Stability, Lateral—The stability of an aeroplane about its longitudinal axis, and without which it has no tendency to oppose sideways rolling.
Stabilizer—A surface, such as fin or tail-plane, designed to give an aeroplane inherent stability.
Stall, to—To give or allow an aeroplane an angle of incidence greater than the “maximum” angle, the result being a fall in the lift-drift ratio, the lift consequently becoming less than the weight of the aeroplane, which must then fall, i.e., “stall” or “pancake.”
Stress—Burden or load.
Strain—Deformation produced by stress.
Side-Slip, to—To fall as a result of an excessive “bank” or “roll.”
Skid, to—To be carried sideways by centrifugal force when turning to left or right.
Skid, Undercarriage—A spar, mounted in a fore and aft direction, and to which the wheels of the undercarriage are sometimes attached. Should a wheel give way the skid is then supposed to act like the runner of a sleigh and to support the aeroplane.
Skid, Tail—A piece of wood or other material, orientable, and fitted with shock absorbers, situated under the tail of an aeroplane in order to support it upon the ground and to absorb the shock of alighting.
Section—Any separate part of the top surface, that part of the bottom surface immediately underneath it, with their struts and wires.