Abstract: An aircraft avionics system and method for automatically determining an aircraft position. The system and method determine distances to UAT or SSR ground stations. The system and method then determine the position of an aircraft by determining true bearings to SSR or UAT ground stations and determining the possible positions for the aircraft at which the aircraft is at respective bearings to each SSR or UAT ground station. An alternative system and method may determine distances based on timing signals in transmissions from the ground stations and determine one or more possible positions for the aircraft at which the aircraft is at the determined distances from respective ground stations. The system and method also may use dead reckoning or VOR or ADF signals to reduce the possible positions for the aircraft to a single possible position.

Abstract: An aircraft traffic alert system that minimizes false alarms and unnecessary alerts by automatically adjusting the sensitivity of the system based on proximity to an airport. The system also can use information from a flight management system (FMS) or GPS navigation system (GNS) to only adjust the sensitivity near a destination airport and to suppress potential alerts for possible collisions with other aircraft that will be moot based on planned course changes of the subject aircraft. The system also can suppress alerts related to another aircraft when the other aircraft is landing on a parallel runway to the runway on which the subject aircraft is landing. The system may use multiple sensitivity levels based on different airspace classes, each class being associated with a different sensitivity level.

Abstract: An aircraft avionics system and method for automatically determining an aircraft position. The system and method determine distances to UAT ground stations based on timing signals in transmissions from the UAT ground stations and determines one or more possible positions for the aircraft at which the aircraft is at the determined distances from respective UAT ground stations. The system and method may use three or more UAT ground stations to reduce the possible positions for the aircraft to a single possible position. The system and method also may use dead reckoning or VOR or ADF signals to reduce the possible positions for the aircraft to a single possible position. The system and method may also determine the position of an aircraft by determining true bearings to SSR ground stations and determining the possible positions for the aircraft at which the aircraft is at respective bearings to each SSR ground station.

Abstract: An aircraft traffic alert system that minimizes false alarms and unnecessary alerts by automatically adjusting the sensitivity of the system based on proximity to an airport. The system also can use information from a flight management system (FMS) or GPS navigation system (GNS) to only adjust the sensitivity near a destination airport and to suppress potential alerts for possible collisions with other aircraft that will be moot based on planned course changes of the subject aircraft. The system also can suppress alerts related to another aircraft when the other aircraft is landing on a parallel runway to the runway on which the subject aircraft is landing. The system may use multiple sensitivity levels based on different airspace classes, each class being associated with a different sensitivity level.

Abstract: A lightning detector designed for aircraft carried applications provides for improved lightning discrimination and display. The instrument employs a relatively wide band receiver so as to retain the received waveform or digital replicas thereof. This allows more precise discrimination between desired lightning signals and noise. Signals are processed to provide for effective display of the available information. The display modes that are enabled by the signals include flash and cell mode as well as a combined flash and cell mode. The cell mode provides for generating and displaying a cumulative weight of lightning activity, giving each strike a regional effect as opposed to illustrating it as a point. Color is used to improve the user's grasp of the displayed information; the color illustrating increased intensity from the blue-green to the yellow-red. Flash mode shows locations of the different flashes within the range scale; this mode too may use color for a similar effect.

Abstract: A lightning strike to an aircraft causes problems in existing aircraft equipment. To offset the problem, weather equipment can be used, but the weather equipment is prone to noise interference with existing aircraft equipment. By effectively positioning the weather equipment, the present invention solves the noise interference problem. In particular, the process detects an environment event, using weather equipment, on the subject aircraft. Next, the system identifies an origination point of noise, resulting from the detected environment event, in internal aircraft equipment. After identifying the origination point of the noise, the system makes a measurement to determine if the noise is interfering with a signal of the internal aircraft equipment. If interference exists, an operator cancels the noise and adjusts the location of the weather equipment in an external surface of the subject aircraft in such a manner as to provide an interference free environment for the internal aircraft equipment.

Abstract: The present invention relates to a system and method for detecting lightning activity. When a lightning strike is close enough to a receiver, the strength of the signal received will cause the receiver to saturate. In such a situation, a non-filtered signal is used to calculate a range and bearing. In one specific embodiment, a receiver detects energy emitted by a lightning strike and separates the lightning strike to a filtered signal and non-filtered signal. A saturation detector determines if the filtered signal is saturated prior to the filtered signal being filtered. In response to the filtered signal being saturated, a processor processes the non-filtered signal from the receiver, estimates locations of the detected lightning strike relative to the system, determines a cumulative effect of the lightning strike spaced in distance and time, and generates display signals to illustrate the cumulative effect with respect to a grid.

Abstract: A critical point on a runway indicates a point at which an aircraft may experience a runway overrun if landing beyond the critical point. A path projection is extended from the aircraft at a descent slope angle to determine whether the aircraft will land beyond the critical point at the current descent slope. Timely alerts may be provided by accounting for the time required to announce a distance value, and the distance traveled during the announcement.

