A gyro system is disclosed in which the system is brought from an "off" position back to full operating speed and known orientation in a short time without requiring any external signal for orientation verification. A fast start procedure is disclosed in which the last known position is employed as the actual starting position of the gyro as well as an aligned procedure in which the last known position is employed as a reference point for faster alignment.

A flight director type of aircraft control or guidance display and mechanism for pilot reference which provides a composite integrated display of roll, pitch and heading with a sensing relationship approximating what the pilot sees through the windshield in the real world environment. The visual cue relationship is retained when the display is viewed during flight in obscure visibility with resulting elimination of vertigo and disorientation. The display is remote from its sensors of aircraft control and guidance and may be positioned in a head erect location in the instrument panel. The electro-mechanical display of roll, pitch and heading embodies a roll symbol which is positioned in front of a rotating dial displaying heading that enables control coordination during turns. An associated horizon bar remains parallel to the display base while rising and falling past the roll symbol to indicate a glide or climb respectively. The integrated indicia of aircraft control are closely associated with guidance indications to facilitate effective and precise control or guidance of the aircraft in the approach/landing.

A combination directional gyro and navigation radio indicator instrument for use in aircraft which provides a display of compass card, selected course pointer, course deviation indicator, to-from indicator, and glide slope indicator in a unique presentation. The compass card is directly driven by the directional gyro, and the selected course pointer normally rotates with the compass card when it rotates, but can be de-clutched for selection of a new course. The selected course signal is obtained by attenuating, amplifying, and phase shifting the reference signal from a navigation radio such that it can be sent to the rotor of a control transformer which is geared to the compass card. The resulting stator signal is then amplified and sent to the rotor of a differential resolver which is geared to the course selector pointer. The control transformer and the differential transformer rotors turn in opposite directions such that the reference signal does not change when the compass card and the course selector pointer move together, but does change when the course selector is de-clutched and moves independently of the compass card. The resulting signal from the stator of the differential transformer is therefore an electrical representation of the selected course. This signal is then sent back to the navigation radio where it is compared to the signal representing the actual course of the aircraft that is received from a stationary navigation radio transmitter (VORTAC).

A horizontal situation indicator having a heading card direct-driven by a directional gyro is provided. Relative positioning of the heading card and one or more navigation indicators is determined by sensing an electrical differential between a transducer associated with a heading card and a transducer associated with each navigation indicator. Spring-loaded clutch mechanisms are provided to allow adjustment of the navigation indicators without applying a torque to the heading card and gyro.