Robinson's Disengaging Gear. Releasing gear for ship's boats. Boat's falls are held by hinged hooks fitted in the slings. On release of a tackle these hooks are free to open upwards and allow boat to drop into the water.
Rockered. Said of a keel whose lower edge sweeps downward as it goes aft.
Rocket Apparatus. Line-carrying rockets and apparatus for firing them and aligning them so that a line can be carried to a wrecked vessel in the vicinity of the shore. Breeches buoy can be used for removing persons from wreck. Provided at all critical points around coasts of British Isles.
Rogue's Yarn. Coloured thread inserted in each strand of a rope issued by H.M. Dockyards. Colour varies according to the dockyard issuing the rope. Indicates that the rope is Admiralty property.
Roll. Rhythmic inclination of a vessel from side to side when in a seaway.
Roll Cumulus. Name given to cloud when disposed in long parallel rolls.
Rolled Section. Sectional shape of a steel bar or girder when the shape was imparted as the bar passed through the rolling mill.