Crane lighter buoyancy system - has supplementary tanks coupled to bow and stern during transit and manoeuvred by pumping out and flooding

摘要

The crane lighter has detachable supplementary buoyancy tanks and a jib (14) overhanging one end (12) of the rectangular pontoon hull (10). At this end, provision is made along the sides (26, 28) for securing supplementary buoyancy tanks (30, 32) if necessary to increase the crane lift. Connecting fittings are such that they are engaged or disengaged by pumping out or flooding tanks. When not in use the tanks are secured to the pontoon ends, or both to one end, to support the lowered jib. To improve pontoon handling in this condition, one or both tanks can have a partially sloping bottom.