Downloaded from https://www.everyspec.com MIL-STD-81.OD 19 July 1983 e. onmenta1 engineering sDecialist. One whose principal work assignment lies in the tethnical area of’natural and induced environments and their relation to military equipment. A person who has expertise in measuring and analyzing field.environmental conditions, formulating environmental test criteria, specifying laboratory simulation of environments, and evaluating the effects of environments on equipment. f. functlfm. A climatic or mechanical environmental input to an item of equipment that affects its design, service life, or ability to function.
(Also referred to as en environmental condition or an environmental stress.) .. g. Her metic seal. A permanent air-tight seal. h. Xk3uced environment. A local environmental condition that is predominant1y.man-made or.equipment-generated. Also refers to any internal condition that results from the combination of natural forcing functions and the physical/chemical characteristics of the.equipment. i. Life cvcle history. A time history of events and conditions associated with an item of equipment from its release from manufacturing to its ultimate removal from service. The,life cycle should include the various, phases that an item will encounter in its life, such as:
handling, shipping, and storage prior to use; mission profileq,.whilein use; phases between missions; such as stand-by.or storage, tranafer to and from repair sites and alternate locations; and geographical locations of expected deployment. j. Ii&3ion Drot2.L.e. “That portion of the life cycl’eassociated with a . specific operational mission. k. Uat.fwI. Any vehicle, surface, o-r“mediumthat carries the equipment. For example, an aircraft is the carrying platform for internally installed avionics equipment and externally mounted stores. The land is the platform fcr a ground radar set, and a man for a hand-carried radio. 1. ‘Platform.environment.
The environmental conditions an equipment experiences ag a result of being attached to or loaded onto a platform. The platform environment is a result of forcing functions induced or modified by the platform and any on-board.environmental control systems. m. Ta iloring. The process of chocsing or altering test procedures, conditions, values, tolerances, measures of failure, etc., to simulate or exaggerate.. the effects of one or more’forcing functions to which an item will be subjected during its life cycle.
The.tailoring process, broadly speaking, also includes the engineering tasks and preparation of planning dccuments to assure proper’consideration of environments throughout the life cycle. ,. n. T= level. Tbe value at which a test condition is set. 0. Test method. The criteria and procedures used to formulate-an environmental test. Test ethods.are identified by environment (or? combinations) in section 5 of this document. 3