- conical surface
- A surface extending from the periphery of the horizontal surface outward and upward at a slope of 20 horizontal to 1 vertical for a horizontal distance of 4000 ft. It is an imaginary surface, in which any object that projects above the surface is considered an obstruction to air navigation.

*Aviation dictionary.
2014.*

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**Conical surface**— A circular conical surface In geometry, a (general) conical surface is the unbounded surface formed by the union of all the straight lines that pass through a fixed point the apex or vertex and any point of some fixed space curve the directrix… … Wikipedia**Conical surface**— Conic Con ic, Conical Con ic*al, a. [Gr. ?: cf. F. conique. See {Cone}.] 1. Having the form of, or resembling, a geometrical cone; round and tapering to a point, or gradually lessening in circumference; as, a conic or conical figure; a conical… … The Collaborative International Dictionary of English**conical surface**— noun mathematics : the surface generated by a moving straight line which always passes through a fixed point and intersects a fixed curve … Useful english dictionary**Conical**— Conic Con ic, Conical Con ic*al, a. [Gr. ?: cf. F. conique. See {Cone}.] 1. Having the form of, or resembling, a geometrical cone; round and tapering to a point, or gradually lessening in circumference; as, a conic or conical figure; a conical… … The Collaborative International Dictionary of English**Conical pendulum**— Conic Con ic, Conical Con ic*al, a. [Gr. ?: cf. F. conique. See {Cone}.] 1. Having the form of, or resembling, a geometrical cone; round and tapering to a point, or gradually lessening in circumference; as, a conic or conical figure; a conical… … The Collaborative International Dictionary of English**Conical projection**— Conic Con ic, Conical Con ic*al, a. [Gr. ?: cf. F. conique. See {Cone}.] 1. Having the form of, or resembling, a geometrical cone; round and tapering to a point, or gradually lessening in circumference; as, a conic or conical figure; a conical… … The Collaborative International Dictionary of English**conical projection**— /ˌkɒnɪkəl prəˈdʒɛkʃən/ (say .konikuhl pruh jekshuhn) noun a map projection based on the concept of projecting the earth s surface on a conical surface, which is then unrolled to a plane surface. Also, conic projection … Australian English dictionary**Surface of revolution**— A surface of revolution is a surface created by rotating a curve lying on some plane (the generatrix) around a straight line (the axis of rotation) that lies on the same plane. Examples of surfaces generated by a straight line are the cylindrical … Wikipedia**Conical intersection**— Ideal Conical Intersection In quantum chemistry, a conical intersection of two potential energy surfaces of the same spatial and spin symmetries is the set of molecular geometry points where the two potential energy surfaces are degenerate… … Wikipedia**Conical mill**— A conical mill (or conical screen mill) is a machine used to reduce the size of material in a uniform manner. It is an alternative to the hammermill or other forms of grinding mills. The conical mill operates by having the product being fed into… … Wikipedia