How could ocean liners survive in a major capacity after large jet airliners become common? [closed]

Question

Ocean liners, distinct from cruise ships, largely died out in the 1960s and 1970s due to competition from the introduction of airliners such as the Boeing 707, 727 and 747 and the Airbus A300.

For the purposes of this question an ocean liner is defined as a large seagoing vessel, designed to go as fast as it can and withstand very bad weather conditions, intended for the transportation of passengers (possibly in combination with express freight and mail), with the main focus of the design being transportation above leisure. They are distinct from cruise ships which forego speed and ability to withstand rough weather for luxury and are designed for leisure above transportation.

Surviving in a major capacity means that someone could get between any two major oceanic port cities by ocean liner, even if they have to transfer between ships in between.

Large jet airliners cannot just be made to simply not exist. Ocean liners should coexist with them. Both should be accessible options for those with the money for international travel.

Ocean liners don't have to keep existing forever. If whatever the solution to make them coexist with jetliners ceases to work going into the 2000s that's ok, but they need to keep existing at least up until the late 90s.

Cruise ships do not count. I have already defined what an ocean liner is vs a cruise ship above. Do not just answer "Cruise ships exist".

Answer 1

More frequent and widespread volcanic activity.

This leads to common, widespread & often major disruptions in air travel (by jet). Nothing world-ending BTW there’s just many, many more low-level eruptions pumping volcanic ash into the sky that tends to make large scale jet travel less safe and not as reliable as it otherwise would be. This in turn sharply increases airline operating costs. Real-world example: Air travel disruption after the 2010 Eyjafjallajökull eruption.

The rich can still travel by air because they can afford to pay the airlines a premium covering the added costs these disruptions cause and the diversions that often result. (Or if they're rich enough? They can buy their own private jets.) The working classes? Travel by sea.

Answer 2

Ultimately you have three options:

• Natural: the conditions within the sky create less than ideal circumstances to fly. Turbulence is a near-persistent problem. People are afraid enough to fly with the relatively low danger threshold we already have.
• Economic: working alongside the natural is the financial burden that this system would pose. Ocean liners would be much cheaper as you could transport far more in less than ideal conditions with the only downside being speed of travel. Similar to universes where the Hindenburg didn't happen, the cheaper alternative of blimps became the de facto form of transportation
• Psychological: people could just decide that they don't want to use jets. There is a safety and security in Ocean Liners. That or emergent culture forced it in that direction.

Answer 3

NIMBYism

The thing about airplanes, they need airports. Airports have everything that nobody wants to have as a neighbor:

Toxic chemicals? We've got jet fuel, tetraethyl lead in the avgas, de-icing agents, plus lubricants and hydrolic fluids galore. Check.

Noise? Jet aircraft are literally the exemplar of damaging levels of sound.

Traffic? A nightmare.

To make matters worse, the very existence of an airport forces physical limits to what all neighboring plots of land are allowed to build, in order to clear the airway for planes to fly with sufficient separation minima.

Seaports have a lot of the same issues, sure - but the noise is profoundly reduced (ships don't go blasting overhead my house... at least not until climate change has had a few more centuries to work) for individuals, and the majority of neighboring real estate is the ocean... which nobody's building on anyway.

Unless you're in a spectacular hurry, sea travel is friendlier.

Environmental performance

Remember what I said about Tetraethyl lead? Before turbines, it's piston-driven props running on leaded gasoline. This is NOT optional. We still use it today because nothing else* has been proven to effectively get Octane levels up above 100. 100+ Octane is NOT optional for aircraft - ultra high compression is THE key to aircraft engine power.

The only other way to get that kind of Octane rating is with ethanol, but ethanol is aggressively volatile it gleefully boils away as you climb, creating a condition known to engineers as "vapor lock" - and known to the rest of us an "engine failure emergency."

(* There's one promising candidate in the market now, but it's struggling to get adopted.)

If people want to get lead out of gasoline, including aviation fuel, this limits the power available to aircraft and prevents airline infrastructure from being developed anywhere near as robustly. Seat prices go way up, and aircraft must fly lower - meaning less efficiently.

I know you said speed over comfort but...

Comfort is relative. An ocean liner enjoys tremendous economies of scale, and so may include all sorts of amenities that even modern long-haul airliners can only dream of. Compared to one of those noisy, filthy, cramped airplanes? It might as well be a cruise ship. Maybe we're not taking in concerts, gambling, or stopping at every tropical port with a tourist trap... but I can at least breathe fresh air, walk around, stretch my legs, eat at a proper table like a civilized person - and at a fraction the per-seat price. I can also bring whatever luggage I please, and I didn't have to go WAY out into the boonies to get to that utterly remote airport nobody would let be built near them.

