How Cruise Ships Work

Modern day cruise ships are almost like floating cities: they have seemingly endless amenities and dining options while giving passengers little reason to ever even want to go into port when the ship docks. Cruise ships are luxury vacation spots for people around the world because they’re typically all inclusive and provide worry free days at sea where you can relax and escape the worries of every day life. Have you ever wondered how these massive floating cities have come to be, and how they continue to stay afloat when it seems like there’s so much aboard they appear as though they should struggle to stay above water.

How did they come to be?

During the great depression there were a couple shipping companies that were really struggling to keep afloat because the economy was just sinking and the business wasn’t there. From this the idea of transporting  people across great bodies of water instead of just goods was born, and with it came ships like The Queen Elizabeth 2 or the QE2. These ships made popular the idea of luxury sea travel instead of just storing away among some shipping containers.

There are many cruise lines that offer popular destinations around the Caribbean, the Mediterranean and even Alaska, but that one shipping line that started it all still offers the trans-Atlantic voyage that crowds of people originally signed up for.

Keeping Everyone Above Water

The size of cruise lines today will lead anyone to question how exactly they manage to stay above water. A ship built for extensive travel needs to have specific engineering to be able to withstand the weight brought on by passengers, crew members, luggage, food and supplies. In order to stay above water ships use density and buoyancy principles to their advantage. How this works is ships will displace an equal amount of water when they push down against the water, while that same amount of water pushes back up against the ship to make sure it stays afloat.

When looking at the size of ship engineers are much more worried about displacement rather than weight. So in order to make sure it doesn’t sink, the ship has to displace its weight before it’s completely submerged under the water. In simple terms what happens is the ship has to be less dense than the water underneath it. So it’s almost like comparing a bowling ball and a beach ball: a bowling ball can’t displace the amount of water needed for it to float before it is completely submerged so it sinks. However a beach ball is much less dense than the water underneath it so it will float.

Underneath the Surface

There’s a lot going on under the water with the ship to make sure the rest of it stays above the water. Large ships – like cruise ships – often use something called a displacement hull which is actually used to push water out of the way and under the ship to help the ship stay afloat. Often this hull has rounded edges, rather than sharp ones. This helps to minimize force against the ship ultimately allowing for the ship to move along smoothly and without issue. Round bottom hulls, unlike their V shaped counterparts, move through the water rather seamlessly so it makes them extremely stable. This means that passengers on these kind of ships do not often feel any kind of rocking or the typical side to side movement thought of with ships.

The downside to round bottom hulls are that they are typically very slow moving, but when it comes to a luxury vacation cruise stability and smooth sailing is definitely more important than speed so that is why this type of hull is the preferred choice of many luxury cruise lines.

 Under the Water, and Inside the Ship

While the hull helps to provide stability for the ship while it’s traveling, it also gives some protection for the ship from debris in the ocean that can tear apart fiberglass, or even steel. In order to prevent massive damage, or sinking, shipbuilders will usually build something called a double hull in the ship. This is typically built of extra strength steel and is built on the inside of the outer hull. Further they will also install items called bulkheads. Should any damage happen to the hull these bulkheads are vertical dividers that will seal off portions of the hull so that water doesn’t continue to move through the ship and cause it to sink.

Getting from Place to Place

Since these ships are basically floating cities it seems logical that it takes quite a bit of energy to move them from port to port and across bodies of water. Older ships typically used diesel as it was the main source of fuel energy however technology has propelled us forward into other options. Currently cruise ships will use gas turbine or diesel electric engines to keep them moving and for their navigation systems. Most cruise ships use one or the other, however some of the larger ones will use one source for their navigation and systems, while using the other source of energy to propel them along.

Gas turbine engines generate heat which is converted from mechanical energy to electrical energy when compressed air is ignited in a combustion chamber. The hot exhaust is then forced over turbine, which spins to drive the shaft of the ship propelling it forward. Diesel electric engines work in a very similar fashion, except they don’t make use of a turbine but rather use a direct driving system.

