What are those white spheres on top of cruise ships? How fast is a knot? What is the difference again between port and starboard? On this page it will all be explained!

Maritime information

The bridge

Satellite dish

Lifeboats and liferafts

The place from where the ship is steered. Here you will find the captain and the officers.

The white spheres on the top deck of a cruise ship are satellite dishes in a spherical housing. They provide television and radio signals on board.

On both sides of the ships hang yellow or orange lifeboats that have space for all passengers and crew members on board. The lifeboats can still be subdivided in ‘normal lifeboats’ and ‘tenders’. A tender has been designed in such a way the it can be used to transport passengers to the shore when a cruise ship has to anchor. It can be seen as a taxi. Apart from the lifeboats there are also liferafts on board that can fit a minimum of 25% of all persons on the vessel. That means that the rescue capacity of a cruise ship is a quarter bigger than the total number of people on board. The liferafts are stored outside on deck in white plastic barrels that open when they make contact with water.

Funnel (& environmental efforts)

This is the exhaust of the ships’ engines. Over the last few years there has been a lot of media attention regarding the air pollution by cruise ships. Although the impression is given that nothing is being done to reduce emissions this is not true. The emission of sulfer dioxide (SOx) and nitrogen oxide (NOx) has already been reduced on the North sea and the Baltic Sea by strict regulations. Apart from that the cruise and ferry branch is also experimenting with new possible fuels like LNG and hybrid-technology. No other maritime branch is this progressive in this search. While looking at environmental pollution one should also not excessively focus on the cruise ships. Currently a total of around 100.000 ships are sailing around the world, but only around 400 of those are cruise ships.

Mast

At the front of the ship, behind the bridge, you can find the mast. On it are the radars and several flags. The mast must also always fly the flag of the waters the ship is currently in. A ship that is on its way to Antwerp will exchange the Dutch flag for the Belgian flag at the border.

Propellers or Azipods

Cruise ships can be propelled in two ways. There can be made use of one or more static propellers behind which a rudder can be found. This is the classical way and is still widely used by ship builders. A second possibility is to replace the propeller and the rudder by an Azipod. This is a propeller that is able to turn 360° which makes it possible to steer the ship directly sideways. When the Azipods work together with the bow thrusters (propellers at the front of the ship) it is possible to turn the ship around in a perfect circle.

The cruise ship

Bulbous bow / Bulb

The bulbous bow or bulb can be found at the front of the ship, right below the water surface. It is a spherical projection to reduce the resistance of the water on the ship while it sails. A ship creates a bow wave on its own, but due to the bulb a second wave is created right in front of the first one which cancels out the first one. This reduces the water resistance on the ship, which can be translated in using less fuel, but not every ship has a bulb. Older ships often don’t have it because the technique did not yet exist when they were built. But some new ships are also built without, or with an altered bulb. That is because a bulbous bow is only effective at certain speeds, which cannot always be maintained.

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The bridge

Satellite dish

Lifeboat

Lifeboat/Tender

Liferaft

Funnel

Mast

Propeller

Azipod

Bulbous bow / Bulb

Port & Starboard

In the maritime world one does not speak of left and right, but of port and starboard. Both are also given a specific colour: red and green. Port = Left & Red Starboard = Right & Green

Andere maritieme termen

Pilots

A pilot is a specialist of a specific stretch of water. Due to their knowledge and experience they advise captains on board the ship about the speed, heading, currents, etc. That way it is made sure that the ships can reach their destination without a problem. Almost all large sea ships are obligated to have at least one pilot on board, but often there is a second pilot on board during river sailings. The reason for the second pilot on the river Scheldt is because it’s one of the most difficult rivers to navigate due to treacherous currents and its many sandbanks. Apart from that it is also a very busy river. At sea there are two pilot stations: De Wandelaar in the West and Steenbank in the East. At the Scheldt estuary in Flushing there is a third pilot station for ships that sail the river Scheldt.

Convert knots to km/h

1 kts = 1,85 km/h 2 kts = 3,70 km/h 3 kts = 5,56 km/h 4 kts = 7,41 km/h 5 kts = 9,26 km/h 6 kts = 11,11 km/h 7 kts = 12,96 km/h 8 kts = 14,82 km/h 9 kts = 16,67 km/h 10 kts = 18,52 km/h

11 kts = 20,37 km/h 12 kts = 22,22 km/h 13 kts = 24,08 km/h 14 kts = 25,93 km/h 15 kts = 27,78 km/h 16 kts = 29,63 km/h 17 kts = 31,48 km/h 18 kts = 33,34 km/h 19 kts = 35,19 km/h 20 kts = 37,04 km/h

21 kts = 38,89 km/h 22 kts = 40,74 km/h 23 kts = 42,60 km/h 24 kts = 44,45 km/h 25 kts = 46,30 km/h 26 kts = 48,15 km/h 27 kts = 50,00 km/h 28 kts = 51,86 km/h 29 kts = 53,71 km/h 30 kts = 55,56 km/h

Did you know? The record for the fastest Ocean Liner is held by the American ship SS United States. In 1952 the ship crossed the Atlantic Ocean with an average speed of 34,51 kts or 63,91 km/h. At that speed it took only 3 days, 12 hours and 12 minutes.

The top speed of modern cruise ships averages between 20 and 24 knots, but there are also exceptions to this rule. The 2003 built Ocean Liner RMS Queen Mary 2 can still get a speed of 30 kts or 55,56 km/h.

In the maritime world the speed of a ship is not expressed kilometres per hour (km/h), like it is the case with cars and trains, but in knots. When you multiply the number of knots x1,85 you get the speed in km/h.

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