to keep the deck hatches at a required level for dockside loading.
The huge cargo area is divided into five holds. A series of power-actuated gates in each hold feeds pellets or coal onto a conveyor belt that lies beneath the entire length of the cargo hold area. The De Lancey's unloading system is capable of discharging pellets at the rate of 10,000 tons per hour. The 260-foot boom can swing to either side for piling cargo ashore under high-speed unloading conditions.
Main propulsion power for the De Lancey is provided by two 8,560-bhp Colt-Pielstick diesel engines. Each engine is directly connected to a four-blade, 17½-foot-diameter controllable-pitch Bird-Johnson propeller through a specially designed reduction gear and shafting system.
Designers of the De Lancey were most concerned with two aspects of the main drive system— reliability and low maintenance. The result is a simple, unencumbered drive system capable of delivering power to the propellers efficiently and in a minimum of space.
The arrangement of completely independent drive systems for each engine optimizes overall reliability; if for some reason one engine is nonoperational, the other can still power the ship. Four 800-kw, 480-volt main electrical generators are driven by separate Caterpillar diesel engines.
The De Lancey has a maximum capacity of 152,000 gallons of heavy fuel oil for main propulsion, and carries 31,000 gallons of light diesel oil fuel for generator, heater, and boiler service.
Each controllable-pitch propeller assembly is fitted with four stainless-steel movable blades. An automatic pitch-control system hydraulically changes propeller pitch according to engine speed to provide for optimum running economy and to prevent overloading and stalling the engines when the vessel is heavily loaded at low speeds.
Single-lever controls in both the pilothouse and engine room provide for combined control of engine speed and propeller pitch. Provision is also made for a split control of speed and pitch from the pilothouse and engine room. Separate control units connected to the central pilothouse unit are located on both the port and starboard bridge wings.
Maneuvering the huge 1,000-footer is simplified by the twin screws and the arrangement of a rudder behind each propeller. The ship also can be steered by varying the speed of each engine. A 1,500-hp Bird-Johnson electrically driven bow thruster facilitates docking.
Reversing is accomplished through the controllable-pitch propellers. The onboard St. Louis ship F.A.S.T. sewage treatment plant, which meets stringent federal standards, produces completely clean effluent for discharge, or for temporary holding while the vessel is in waters where discharge is prohibited by local regulations.