Light aircraft navigation apparatus

Claim 1

An improved gyroscopically stabilized artificial horizon instrument for an aircraft capable of both displaying an artificial horizon and generating a signal representative of flight direction, said instrument comprising: (a) a frame defining an enclosed space and mounted within the aircraft; (b) a gimbal structure mounted on the frame pivoting around a first axis extending lengthwise of the frame; (c) an energized gyroscope mounted for pivoting about a second axis passing through the gimbal and having a housing through which said second axis extends, said second axis being perpendicular to the first axis; (d) artificial horizon display means operatively associated with said frame, gimbal structure, gyroscope and housing for displaying an artificial horizon in response to changing positions of the aircraft during flight; (e) an earth magnetic field sensitive flux sensor mounted on said gyroscope housing in a position which permits said earth magnetic field sensitive flux sensor to remain level during changing positions of the aircraft and operable to produce a signal indicative of the direction in which said aircraft is headed in response to changing positions of the aircraft during flight relative to the earth's magnetic field; (f) converter means for receiving said signal from said sensor and converting said signal to a form suited for digital display; and (g) display means operable to receive and display said converted signal as a visual display of direction and located on the aircraft at a location which enables a pilot of the aircraft to view both the artificial horizon display and a digital display of direction.