Abstract: An apparatus, method and computer program product for suppressing an alert generated by a terrain awareness system rotary wing aircraft of potentially hazardous proximity to terrain also reduces nuisance warnings and provides a terrain display consistent with the unique performance capabilities of such aircraft.

Abstract: The present invention provides apparatus, methods, and computer program products that monitor the altitude of an aircraft with respect to a selected runway. If the altitude of the aircraft is below a minimum glideslope with respect to the selected runway, the apparatus, methods, and computer program products of the present invention alert the flight crew, such that the altitude of the aircraft can be increased. This, in turn, increases time for reaction to abrupt changes in elevation near the selected runway. Specifically, the apparatus, methods, and computer program products of the present invention define a runway field clearance floor envelope about the selected runway that represents different preselected altitudes above the selected runway at respective distances from the selected runway. The apparatus, method, and computer program products of the present invention compare the altitude of the aircraft with respect to the selected runway to the runway field clearance floor envelope.

Abstract: A bow sight provides horizontal, vertical and at least one rotational adjustment mechanism which provides continuous movement of the sight ring without having to release a locking mechanism and still not allow unintentional movement of the sight ring. The sight has a plurality of sight pins having illuminated tips located at spaced-apart locations along a vertical sight line which extends across the sight ring. First adjustment mechanisms allow the sight pins to be rotated in order to set the location of the tips along the sight line and second adjustment mechanisms allow the sight pins to be moved along their longitudinal axes to align them with the sight line after they have been rotated. The sight also includes particular horizontal and vertical micro adjustment mechanisms which allow very small movements of the sight ring in the horizontal and vertical directions without having to release a locking mechanism.

Abstract: The present invention provides several apparatus, methods, and computer program products for determining a look ahead distance value for use in a ground proximity warning system. Specifically, the present invention provides apparatus, methods, and computer program products that generate a candidate look ahead distance value that provides a constant reaction time for varying aircraft speeds. The apparatus of the present invention includes a processor that generates the constant reaction time look ahead distance by multiplying a desired reaction time by the speed of the aircraft. This constant reaction time look ahead distance value is compared by the processor to other candidate look ahead distance values that have variable reaction times for varying aircraft speeds. If the aircraft is traveling at a relatively high speed, the processor of the present invention selects the constant reaction time look ahead distance value for use in the ground proximity warning system.

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: 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: An aircraft terrain warning generator is provided having a terrain and obstacle warning envelope having a lower boundary formed according to the lesser of the current aircraft flight path angle and the obtainable climb gradient.

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: An aircraft terrain warning generator is provided having a terrain and obstacle warning envelope having a lower boundary formed according to the lesser of the current aircraft flight path angle and the obtainable climb gradient.

Abstract: A method, apparatus and computer program product for assisting the pilot of an aircraft in making a go-around decision. Various aircraft parameters are monitored during the approach to land and a risk level assessed. When the risk level exceeds a specified threshold, an alert is provided.

Abstract: An apparatus, system, method and computer program product to verify proper operation of an aircraft altimetry system. Aural and visual alerts may optionally be provided when a fault in the altimetry is detected.

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 terrain awareness system (TAS) provides LOOK-AHEAD/LOOK-DOWN as well as LOOK-UP terrain advisory and warning indications to the pilot of an aircraft of a hazardous flight condition. The TAS includes an airport data base as well as a terrain data base that is structured to provide various resolutions depending on the topography of the particular geographic area of interest. Navigational data from a satellite-based navigational system, such as a global positioning system (GPS), is used to provide a LOOK-AHEAD/LOOK-DOWN and LOOK-UP terrain advisory and terrain warning indications based upon the current position and projected flight path of the aircraft. Since the terrain advisory and the warning signals are a function of the flight path of the aircraft, nuisance warnings are minimized.

Abstract: Methods and apparatus for determining altitude, specifically altitude in an aircraft, and an estimated error of the altitude. The altitude determination preferably uses a first altitude based on hydrostatic calculations, including local pressure and temperature, as well as a second altitude which is preferably a GPS altitude. A radio altimetry can also be used instead of or to complement the GPS altitude. Other sources of altitude determination can be used in the equation for the calculation of the final altitude. Each of the sources of altitude determination is provided with a complementary estimated error. In the final determination of the probable altitude, each source of altitude information is preferably accorded a weighting according to the estimated error of the altitude source. For global positioning altitude, the final combination of the altitude sources uses a complementary filter which takes into account the selective availability of the GPS altitude.

