221 sub-beam
possess sufficient strength in its pure state for structural uses, but when mixed with zinc, aluminium, and man-ganese it produces an alloy having the highest strength-to-weight ratio of any of the commonly used metals. . high-strength materials materials which are very strong 2. the degree of clarity and volume of a signal . A radio wave loses strength as range increases. 3. the degree of dilution of a liquid . Incorrect mixture strength may cause detonation.
4. intensity of radiation . The strength of the sun’s radiation varies with lati-tude. 5. the speed and force of a wind . High ground will disturb the smooth horizontal flow of air, with the degree of disturbance depending upon the strength of the wind and the roughness of the terrain.
strengthen /stre.θ(.)n/ verb to make strong or stronger . Some alloys are hardened and strengthened by heat treatment. . the wind is strengthening
the wind is increasing in speed
strengthening /stre.θ(.)n../ noun
1. the act of making stronger . Aircraft which require large apertures in the fuselage for freight doors, etc., need increased strengthening around these areas. 2. the fact of becoming stronger
. strengthening of the wind
stress /stres/ noun 1. the load per unit area to which a body that resists distor-tion or change of shape is subjected by internal forces . Turbine blades in the average jet engine vibrate at frequen-cies of 1 million per minute, and in each cycle experience stress. 2. a worried, anxious and tired state brought on e.g. by overwork . He gave stress as the reason for wanting a week off work. 3. emphasis . verb to emphasise . It must be stressed that the description is a model and departures from it often occur.
stretch /stret./ noun a continuous unbroken length . a stretch of coast . verb to extend or enlarge beyond the proper limits . Tensile stress or tension is the resistance of a material to being stretched.
stretching /stret.../ noun extend-ing or enlarging beyond the proper lim-
its . Tensile stress is the resistance to pulling apart, or stretching, produced when two forces in opposition act along the same straight line.
strict /str.kt/ adjective precise, exact
. Fuels for aircraft must conform to strict requirements. . All generator voltages, frequencies and their phase sequence must be within very strict lim-its to ensure proper system operation.
strike /stra.k/ noun an impact or col-lision . verb to hit (NOTE: striking – struck)
stringer /str.../ noun a thin metal or wood strip which goes from one end of the fuselage to the other . Stringers are made of a light alloy material.
strip /str.p/ noun a long narrow piece, usually of the same width from end to end . a strip of paper . verb to disman-tle . After the collision, the engine was stripped down to its component parts.
stroke /str.υk/ noun any of a series of movements of a piston from one end of the limit of its movement to another .