All cruise ships – no matter what source of energy is used – rely heavily on propellers to move them forward and backward. Propellers have come a long way: modern day versions are so much better than they were in the days of the Titanic with some of the rotating a complete 360 degrees to make these huge floating cities as maneuverable as possible.

Modern day cruise ships are a true engineering marvel, and it’s really surprising as to how they stay afloat. With technology developments we are moving forward and are well on our way to ensuring luxury sea travel continues to keep its head way above water and come up with new attractions all the time.

Jobs on a Cruise Ship

Cruises today are kind of like floating cities, and cities have a lot of moving parts in order for them to work properly. With that in mind it comes as no surprise that cruises have a lot of jobs in order to ensure they continue to operate as smoothly as possible. So here’s what it takes to make sure your vacation goes off without an issue.

Administration

These are the jobs you might not see unless you have an issue with your cabin or a service you booked for your vacation. These roles typically include Human Resources, Hotel Operations, Guest Services and Information Technology.

Food and Dining

Ensuring all the guests are happy with the food they’re eating is one of the biggest jobs on a cruise ship. Many people go on vacation and make decisions based on food reputations, so these jobs are likely to employ more people than any other area on the ship.

Beauty Services

The spa on a ship is also an area that people will read reviews on and potentially write reviews on. A ship will employ hair stylists, makeup artists, massage therapists, personal trainers and fitness instructors. These people are specialized – like all others – in these areas and they will be able to provide services to help guests relax and make the most out of their vacation.

House Keeping

This is one of the areas that is likely the most obvious to the guests. They will see housekeeping changing the sheets, cleaning up the room and bringing you fresh towels every day. These people are very much so frontline staff and can also be responsible for making or breaking the experience a guest has.

Gift Shops

There’s a lot of shopping available on a ship, and staffing those stores is another big task. It isn’t just about putting a body in the store: the people need to know the product they’re selling. Often times the stores are very, very high end: Kate Spade, Michael Kors, Coach and so on. Employees have to understand that people are spending a lot of money in these stores so they always want a custom experience.

Child Minders

A great feature of many cruise ships is that there are child minding services offered in the form of child adventure centers. There are day camps available for kids so that they are occupied by responsible professionals, and parents can enjoy an afternoon by the pool with a drink without worrying about children running around that they have to mind.

Keeping a cruise ship running is a tough job and there’s a lot of moving parts to ensure all staff are doing the job they need to do. Every role plays its own part in the bigger picture, and each one is very important. For example, if child minding wasn’t available then parents might not book in to have a massage and therefore those services wouldn’t be needed. These roles all rely on each other to keep all passengers happy.

Food Prep on a Cruise Ship

Cruise ships take one thousands of passengers, and crew members, every time it sets sail on a new voyage. Depending on where you’re cruising to you might not see, or touch, solid land for a few days. A cruise ship needs to store and prepare food for thousands of guests for multiple meals and snacks every day. Many have wondered how it is that cruise lines manage to feed all these people, prepare the food, store the food and be able to offer so many options so that there truly is something for everyone.

There’s A Lot of People Involved

On a cruise ship at any given time, there are over a hundred – sometimes over two hundred – people working in the numerous kitchens aboard. There are multiple restaurants with a large variety of food offered, every single day, to all passengers. It takes all of these people to take over two hundred pallets of food and turn them into the delicious food cruise ships are famous for.

Team Work is Vital

Normally ships will start the loading process around 6 or 7 in the morning on the day the cruise sails. Kitchen crews have to work together to make sure the food is moved onto the ship in good time and is put in the right place. Some cruise lines switch the food from the standard wooden pallets to metal trays mostly because the metal trays are easier to clean, which means cross contamination is easier to avoid. Each pallet is checked over before it’s loaded onto the ship: the crew doesn’t want to take on a whole shipment of rotten produce, so they have to make sure it is good and will remain ripe but not rotten for the duration of the trip. If something doesn’t look right, it will be sent back to the supplier before sailing.

