This Is Why Cruise Ships Go So Slow

If you’ve been on a cruise ship or are planning to go on one, you’ve probably noticed that it takes a long time to complete the journey. Understandably, water transportation is very slow, but cruise ships, in particular, seem to take their time. Is this low speed an intentional choice, or are they incapable of moving faster?

Cruise ships go slow because of the nature of the ship and ocean travel, emergencies, or issues with the ship. They may also intentionally slow down due to their itinerary. The average speed of a cruise ship is 18-20 knots (33-37 kph), but the fastest cruise ship can reach up to 30 knots (56 kph).

In the rest of the article, I will discuss in detail all the factors that affect the speed of a cruise ship and what the top speed of a cruise ship is. Furthermore, I’ll explain how cruise ships might travel at different speeds at night, what the fastest cruise ship in the world is, and more.

Factors Affecting Cruise Ship Speeds

The average speed of most cruise ships is 18 to 20 knots (33-–37 kph). Knots are units that measure the speed of boats and ships. One knot is equal to one nautical mile per hour, or 1.15 standard miles (1.85 km) per hour. 

As you can see, this speed seems pretty low, compared to even the slowest trains in the country, but it’s important to keep in mind all the factors that contribute to it. Some of these factors are related to the nature of ships and are perfectly normal, while some are related to potential problems. Others are intentional and related to the nature of cruises.

Weight and Friction

Like every other large ship, cruise ships are inherently slow because they are giant, heavy vessels trying to move through the water. The friction that water provides, combined with the ocean waves and the significant weight, creates unfavorable conditions for fast movement.

There are several ways in which modern ships have managed to improve their speed and efficiency, including recent technologies like air lubrication. However, it is reasonable not to expect high speed from a large ship moving through water.

Bad Weather 

Ideally, all cruise ships would sail during the sunniest and calmest days of the year, but, sometimes, the weather has other plans. When the weather conditions worsen, they reduce visibility and cause rough waters, making it more challenging to sail smoothly. As a result, your cruise ship might slow down until the sky is clear again.

Problems With the Ship

A cruise ship may be moving slower than usual because of problems such as cavitation. Cavitation occurs when there is low pressure around the boat propellers, causing water bubbles to damage them while spinning. This can cause much more severe issues down the line, but one of the early signs is slower movement due to lower efficiency.

Low Fuel Levels

Moving such a large and heavy ship through water requires massive amounts of energy, which is provided by fuel. The faster the cruise ship moves, the more the water will resist the movement, and the faster the fuel will burn and run out. Sometimes, if the ship is low on fuel, it makes sense to slow down to reduce consumption.

Unforeseen Circumstances

The cruise ship might need to slow down when emergencies happen. Sometimes, someone may fall overboard, causing the ship to slow down and even stop to rescue the passenger. The ship may then speed up to recover the time lost, so it can catch up to the itinerary.

Following the Itinerary 

Sometimes, cruise ships move slower than other types of ships because they do so intentionally. Even when the fuel levels are high and there is no issue with the ship, the Captain can decide to slow down because he wants to, for different reasons.

Cruise ships have many stops along the way, but these stops are scheduled. If the cruise ship is ahead of schedule and could arrive sooner than predicted at the port, the Captain may decide to slow down in order to arrive at the right time.

The captain stalls because the longer the ship stays docked at the port, the more money the company has to pay. As a result, your ship may slow down so it can enter the port at the right time to avoid unnecessary docking fees.

Other times, the ship might slow down simply for the passengers to enjoy the good weather or see beautiful scenery. Cruises allow these delays and stop to satisfy all the passengers, especially when the next port is nearby.

What Is the Fastest a Cruise Ship Can Go?

Having considered all these factors, cruise ships can still go fast. While the average speed is around 20 knots (37 kph), cruise ships can go faster if they have to. For instance, a cruise ship might need to move faster to outrun a terrible storm, or the Captain may want to speed up to make up for previous delays.

The maximum speed of most cruise ships is around 30 knots or 34.5 miles (55.5 km) per hour. As I explained above, cruise ships generally don’t reach this speed because it consumes a lot of fuel.

What’s the Fastest Cruise Ship in the World?

As of 2022, the fastest cruise ship in the world is Queen Mary 2, which was initially built as an ocean liner. Ocean liners are typically faster than cruise ships, which may explain why Queen Mary 2 is so fast.

Queen Mary 2 can reach 30 knots (56 kph) as a top speed, but it can sustain a speed of 26 knots, which, as you know by now, is higher than most typical cruise ships. 

What Distance Can a Cruise Ship Cover in a Day?

There are many factors that can affect the distance traveled by a cruise ship in a day. As I explained, everything from emergencies to the weather can affect the ship’s speed, causing it to travel more or less than predicted in one day. However, a theoretical calculation can be made.

Theoretically, let’s say a cruise ship is traveling at 18 knots, which means 18 nautical miles per hour. Let’s assume that the speed stays constant, as there are no reasons to slow down. This means that in 24 hours, traveling at 20 nautical miles per hour, the cruise ship will cover 432 nautical miles or 497 miles (800 km) in one day.

Do Cruise Ships Slow Down or Speed Up at Night?

You may have heard one version or the other (we wrote about it here!). Some think cruise ships slow down at night to disturb the sleeping passengers as little as possible, while others say they have noticed that the cruise ship moves faster at night.

Most cruise ships try to keep more or less the same speed at night as they do during the day, but they might slow down a bit. The usual speed at night for a cruise ship might be between 14 and 20 knots, as opposed to the typical 18 to 20.

The reason why some people believe that cruise ships move faster during nighttime is that cruise ships usually don’t stop at ports during the night. When the ship approaches the port during the daytime, it naturally slows down, causing the passengers to notice the difference.

Final Thoughts

Cruise ships usually travel at pretty low speeds, around 20 knots. They are naturally slow because of their weight and the fact that they travel on water, but they can also slow down because of the weather, emergencies, or ship problems. Additionally, the Captain may intentionally slow down to follow the cruise’s itinerary.

Cruise ships maintain more or less the same speed at night, although they might slow down a bit. The fastest cruise ship in the world is Queen Mary 2, which travels at a top speed of 30 knots, the highest a cruise ship can go.

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