I occurred to me after reading this recent Cecil article that some of the most famous maritime disasters could have been avoided if ships had hulls capable of withstanding ice impacts.
The first thing I thought of was cost. Why would a shipping company make their hulls extra resistant to impact if they don’t have to? Well, why isn’t such a thing simply a cost doing business on the high seas? Cars have airbags even though most of them will never be in an accident, ships have lifeboats even though most of them will never need them, planes have airbags for waterlandings and some parachutes even though most planes don’t crash, most of us have insurance for a variety of things that will never happen to us and a fire extinguisher for that non-existent fire that will never happen to our homes or office buildings. It seems like all ships should be required to have iceberg-proof and rock-proof hulls by design. Think of it as insurance, if the boat crashes and sinks, that’s probably going to be more expensive than getting a new boat and paying off the survivors.
If not, it certainly should be
Ice bergs are only a threat to ships on certain routes. Most ships will never encounter them.
That’s the answer to almost every “why don’t they…” question. There’s always a cost/benefit analysis. The costs of reinforcing hulls, together with increased fuel costs, don’t justify the minimal risk.
All cars are mandated to have airbags and other safety features because we don’t know which ones will be in a crash.
We know with absolute certainty which ships will be sent out to break paths through pack ice (because we choose the ship for the task). Note that icebreaking is not at all the same thing as colliding at full speed with an iceberg, which is, I assume, what you’re trying to deal with. Further note that there are already reliable methods (e.g. radar) for avoiding unexpected collisions with icebergs.
Also, airbags and other safety features add a relatively modest cost to the purchase price of a car, whereas designing/building a ship to be an icebreaker adds a rather hefty cost to the purchase price, as well as increased operating costs.
If I’ve got a ship that’s only ever going to sail between Hong Kong and the Port of Los Angeles, icebreaking capability would be a colossal waste of money.
Well, not only icebergs, but rocks. Of course I was thinking about the Titanic when I wrote this, but that seems like it would be a perfect counterargument. It was a cruise ship designed to have rich people sail around the world in, but in this case, their course went through someplace cold and they struck an iceberg and sank. I can imagine those big cruise ships that go up to Alaska having the same fate, so they seem like they should be all impact resistant.
But more than ice, there are rocks. Any cruise ships that docks on some sunny vacation spot in parts of the world may run into rocks. Seems it would only be fitting that they have reinforced hulls
Sonar and good charts are much cheaper than reinforced hulls and will avoid almost all risk of collision with rocks, at least in good weather. Despite all the publicity about the Costa Concordia, cruise ship collisions with rocks are very rare and that one was due to human error.
Icebreakers don’t just have extra-strong hulls. The hull shape is designed to push down on the ice to break it. And because the hull shape is designed for this, rather than being optimized for low resistance, I would assume they are less fuel-efficient than conventional ships.
Ask yourself this…how many ships are sunk yearly because of icebergs? Looks to me like that number is pretty small (vanishingly small in fact), so you are trying to solve a problem (by having all ships be ‘icebreakers’) that isn’t actually a problem. And the ‘solution’ is going to cost a lot of money for very little, or no, gain. And that’s the answer.
The Titanic wasn’t a cruise ship: it was a passenger liner intended to carry passengers between England and the US. In those days, the only way to cross the Atlantic was by ship, so it wasn’t only rich people going that way. In addition, travelling from Southampton to New York City (as the Titanic did) on a great circle route would take you through an area where you would expect an occasional iceberg.
Keep in mind, an icebreaker is not just designed to survive an impact with ice. It’s purpose is to break ice. Every aspect of its design is devoted to this purpose.
So to return to the car example, the car has significant safety features to protect the passenger in the event of an accidental collision. This is very different from something like a bulldozer, which is designed for* deliberate* collisions.
Furthermore, many of the features on your car are intended to protect the passenger while sacrificing the car. Several decades back, cars were built to be much more solid and robust than they are now. We found out the hard war that this was the wrong strategy.
What would happen if an icebreaker collided with an iceberg anyways? As I understand, they usually deal with a flat layer of ice on the surface of the water, not a big chunk of it sticking out higher than the ship. Something tells me the icebreaker would still end up the worse for wear after such a collision.
On that note, how often do ships run aground, especially since the development of sonar and radar? Do note that even if ships don’t carry such sensors aboard, these technologies still allow for the creation of far more accurate charts which can then be distributed to other ships.
I actually had occasion to learn about this recently. The Coast Guard wants a new icebreaker that will displace around 12,000 tons and cost about $1 billion.
Looking at the Wikipedia page for Maersk Triple E class container ships, they displace 55,000 tons and cost under $200 million.
Ships do run aground these days. Silt and mud have a way of collecting on the beds in their own manner, tides have a way of rising and falling, and charts have a way of not being updated weekly. Often a grounding is resolved by waiting for the water to rise.
Icebreakers are NOT armored to resist punctures anymore than any other ship. Yes, the bow may be beefed up. Non-breaker hulls are pointy in front to cut through the water. Breakers have hulls that are shaped like footballs in front. They ride up on the ice sheet until their weight crushes it. And breakers have ballast tanks to adjust the pitch and gain weight as desired also.
We should just make ships out of the same apparently nearly indestructable material that Tony Stark uses in his ‘Iron Man’ suits. While we’re at it, we can power them with ARC fusion technology and use his ‘proprietary thruster technology’ to enable them for continuous suborbital flight, thus avoiding the entire problem of icebergs and rocks all together.
Next up, we’ll cure all trauma and illness just by synthesizing the Super Soldier formula used on Steve Rogers, and then expose patients to Vita-rays to energize their transformation.
Now if only we could do something with interdimensional travel…
Icebreakers can’t break icebergs. Even if they could, someone would first have to see the iceberg and configure the ship for breaking. And if you can see the iceberg… well, just go around it.
Icebreakers are for cutting a path through vast sheets of ice, not for destroying anything they come into contact with.
So you have a fully loaded bulker with a total displacement of up to several hundred thousand tonnes, and it hits a rock at 13 knots (about 15mph/25kmh) and the hull is going to withstand that without tearing. I could probably fudge some sort of answer as to how much pressure that is likely to create and what it would take to withstand that, but there are engineers on here who could do it quicker.
Suffice to say the hull would need to be a quite extraordinary engineering feat, likely so heavy as reduce carrying capacity drastically. The forces involved are almost unimaginable.
Sonar range is far less than the distance it takes to stop or turn a large vessel.
Sofas aren’t necessarily that heavy. Me and a buddy were able to move both of my sofas easily enough. I’m not sure a body builder would be able to one man lift a full-sized sofa in a way that would allow him to finesse it through a doorway.
