MIL-HDBK-143A
destructor - A device which employs explosives or other means to intentionally destroy a
missile or a component thereof if the vehicle's flight is to be cut short, for safety or other
reasons.
destruct system - A system which, when operated by external command or preset internal
means, destroys the missile or similar vehicle.
diergolic (non-hyopergolic) - Liquid Propellants, oxidizer and fuel, which do not burn
spontaneously when mixed, but which require an igniter system.
dihedral angle - The angle, usually the upward angle, between the plane of an aircraft or
missile wing or other control surface and a horizontal plane at the root of that wing or surface.
dipole antenna - An antenna comprising a straight conductor, having an overall length of one
half wavelength or less, connections to which are made at the center. It responds to waves
polarized along the axis of the conductor, and is used at short wavelengths for discriminating
between waves of polarizations.
directional antenna - An antenna which radiates or receives radio signals in some directions
more efficiently than in others.
directional stability - The characteristic of an aircraft or missile configuration which causes
the vehicle to right itself from a side-slip or yawing condition.
directivity - That characteristic of an antenna which enables it to radiate or receive more
energy in some directions than in others.
disarm - To render a missile warhead incapable of exploding.
disassociation - The breaking down of the atmosphere into atomic molecules of nitrogen and
oxygen caused by the passage of a high speed missile through the medium.
discone antenna - An antenna which is formed by a disc and a cone whose apex approaches
and becomes common with the outer conductor of the coaxial feed at its extremity.
dispersion - 1. In rocketry, the deviation of a missile from its prescribed flight path;
specifically, circular dispersion. 2. A measure of the scatter of data points around a mean
value or around a regression curve.
distance measuring equipment (DME*) - A radio navigation aid, which provides distance
information by timing the round-trip of a radio signal fromaan interrogator to a transponder.
dive angle - The angle between the missile center line and the horizon at target impact. Cf:
impact switch
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