If I asked you to think of the biggest ship in the world, what pops into your head? Maybe one of those super fancy cruise ships with a roller coaster on deck? Or maybe you're thinking of an aircraft carrier loaded with high-tech military planes sailing across the ocean?
Well, surprise! Neither of those are actually the biggest. In fact, the largest ship ever built isn’t even around anymore! And no, it's not the Titanic either. Believe it or not, the construction of the biggest ship ever started about 50 years ago.
In 1974, a Japanese company named Sumitomo Heavy Industries was called upon to start construction on the largest moving structure ever made by human hands. It was a supertanker called the Seawise Giant. It must have been discouraging for the builders when the original buyer bailed out. Luckily, a shipping container company owner from Hong Kong purchased the Giant a few years after its completion.
The world's biggest ship was designed to haul cargo and oil across the ocean. It wasn't the most practical vessel, though, as it took almost a 2 mile radius to make a turn. You were in trouble if you got in its way, too, as it needed nearly 5 1/2 miles to make a complete stop! The ship would sit in the water 81 feet deep - known as its "draft" - when it was fully loaded. The Seawise Giant was so big, it couldn't steer through the English Channel!
The Seawise Giant had a tumultuous career. It was blown up off the coast of Iraq when the Gulf War started heating up. It sank to the bottom of the Persian Gulf, but it was raised, repaired, and changed owners to continue hauling goods across the world's oceans. It was renamed several times, too. In its last days, the Giant was parked at a port in Qatar holding oil before it was transported to India to be torn down for for scrap.
While its size was impressive, the Giant was simply too large to be efficient. It burned up huge amounts of fossil fuels to move and maneuverability was a challenge. That's probably why no one has attempted to build a new vessel matching the dimensions of the old Seawise Giant.
How big was the world's biggest ship compared to other things we might know? The width wasn't very impressive. The vessel was just 225 feet wide, which is the same as the wingspan of a 747 jumbo jet. The deck of an aircraft carrier is actually wider than that.
The length of the Seawise Giant did set world records at the time. The ship was 1,504 feet in length - taller than the Empire State Building or the Eiffel Tower! 😱 No wonder the thing was so hard to steer!
There has been one longer vessel a little longer than the Seawise Giant - the Shell Prelude, a floating natural gas platform - but none have matched its ability to carry materials. It holds the record in "dead weight tonnage" - it could hold 564,763 tons total of people, fuel, and whatever it was transporting!
Here's a visual showing how the Giant stacked up to other lengthy objects:
Here are some questions I'd get my students thinking about if I shared this visual in class:
💡What is the height of the tallest object on this graph in meters? The tallest object is the Burj Khalifa building standing at 800 meters tall.
💡There are roughly 3.3 feet in every meter. About how many feet tall is the CN Tower? 500 meters X 3.3 = 1650 feet.
💡The average person runs at about 3 meters per second. Calculate how long it would take a person to run the full length of the Seawise Giant. The graph shows the Giant as being about 450 meters. 450 / 3 = 150 seconds or 2.5 minutes.
💡What are some challenges that the engineers might have considered when designing such a large ship? Some ideas could include: waves and wind could affect a big ship unevenly; the size of the engines required to move the ship (it traveled at 16.5 knots!); the communications across the ship; navigating the ship when the front is so far from the back; would the ship fit into most ports for loading and unloading?