Abstract: A critical point on a runway indicates a point at which an aircraft may experience a runway overrun if landing beyond the critical point. A path projection is extended from the aircraft at a descent slope angle to determine whether the aircraft will land beyond the critical point at the current descent slope. Timely alerts may be provided by accounting for the time required to announce a distance value, and the distance traveled during the announcement.

Abstract: A critical point on a runway indicates a point at which an aircraft may experience a runway overrun if landing beyond the critical point. A path projection is extended from the aircraft at a descent slope angle to determine whether the aircraft will land beyond the critical point at the current descent slope. Timely alerts may be provided by accounting for the time required to announce a distance value, and the distance traveled during the announcement.

Abstract: The location of weather activity from a moving platform such as an aircraft is enhanced using triangulation in time. More particularly, a first measurement of the weather activity is made relative to the aircraft at a first time. A second measurement of the location of the weather activity is made from the aircraft at a second period in time. The first measurement is modified or updated to correct for the change in position of the aircraft between the first and second measurements and then the modified data is compared with the data of the second measurement to enhance the location of the weather activity.

Abstract: Two pairs of signals determinative of bearing to a transmitter are developed from two pairs of directional antennas. The signals, converted to digital form, are compared to each other to develop a result signal. The result signal is used to select a primary pair out of the original two pair of signals. The non-primary pair of signals are compared to each other to develop a binary sign bit. The primary signal pair, the result signal and the sign signal are applied to a table to develop a bearing quantity related to the bearing to the transmitter.

Abstract: A globally-addressable array of electronic circuit elements having distributed intelligence. Each circuit element location is connected to a common bus structure which can address each circuit element and transfer data to and from each element. Logic circuitry at each circuit element location recognizes data addressed to a respective circuit element location, and converts data received into an operating level for a respective transducer element. Data transfer to each element location can be made using conventional compression techniques. The data transfer can be bidirectional so that a sensed condition may be transferred from the location over the common bus structure.

Abstract: An antenna arrangement on a host aircraft for generating power signals related to a direction from which a transponder reply signal is received from a threat aircraft. The arrangement includes first and second monopole antenna elements arranged along a first axis of the host aircraft, third and fourth monopole antenna elements arranged along a second axis of the host aircraft, with the second axis being orthogonal to the first axis, a first quadrature combiner coupled to the first and second monopole antenna elements for generating first and second signals from the received reply signal, and a second quadrature combiner coupled to the third and fourth monopole antenna elements for generating third and fourth signals from the received reply signal. The respective power levels of the first, second, third and fourth signals are related to the direction from which the reply signal is received from the threat aircraft.

Abstract: A proximity warning device for aircraft responds solely to transmissions from transponders. The host aircraft has a host transponder and a signal is generated therein and coupled to the device to indicate transmission of a host reply. Selective suppression is implemented based on presence of an SSR beam which is indicated by the signal. Suppression pulses have a fixed duration but randomly selected intervening durations. Data collection proceeds without regard for suppression or the presence of host replies. The shaping of data collection intervals free of interference from suppression provides for improved efficiency for later data decoding and processing. The signal is used to specially mark collected data generated by a host reply. The ability to discriminate between host and other replies allows completely new performance monitoring functions. In one case, the health of the receiver is deduced from the amplitude of host replies.

Abstract: A passive aircraft Traffic alert and Collision Avoidance Device (TCAD) is based on sensing and responding to transponder replies of other aircraft to SSR interrogations. In order to avoid masking other aircraft replies by the host transponder TCAD repeatedly and randomly suppresses the host transponder and simultaneoulsly listens for other aircraft replies. Suppression on each occasion is effective for an equal and predetermined duration which is much longer than a typical replay, in a preferred embodiment the suppression/listen duration is 725 .mu.s. In this embodiment the time between successive suppression/listen occasions is random between 725 .mu.s. and 5.025 ms. with an average value of about 2.9 ms. Digital signal processing is used to detect and discard garbled or overlapping replies. Each valid reply, exhibiting a minimum pulse amplitude, is decoded and correlated with a calibrated range parameter and given a time tag.

Abstract: A passive aircraft Traffic alert and Collision Avoidance device (TCAD) is based on sensing and responding to transponder replies of other aircraft to SSR interrogations. In order to avoid masking other aircraft replies by the host transponder TCAD repeatedly and randomly suppresses the host transponder and simultaneously listens for other aircraft replies. Suppression on each occasion is effective for an equal and predetermined duration which is much longer than a typical reply, in a preferred embodiment the suppression/listen duration is 725 .mu.s. In this embodiment the time between successive suppression/listen occasions is random between 725 .mu.s. and 5.025 ms. with an average value of about 2.9 ms. Digital signal processing is used to detect and discard garbled or overlapping replies. Each valid reply, exhibiting a minimum pulse amplitude, is decoded and correlated with a calibrated range parameter and given a time tag.