Abstract: Systems and methods for providing aircraft heading information are provided. In one embodiment, an attitude heading reference device comprises: at least one interface for receiving heading information from one or more IRUs; at least one set of gyroscopes and accelerometers; a memory device for storing data representing heading information received via the at least one interface; and a heading calculator coupled to the at least one interface, the at least one set of gyroscopes and accelerometers, and the memory device. The heading calculator generating a heading output signal based on heading information when reliable heading information is received over the at least one interface; the heading calculator generating the heading output signal based on data from the memory device regarding previously reliable heading information and an output of the at least one set of gyroscopes and accelerometers when reliable heading information is not received over the at least one interface.

Abstract: Systems and methods for providing aircraft heading information are provided. In one embodiment, an attitude heading reference device comprises: at least one interface for receiving heading information from one or more IRUs; at least one set of gyroscopes and accelerometers; a memory device for storing data representing heading information received via the at least one interface; and a heading calculator coupled to the at least one interface, the at least one set of gyroscopes and accelerometers, and the memory device. The heading calculator generating a heading output signal based on heading information when reliable heading information is received over the at least one interface; the heading calculator generating the heading output signal based on data from the memory device regarding previously reliable heading information and an output of the at least one set of gyroscopes and accelerometers when reliable heading information is not received over the at least one interface.

Abstract: Systems and methods for providing aircraft heading information are provided. In one embodiment, an attitude heading reference device comprises: at least one interface for receiving heading information from one or more IRUs; at least one set of gyroscopes and accelerometers; a memory device for storing data representing heading information received via the at least one interface; and a heading calculator coupled to the at least one interface, the at least one set of gyroscopes and accelerometers, and the memory device. The heading calculator generating a heading output signal based on heading information when reliable heading information is received over the at least one interface; the heading calculator generating the heading output signal based on data from the memory device regarding previously reliable heading information and an output of the at least one set of gyroscopes and accelerometers when reliable heading information is not received over the at least one interface.

Abstract: An aircraft inertial system comprises at least two inertial reference units (IRU) that provide a first set of inertial signal data for an aircraft and at least two attitude heading reference systems (AHRS) that provide a second set of the inertial signal data for the aircraft. At least one primary flight display receives the first and the second sets of the inertial signal data, and a standby flight display receives at least the second set of the inertial signal data from at least one of the AHRS. When a single fault condition occurs, the primary flight display continues to operate with fail-operational redundancy from at least three independent sources of the inertial signal data comprising one or more IRU and AHRS combinations. The standby flight display will operate using a different source of the inertial signal data than the source of the inertial signal data for the primary flight display.

Abstract: Systems and methods for providing aircraft heading information are provided. In one embodiment, an attitude heading reference device comprises: at least one interface for receiving heading information from one or more IRUs; at least one set of gyroscopes and accelerometers; a memory device for storing data representing heading information received via the at least one interface; and a heading calculator coupled to the at least one interface, the at least one set of gyroscopes and accelerometers, and the memory device. The heading calculator generating a heading output signal based on heading information when reliable heading information is received over the at least one interface; the heading calculator generating the heading output signal based on data from the memory device regarding previously reliable heading information and an output of the at least one set of gyroscopes and accelerometers when reliable heading information is not received over the at least one interface.

Abstract: An aircraft inertial system comprises at least two inertial reference units (IRU) that provide a first set of inertial signal data for an aircraft and at least two attitude heading reference systems (AHRS) that provide a second set of the inertial signal data for the aircraft. At least one primary flight display receives the first and the second sets of the inertial signal data, and a standby flight display receives at least the second set of the inertial signal data from at least one of the AHRS. When a single fault condition occurs, the primary flight display continues to operate with fail-operational redundancy from at least three independent sources of the inertial signal data comprising one or more IRU and AHRS combinations. The standby flight display will operate using a different source of the inertial signal data than the source of the inertial signal data for the primary flight display.