Aeronautic Instruments. Section IV : Direction Instruments (1923)
NASA Technical Reports Server (NTRS) · leaf 26
4 millimeters at the bottom. (See illustration of rotating element and bearing post at right of fig. 1.) The markings are found upon the exterior face of the cone, which has a depth of 10 millimeters along a generating element. The card is lettered at the cardinal points with luminous material and… … Fig. 1.—General Electric air compass, Type B. The pivot is of special alloy and rests in a sapphire cup mounted upon a bearing post attached to the lower surface of the bowl. The pivot is prevented from leaving its socket by a split cage, the two halves of which are screwed to the bearing post, and…
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