*R. The point of definition of mean time. As it is directly opposite to mean Sun, in Equinoctial, its position is that of mean Sun plus or minus 12 hours of R.A. Rabbet. Cut-away part in stern, sternpost or keel of a wooden vessel, for bottom planking to fit into.
Rack Bar. Name sometimes given to the bar used in a Spanish windlass.
Rack Block. Several sheaves fitted into one block of wood and used as leads for running gear.
Racking. Binding together two ropes by passing a smaller rope alternately over and under each of them. 2. The smaller rope used when racking.
Racking. The distorting of a ship's transverse shape through undue strain.
Racking Strain. Excessive stress that alters or distorts a vessel's transverse shape.
Racon. A radar beacon which transmits a signal on receiving a radar signal from a ship and thus shows the range and bearing of the racon on the ship's display.
Radar. Electronic system by which the bearing and distance of an object are found by the emission of a radio pulse, an observation of the direction of its return and the measurement of the time elapsed between emission and return.
Radar Beacon. A radio transmitter transmitting signals at radar frequencies which can be received and identified by a ship's radar set.