It’s All About the Storage

Once it’s been loaded on the ship, it will be transported to the right storage compartment. The storage, preparation and cooking are done in separate areas so to avoid cross contamination where possible. For example, on many ships there are kitchens specifically for preparation – like chopping tomatoes or cubing fruit for a breakfast buffet. This way the areas where meat is prepared and cooked doesn’t come into contact with foods consumed raw.

It’s Also About the Patterns

Some cruise lines have cameras posted in eating areas that do head counts. The crew members will use the recorded information to determine peak times, what passengers are likely to eat when and times they need to be prepared for. This also helps the cruise line chefs to be able to ensure they prepare enough of the most popular foods so that guests aren’t waiting at the busiest times.

The Ship Docks . . . Eventually

Occasionally a ship will run out of an ingredient; usually one that isn’t too popular so the crew may not have stocked much of it. When this happens, the crew will go ashore the next time the ship docks and will search the markets on those locations to see what they can find in terms of the food they are out of.

Feeding thousands of guests for a week, or more, at a time is definitely a large undertaking. Which is why most cruise ships have teams of people dedicated to the loading, storing and preparation of food on the ship. Kitchens can be found on pretty much every level of the ship and each will be making something wonderful for guests to enjoy. It takes a lot of planning to figure out to satisfy the stomachs of that many people with different tastes in food, but cruises are famous for their food options so they must be doing something right.

How Does Plumbing Work on a Cruise Ship

When you’re on vacation you might not be thinking about where the water goes once you flush the toilet or rinse something down the drain. However you’re in the middle of the ocean and there isn’t a sewage system to hook up to when sailing along, so where does it go and how does it work? Well, here’s an explanation as to what happens to sewage on a cruise ship. 

The Fresh Water Basics

Cruise ships use salt water for the water consumed by guests, however it isn’t just sea water out of the ocean. Previously, cruises would just use salt water but this lead to premature corrosion of the pipes. Currently ships will use desalination equipment: water is pulled from the ocean, run through the process and then transported to holding tanks. Some ships hold up to 2 million litres of fresh water at any time.

The desalination process will remove impurities and harmful minerals from the water, but adds in the important minerals found in drinking water. The water stored in these tanks will then be available for transportation to guest rooms, kitchens and where ever else it is needed on the ship.

The Sewage Basics

On every cruise ship there are two kinds of sewage: gray water and black water. Each one is whisked away from rooms into tanks called Gray Water Tank and Black Water Tank. Gray water is waste that goes down the drain (either a sink or a shower) and black water is waste that flushes down a toilet.

These tanks are typically stored away from the eyes of guests, but due to the number of people on a cruise ship they usually fill up quickly. When it’s time the water will be treated (as per regulations) and then will be dumped into the ocean while the ship is sailing.

There are specific regulations for dumping sewage, especially if the ship is within a certain distance from port but when the ship is out at sea the regulations are much more relaxed and it’s up to the cruise line to regulate.

Backups

Just like in your home, backups happen. On a cruise though, it’s a much bigger deal. People are stuck in small, confined spaces and being without running water is a big deal. Blockages in the pipes on a cruise ship are a huge deal: people are paying to be on vacation and a backup causing no running water will always be memorable. Cruises will have a plumber on board in case they need an emergency plumbing and to make sure everything is running smoothly.

Plumbing on a cruise ship can be a logistical nightmare because, should there be a problem, people are stuck without water on a vacation they potentially paid a lot for and they are on a ship in the middle of an ocean. Fixing a plumbing problem on a cruise is important, and it’s critical it is done quickly. Modern day cruise lines employ a fantastic system for bringing in and removing water and waste, with leading edge environmental engineering technologies.