Abstract: Systems and methods communicate weather information between aircraft using low bandwidth communication transceivers. An exemplary embodiment receives weather information from a weather radar system on board a remote aircraft, processes the received weather information into weather radar image information that is displayable on at least a display, processes the weather radar image information into a reduced size dataset, and communicates the reduced size dataset to an installation aircraft over the low bandwidth communication channel, wherein the low bandwidth communication channel is generated by a low bandwidth communication transceiver on board the remote aircraft.

Abstract: Systems and methods distinguish weather radar returns from terrain radar returns. An exemplary embodiment receives a radar return from a weather radar system on board an installation vehicle, receives ground-based weather radar information, compares a location of the radar return received from the onboard weather radar system with a corresponding location in the received ground-based, and determines that the radar return received from the onboard weather radar system is a weather radar return when a location in the received ground-based weather radar information indicates a presence of weather at the location of the radar return.

Abstract: Systems and methods communicate weather information between aircraft using low bandwidth communication transceivers. An exemplary embodiment receives weather information from a weather radar system on board a remote aircraft, processes the received weather information into weather radar image information that is displayable on at least a display, processes the weather radar image information into a reduced size dataset, and communicates the reduced size dataset to an installation aircraft over the low bandwidth communication channel, wherein the low bandwidth communication channel is generated by a low bandwidth communication transceiver on board the remote aircraft.

Abstract: Systems and methods distinguish weather radar returns from terrain radar returns. An exemplary embodiment receives a radar return from a weather radar system on board an installation vehicle, receives ground-based weather radar information, compares a location of the radar return received from the onboard weather radar system with a corresponding location in the received ground-based, and determines that the radar return received from the onboard weather radar system is a weather radar return when a location in the received ground-based weather radar information indicates a presence of weather at the location of the radar return.

Abstract: Systems and methods for presenting information pertaining to a weather object on a display. A process includes displaying on the aircraft display terrain information, weather reflectivity information, and at least one hazardous weather icon corresponding to the weather, wherein the hazardous weather icon indicates a determined hazard level associated with the weather; receiving a selection to display only the hazardous weather icon; and in response to receiving the selection, continuing display of the hazardous weather icon and suppressing display of the terrain information and the weather reflectivity information.

Abstract: Warning systems for aircraft that provide a warning to the pilot of an excessive altitude loss or an excessive descent rate after take-off as long as he is flying below a predetermined altitude have the problem that they require a valid radio altitude signal for proper operation, and tend to generate nuisance warnings when used in low flying aircraft. This problem is solved by comparing the accumulated altitude loss after take-off (12, 14, 62, 34) with the product of a barometrically derived altitude and the length of time the aircraft has been flying (12, 14, 30, 32, 34). A warning is generated if the altitude loss is excessive for the accumulated time-altitude product after take-off (38, 40). Thus, the system is more sensitive immediately after take-off and becomes less sensitive as flight time is accumulated to permit low level maneuvering without generating false or nuisance warnings, and does not require a valid radio altitude signal to generate a warning.

Abstract: Warning systems that monitor the altitude above ground and descent rate of an aircraft and generates a warning if the descent rate of the aircraft is excessive for the altitude in which the aircraft is flying are well suited to aircraft whose flight and operational characteristics are readily predictable but not as suitable for aircraft, such as tactical aircraft whose operating conditions are not so predictable. To overcome this problem, the criteria for providing the warnings are altered (30, 32) as a function of flight configuration (16, 18) to optimize the warnings for different flight conditions.

Abstract: Warning systems that monitor the altitude above ground and descent rate of an aircraft and generate a warning if the descent rate of the aircraft is excessive for the altitude in which the aircraft is flying are well suited to aircraft whose flight and operational characteristics are readily predictable but not as suitable for aircraft, such as tactical aircraft whose operating conditions are not so predictable. To overcome this problem, the criteria for providing the warnings are altered (30, 32) as a function of flight configuration (16, 18) to optimize the warnings for different flight conditions.

Abstract: A proximity to terrain warning system for aircraft utilizes a first set of warning criteria to generate a warning in the event of insufficient terrain clearance after take off. A different set of criteria are employed to generate warnings when the aircraft in in a cruise or approach phase of flight or on a tactical mission. Mode switching is provided to select the appropriate criteria and to select an excessive descent after take-off set of warning criteria in addition to the first set of criteria when appropriate.

Abstract: A ground proximity warning system is disclosed which can recognize when an aircraft is on a final approach to an airport without utilizing a landing flap signal input. Airports together with the surrounding terrain topography are modeled by a simple geometric shape, such as, an inverted truncated cone, and stored on-board the aircraft. The system uses navigational data to determine the distance of the aircraft from the geometric model. Once the aircraft is determined to be within the area defined by the geometric model, the system provides an enabling envelope indicative that the aircraft is on a final approach for enabling various ground proximity warning systems. Also disclosed is a system for altering the enabling envelope as a function of the aircraft's alignment with a particular runway.

Abstract: A ground proximity warning system especially adapted for a tactical aircraft provides the pilot with a warning in the event that the closure rate is excessive for the altitude above ground at which the aircraft is flying. The descent rate of the aircraft is monitored and used to bias the closure rate warning signal to reduce nuisance warnings when the excessive closure rate is part of an intentional maneuver such as a dive during a tactical mission.

Abstract: A terrain advisory system utilizes stored data representative of terrain and other obstacles in predetermined geographical areas of interest to provide advisory warnings of the proximity of terrain, obstacles and restricted areas as they are approached. When used in a vehicle such as an aircraft, the system monitors the position, altitude, ground speed, ground track and the vertical speed of the vehicle and provides advisory indications of the position and path of travel of the vehicle with respect to obstacles and terrain. Such advisory indications may take the form of voice warnings describing the nature and position of any obstacles, or a visual display showing the position of the obstacles and terrain with respect to the vehicle.

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: To increase the effectivity of warnings and to decrease nuisance warnings in a ground proximity warning system having several modes of operation, the switching from one mode to another is done as a function of radio altitude and time. In addition, in a ground proximity warning system where a warning signal is generated in accordance with a predetermined relationship between flight parameters, one or more of these parameters can be varied as a function of radio altitude and time in order to, for example, increase the altitude above ground as a function of radio altitude and time from take-off that a terrain clearance warning is generated or to decrease as a function of radio altitude and time, the radio altitude below which a negative climb after take-off warning is generated.