Air travel, to abuse a quote, ends up 'nasty, brutish, but short.' It's reserved for military/emergency purposes only - or the eccentric but spectacularly wealthy. High-speed rail replaces the ocean liner inland, but air travel across large spans of LAND is more common than trying to fly the things over the oceans.

Answer 4

Environmental awareness.

People consider airplanes (and cars) a source of pollution. All ships have nuclear reactors and do not generate even a fraction of the pollution of passenger planes. They have very good public transport and electric cars for local transport.

Airports are the subject of protests due to noise and other pollution, only their use by the military is accepted, but the military is located in places far from large cities

All power plants are nuclear, the fossil fuel ones were replaced in the early 50s.

Answer 5

Smaller distances and no ground based alternatives

The issue with transoceanic travel is that even on the record breaking ships, crossing the Atlantic takes a good part of the week. So even completely neglecting the costs for actual transport, just the cost for board and lodging, as well as the lost time make the plane a favorable option.

However if you look at shorter distances, there is still a surprising number of sea-going ferries operating in the world, even in Europe where people can afford flying, from short trips like across the English channel to longer overnight routes, like crossing the Baltic sea or between Mediterranean islands. Using them for personal travel is getting less common as flying gets cheaper and cheaper, but I would claim that given your timeframe at least in the late 90s for a lot of Europeans, the annual holiday trip involved taking a ferry at some point.

Then why is there no dense network of such shorter routes linking all the worlds ports? The issue is that you have identified the plane as one competitor, but on those shorter distances, the main competitors are cars and trains. Taking a boat along the coast is never a good option, if there is a good enough parallel road or train track.

So remove that option. Turn your world into an archipelago. If European geography looked more like that of Indonesia, there would probably be almost as many people taking the boat as take long distance trains now.

Answer 6

Economic Reasons or Catastrophies (mainly)

There are so many aspects that can be tweaked to make that happen. Here are a few ideas on a macroscopic level:

• Fatal accidents (like the Hindenburg or the Titanic) might account for the people favoring the one or the other.

• Technological advancements (like better propulsion for either ships or aircrafts) can make the or the other more attractive.

• Economy / Financial situation of the people or the world market in general can make one of the two more affordable than the other.

• Heavy Freight that is most lucrative, might be needed in large quantities around the globe, but it is much heavier (like ore for example), so airplanes are not an option.

• Law forbids/regulates the excessive use of one or the other.

• Fuel is scarce maybe, producing more kerosene is not possible, but burning crude oil on ships is easier. Can be combined with a global oil crisis and destabilized financial markets.

• Cartels have monopolized airlines and ships. They make arrangements concerning availability and pricing among themselves to maximize profits. Leveling out the use of both. Cartel could be legally or illegally acting, depending of the intended setting.

• Global catastrophies may account for climate conditions and sea ways to change. Rising sea levels could make using a ship much more effective. While for example a large amount of volcanic ash in the air, decreases the effective use of airplanes. Or high levels of radiation are unhealthy for the people in airplanes. Therefore they need heavy lead shielding, which make them cost intensive.

• Population changes either increasing or decreasing can account for the higher need for transportation (therefore more ships and more planes). Or lowering the population (or at least the travelling amount of people) can level out on a fairly equal but low usage rate for both types of transportation.

• Alternate-Timeline like WWI/II did not happen, black friday did not happen, cold war did not happen, oil crisises did not happen, ... The increased overall "happiness" and positivity lead to many advancements in technology of which the whole world benefited from. Airplanes and ships are both commonly used and highly advanced in tech-level.

• Political tension lead to more conflicts. The continents were eventually politically more isolated. Some of them favor the use of airplanes, others (coastal regions) the use of ships. Some countries declared no-fly zones, making travelling by air difficult. Ships are an option, but they also rarely take routes to other continents. On average ships and planes are used roughly the same amount, though.

Answer 7

Jet Engines Became a Regulated Military Technology

Compared to airliners, ocean liners are a crude and inefficient technology for transporting people, being several orders of magnitude slower. This inefficiency translates into higher costs for a single trip. Passengers need to be provided with meals and quarters for a journey that typically lasts several days, which increases the crew-to-passenger ratio compared to airliners. However, it wasn't until the invention of the jet engine that ocean liners truly became obsolete. Jet engines allowed airliners to travel faster and farther with less turbulence and better fuel efficiency.