Abstract: A terrain awareness system (TAS) provides LOOK-AHEAD/LOOK-DOWN as well as LOOK-UP terrain advisory and warning indications to the pilot of an aircraft of a hazardous flight condition. The TAS includes an airport data base as well as a terrain data base that is structured to provide various resolutions depending on the topography of the particular geographic area of interest. Navigational data from a satellite-based navigational system, such as a global positioning system (GPS), is used to provide a LOOK-AHEAD/LOOK-DOWN and LOOK-UP terrain advisory and terrain warning indications based upon the current position and projected flight path of the aircraft. Since the terrain advisory and the warning signals are a function of the flight path of the aircraft, nuisance warnings are minimized.

Abstract: A terrain-awareness system (TAS) provides LOOK-AHEAD/LOOK-DOWN as well as LOOK-UP terrain advisory and warning indications to the pilot of an aircraft of a hazardous flight condition. The TAS includes an airport data base as well as a terrain data base that is structured to provide various resolutions depending on the topography of the particular geographic area of interest. Navigational data from a satellite-based navigational system, such as a global positioning system (GPS), is used to provide a LOOK-AHEAD/LOOK-DOWN and LOOK-UP terrain advisory and terrain warning indications based upon the current position and projected flight path of the aircraft. Since the terrain advisory and the warning signals are a function of the flight path of the aircraft, nuisance warnings are minimized.

Abstract: A terrain awareness system (TAS) provides LOOK-AHEAD/LOOK-DOWN as well as LOOK-UP terrain advisory and warning indications to the pilot of an aircraft of a hazardous flight condition. The TAS includes an airport data base as well as a terrain data base that is structured to provide various resolutions depending on the topography of the particular geographic area of interest. Navigational data from a satellite-based navigational system, such as a global positioning system (GPS), is used to provide a LOOK-AHEAD/LOOK-DOWN and LOOK-UP terrain advisory and terrain warning indications based upon the current position and projected flight path of the aircraft. Since the terrain advisory and the warning signals are a function of the flight path of the aircraft, nuisance warnings are minimized.

Abstract: A cable adjuster for individually adjusting the cable ends of a split cable on a compound archery bow has a body with a medial slot located in it which fits over the end of the pin which journal the bow cams. The slot is configured so that the body can rotate on the pin and be slid toward and away from the center of the bow. A retainer secures the body rotatably on the pin. A button attached to the body releasably engages a loop located at the cable ends. A notch is located between the body and the button to seat the cable loop on the device. The button and notch are angled with respect to the body such that when a force which is applied to the cable, the elongate axis of the body remains normal to the axis of the pin so that the body can rotate on the pin without binding. A set screw extends through the top end of the body into the slot where it contacts the top of the pin when force is applied to the cable.

Abstract: The improved cable guard for a compound archery bow includes an elongated, flexible resilient rod having a rear portion and an opposite front portion, the flexibility of the rod increasing from the front portion to the rear portion. Preferably, the front portion of the rod is generally circular in transverse cross-section while the rear portion of the rod is semi-circular in such cross-section, with a flat side facing away from the bow cables and toward the bowstring. In another embodiment both the front and rear portions of the rod are generally circular in cross-section, but the diameter of the rod decreases from the front portion to the rear portion thereof. The cable guard also includes an elongated transversely extending bracket the medial end of which is adapted to be secured to the rear end of the bow riser while the distal end of the bracket extends laterally of the riser and releasably secures the rod so that its position relative to the bow riser can be adjusted.

Abstract: A width-adjustable step tread has first and second members, each extending along at least an appendage of a width of the step tread. Each of the first and second members have identical cross-sectional shapes as defined by a web with two opposing edges. A first appendage extends along one edge of the web defining an exterior surface and a second appendage extends along the other edge of the web defining an interior surface. The interior surface of the second appendage forms a female part which receives a male part formed by the exterior surface of the first appendage so that the first appendage of each member couples in sliding engagement with the second appendage of the other member.