Aircraft display devices

A display device for an aircraft, comprising:

• (A) a circular array including a multitude of selectively activatable display elements, the array having an outer periphery bounding a circular display area having a center,
• (i) the elements being disposed in equally angularly spaced lines extending radially from the center of the display area, each radial line having at least four, and the same number of, elements with corresponding elements in the different radial lines at the same radial distance from the center of the display area,
• (ii) the elements along each radial line occupying a major proportion of the radial line,
• (iii) each said element subtending an angle of substantially the same magnitude at the center of the display area and having a radial dimension of substantially the same magnitude, and
• (iv) each said element being arranged to be substantially contiguous with each adjacent element;
• and
• (B) means for selectively activating said display elements in accordance with aircraft attitude whereby the selected elements form a visible area and line pattern indicative of the aircraft attitude, said means for selectively activating said display elements activating elements in a segmental area defined by a chord joining extremities of an arcuate portion of the outer periphery of the array, said chord moving with respect to the array in a direction normal to its length to depict changes in pitch of the aircraft and changing its angle with respect to the array to depict changes in roll of the aircraft.