congested waters, collision, grounding, navigation, gong, cargo winches, cranes,
anchor, tugboats, seamen, port, straits, harbour, harbor, pilot, standby,
Tugboats have powerful engines and propellers
Ships without bow thrusters are not able to move sideways on
Communication from the steering gear room that everything is ready
Synchronizing additional generators to prevent
Maneuvering at harbor
When the ship arrives at a harbor port, or going through
narrow straits, the ship has to prepare for maneuvering. This is a critical period as any loss of propulsion, or steering, can lead to collision, grounding, or other damage to the ship.
The navigation officer on the bridge will give the engineer in the engine room one-hour
standby notice to prepare for maneuvering while the ship is still proceeding towards the port. The messages are all recorded in a maneuvering book, indicating the exact time the notice was given. Later on, throughout the maneuvering, all the orders through the engine telegraph are also recorded in the book.
The engine telegraph is a device with a pointer and handle, which is used to convey orders between the bridge and the engine room. Orders like "dead slow ahead" "half astern", "full ahead", "stop" are some examples of orders. When the personnel on the bridge move the handle of the telegraph on the bridge, there is a corresponding movement of the pointer of the engine room telegraph together with the sound
of a gong. The engineer maneuvering the engine at the engine room on hearing the gong and the movement of the pointer will acknowledge the order by moving the handle to the same indication. The gong will then stop sounding.
The engineer who acknowledges the order has to adjust the engine accordingly, either speeding up, slowing down, stopping, or starting. All the engine movement is recorded in the maneuvering book.
During the one-hour notice for maneuvering, the engineer has to prepare the engines for maneuvering. Extra electrical generators have to be started up and synchronized so that there is sufficient electrical capacity to prevent blackout due to overloading of the generators. At this period, many other machines will be started up, e.g. mooring winches, cargo winches, cargo cranes, anchor winches, and others.
For main diesel engines, the starting air supply is opened up. The air reservoirs are shared so that the maximum capacity of air is available for engine starting. The main engine fuel oil are gradually changed over from heavy C oil to light diesel engine, anticipating the loss of heating of the fuel oil due to the slowing down of the main engines.
As the ship draws near to port, the order may come from the bridge to slow down to certain speed. Usually the ship will stop to pick up a pilot to assist in the maneuvering. The pilot will have local knowledge on the location of markers, shallow areas, tides, and currents. The pilot will give the orders to be transmitted to the engine room from then onwards.
Usually tugboats will assist the ship to go along side the wharves at the port. These take orders from the pilot. The seamen at both fore and aft of the ship will throw up rope lines to the shore men. The ship will go ahead, astern in small steps and eventually be tied up securely at the wharf.
Once the ship is tied up the final order from the bridge will be "Finished with Engines".
On departure from port, again preparations are made to the equipment to warm up, testing of telegraph, telephone, testing engines, etc. The maneuvering follows much the same as arrival.