Spindrift states: Force 8, defined as "Gale". Wind speed 39-46 mph, equal to 34-40 knots. Inland, twigs break off trees; progress generally impeded. At sea, moderately high waves of greater length; edges of crests begin to break into spindrift; foam is blown in well-marked streaks along the direction of the wind. Relatedly, "spindrift" can also be used to describe fine sand or snow that is blown off by the wind. "Spindrift" is a southern English word, "Spoondrift" a northern or Scottish word. The Scottish word "spoondrift" can be used to describe fine snow that is blown off the hills by the
Wind tunnel high Reynolds number, since it is not practical to obtain full scale Reynolds number by use of a full scale vehicle. V/STOL tunnels require large cross section area, but only small velocities. Since power varies with the cube of velocity, the power required for the operation is also less. An example of a V/STOL tunnel is the NASA Langley 14' x 22' tunnel. Aircraft have a tendency to go to spin when they stall. These tunnels are used to study that phenomenon. Automotive wind tunnels fall into two categories: Wunibald Kamm built the first full-scale wind tunnel for motor vehicles.