waveform analyzer. An electronic instrument that measures the frequency and amplitude of the various components of a complex electromagnetic wave.
wave guide. A hollow transmission line through which high-frequency electromagnetic waves are directed.
wavelength (λ). The distance between a peak or a trough of an electromagnetic wave and the corresponding peak or trough in the next cycle of the wave. Wavelength is inversely related to the frequency of the wave.

wave soldering. A method of soldering components to a printed circuit (PC) board. All the components are assembled on the PC board, and the side of the board on which the copper strips are formed is treated with flux.
A tank of molten solder is vibrated so waves form on the surface of the solder, and the board is passed over the solder so the tip of the waves touch the fluxed copper strips. All the component leads protruding through the board are soldered to the copper strips.
waypoint (aerial navigation). The location on a navigational chart to which a VORTAC station has been electronically moved by an Area Navigation (RNAV) system. A waypoint is located by keying in the radial from the VORTAC station on which the waypoint is to be located, and the distance in nautical miles from the station along the selected radial.
By using waypoints, rather than flying directly to the physical station, a flight can be made in a straight line, and radio navigation can be used directly to a destination having no radio facility. A waypoint may be defined relative to a VORTAC station or in terms of latitude/longitude coordinates.
wear pads (aircraft brake component). Steel pads riveted to the surface of the stationary disks of a multiple-disk brake. These pads wear away by the abrasive action of the sintered material on the rotating disks as the brake is used. It is more economical to replace the wear pads than to replace an entire disk.
weather. The state of the atmosphere, mainly with respect to its effects on life and human activities. Weather differs from climate in that it refers to instantaneous conditions or short-term changes.
weather advisory. An expression of hazardous weather conditions not predicted in the area forecast, as they affect the operation of air traffic and as prepared by the National Weather Service.
weber. The basic unit of magnetic flux. One weber is the amount of magnetic flux in one turn of wire needed to produce one volt of electrical pressure, when the current flowing through the wire is reduced evenly at the rate of one ampere per second.
web of a beam. The part of a structural beam between the caps. A beam is designed in such a way that a bending load is carried as a tensile load in one of the caps and a compressive load in the other. The web between the two caps is subjected to a shear load much lower than the tensile or the compressive load. The web of a structural beam is usually thinner than either of the caps.