn indicator on the instrumentation panel and/or without having to independently calculate the associated bank angle according to any known “rule of thumb” or other estimation method.

Abstract: A human centered informational display is disclosed that can be used with vehicles (e.g. aircraft) and in other operational environments where rapid human centered comprehension of an operational environment is required. The informational display integrates all cockpit information into a single display in such a way that the pilot can clearly understand with a glance, his or her spatial orientation, flight performance, engine status and power management issues, radio aids, and the location of other air traffic, runways, weather, and terrain features. With OZ the information is presented as an integrated whole, the pilot instantaneously recognizes flight path deviations, and is instinctively drawn to the corrective maneuvers. Our laboratory studies indicate that OZ transfers to the pilot all of the integrated display information in less than 200 milliseconds. The reacquisition of scan can be accomplished just as quickly. Thus, the time constants for forming a mental model are near instantaneous.

Abstract: Terrain navigation apparatus (1) for a stationary or moving vehicle (2) when the apparatus (1) is mounted thereon, including a system (3) for determining position, velocity, altitude and attitude incorporating at least six sensing means operable to provide signals indicative of a first measured height (5), a first velocity (7) and a first position (9) of the vehicle (2), scanning means (11) operable to scan terrain (13) around the vehicle (2) and measure a range (15) from the vehicle (2) thereto, first combining means (17) for combining signals indicative of the first measured height, the range and the first position (5, 15, 9) of the vehicle (2), together with error estimates (19) associated therewith, and for outputting results of said combining process, error-estimating means (21) for receiving as input signals results of said combining process and for providing said error estimates(19), such that the error-estimating means (21) and first combining means (17) operatively interact to effect terrain navigati

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: A process and system are disclosed for representing flight guiding information for an aircraft. A spatial representation of the air space with at least one horizon and the previously calculated flight path of the aircraft is represented by means of video equipment. The representation of the previously calculated flight path includes the previously calculated position and previously calculated attitude of the aircraft at different moments in time. The previously calculated flight path is represented by at least two bodies which extend along the flight path and of which at least one is represented to the left of the flight path and at least one is represented to the right of the flight path.

Abstract: A system and method of estimating the attitude of a spacecraft is disclosed. A three-axis inertial-based estimate of spacecraft attitude is produced and is compared to a stellar-based estimate of spacecraft attitude. A Kalman filter having states associated with gyro scale factor and/or misalignment errors compares the stellar-based attitude estimate to the inertial-based estimate of attitude and apportions the total error into three time varying matrices. A first time varying matrix is associated with gyro scale factor and misalignment errors, a second time varying matrix is associated with gyro bias errors, and a third time varying matrix is associated with attitude errors. The time varying matrices are applied as corrective feedbacks to the inertial-based estimate of spacecraft attitude and are adaptively adjusted to minimize the error therein.

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: A combined altitude and height-above-ground indicator for an aircraft includes a first sensor and a second sensor which respectively sense altitude and height-above-ground, a processor for processing the information supplied by the first and second sensors, and a display for displaying the altitude and height-above-ground information, showing the two items of information against each other, on the same scale against at least one pointer.

Abstract: The invention relates to systems for aiding the piloting of aircraft, mainly for take-off and landing under poor conditions of visibility.In order to benefit from the contribution of head-up displays, which exhibit symbols for the artificial horizon line, aircraft longitudinal attitude and ground speed vector, without using an IRS inertial unit to supply the heading and attitude information, it is proposed to use a non-inertial AHRS unit associated with a compass, and periodically to correct the information which it supplies, in order to exhibit the attitude symbols with the aid of the corrected information rather than the raw information from the AHRS unit. The correction is given by two GPS receivers (GPS1, GPS2) associated with antennas (A1, A2) on the top of the aircraft, an interferometric measurement of radiofrequency carrier phase being made to determine a direction vector of the aircraft.

Abstract: The present invention is directed to a non-normalized aircraft angle-of-attack indicating system. An angle-of-attack vane produces a signal .alpha.' indicative of raw aircraft angle-of-attack. A pitot-static system (68) produces output signals representative of aircraft static pressure and total pressure, P.sub.s and P.sub.t, respectively. The signals .alpha.', P.sub.s and P.sub.t are fed to an air data computer (66) which correspondingly produces an aircraft actual angle-of-attack value .alpha. and a calculated Mach number, M. Configuration sensors (80) produce output signals representative of gear position, g, flap position, f, and speed brake position, sb. The signals .alpha., M, g, f and sb are fed to a display computer (76). The display computer includes a submodule (90) which utilizes a lookup table to determine a value of angle-of-attack stick shaker, .alpha..sub.ss from the values of M, g, f and sb. A second submodule (92) utilizes a lookup table to produce a second angle-of-attack reference value .