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of the Earth creates a shadow zone from the sun. . Line-of-sight transmission path means that obstacles and terrain can create shadow zones.
shaft /.ɑft/ noun a long, generally cylindrical bar, especially one that rotates and transmits power . engine drive shaft . propeller shaft
shaft horsepower /.ɑft h.spaυ./ noun the unit used for stat-ing the power delivered to the shaft of a turboshaft or turboprop engine. Abbre-viation SHP
shaker /.e.k./ noun a device which shakes or vibrates violently . Large air-craft use a stick shaker to supplement the natural stall warning of buffet.
shallow /.l.υ/ adjective not deep . shallow angle small angle

shallow depression /.l.υ d.
pre.(.)n/ noun an area of slightly low relative atmospheric pressure
shape /.e.p/ noun form . The shape of an aircraft is determined by the requirement to provide an aerodynamic lift force great enough to support the weight of the aircraft and payload whilst in flight.
sharp /.ɑp/ adjective 1. thin and capable of cutting or piercing . If a piece of thermosetting plastic is hit hard enough, it breaks into pieces with straight sharp edges. 2. clear . The sharp setting means the bandwidth is reduced to 1kHz (kilohertz) to minimise noise or interference. 3. clear and dis-tinct . Cumulus clouds have sharp out-lines. 4. sudden and acute . a sharp increase a sudden large increase