To preserve the viability of ocean liners, the rise of the jet airliner must be prevented allowing ocean liners to continue to coexist with airliners used for intranational flights. An effective way to delay this technology would be for the US military to classify jet engines as a controlled military technology, similar to nuclear technologies or advanced encryption. The 1950s, during the height of the Cold War, presents a strategic context in which the US might plausibly restrict the spread and export of jet engine technology.

Assuming this ban on consumer use continued until the end of the Cold War, the rise of the jet airliner could be delayed until around 1995. This would allow ocean liners to remain a significant mode of transportation well into the 2010s and possibly the 2020s. If you wanted to extend this further, public distrust of the newly developed jet airliners following the 9/11 terrorist attacks (assuming they still occur in this timeline) could further delay their adoption. Alternatively, the extra fifty years of development could allow ocean liners to enhance their speed and economic efficiency, outstripping early jet airliners and delaying their widespread adoption.

Impacts on World Development

Slower global travel would have significant impacts on economic activities. The shipping of perishables and just-in-time manufacturing might not develop in the same ways as in our timeline. Ocean liners, with their longer travel times, would necessitate more durable goods and different logistics strategies.

Ports would become even more economically important as primary centers for international travel and trade. Coastal cities with major ports would likely see greater growth and development, becoming hubs of economic activity and cultural exchange.

Tourism would be significantly affected by longer travel times. International vacations would become less frequent and likely longer to justify the extended travel duration. This could lead to a focus on high-quality, extended vacation experiences rather than short, frequent trips.

The slower pace of travel would impact the projection of political and military soft power. Diplomatic missions, cultural exchanges, and the deployment of military resources would take longer, potentially altering international relations and the speed of response to global events.

Answer 8

Economics

You can make travelling by sea cheaper by:

• Making coal super cheap, almost free: A coal powerplant or steam engine easily can be made to fit onto a large ship, they would benefit from inexpensive propulsion (which is most of what you pay for when travelling, so the price would be very low). Planes would not benefit from this. This would also work for other energy storage or power generation solutions that require lots of space or are very heavy. If you have cheap and plentiful nuclear-powered civilian ships that could also work.
• Add a passenger section to the already-existing cargo ships: The ships already have crew areas, make them bigger with better finishes and increase revenue per crossing. Or, another way to use cargo ships:
• Ship yourself and your family in a shipping container tiny home: image source If you allow people to ship themselves and family members or friends (up to 5 people per container) in modified containers such as the one below, it becomes very cheap per person to cross. No modification needed to the ships.

Lastly

• Government subsidies: Greenhouse gas emissions are a big concern nowadays, and it's no secret that travelling by air emits much more CO2 per mile than travelling by sea for a given load. Governments could have agreements that for travel between their two countries they would each pitch in to subsidize sea liner tickets and incentivize people to travel by sea.

Answer 9

Religious reasons

Everything else I could think of has already been answered, but I haven't seen this one yet.

There are millions of people who won't eat pig meat because their religion forbids it. Other millions of people won't eat cow meat for the same reason (but a different religion). And another other millions of people only eat meat if it has been killed by bleeding out.

If a religion of relevant size in your world preaches that flying means to intrude in god's realm (the skies are closer to heaven, or something), there will be millions of people who will take ships every time they have to cross an ocean. Easily enough to keep an industry alive.

Answer 10

I have a radical idea, other than making airlines expensive and unsafe. You need a big population of people living in campers/mobile houses that want to travel around the world.

If you live in something like this then travelling by liner makes far more sense than by airplane.

• You won't need to pay for accommodation while you wait for your house if you travel by airliner
• Liner is cheap because you already pay for the transportation of your house.

You need some good reason for that population to exist but this should work.

Answer 11

A slight cultural shift toward comfort. See Amtrak

Who rides Amtrak/VIA? People who'd rather enjoy a 3 day land cruise than suffer the humiliation of taking off their shoes, being herded like cattle, and crammed into tiny seats with no idea where to put their elbows for 5 hours, although it's really more of a 10 hour ordeal portal-portal.

It's misery, but "we all" put up with it as sort of a shared social pact/agreement. What if we didn't? What if 5% of travelers said "nope"?

That's it. Amtrak and VIA's long haul runs are almost profitable despite heinously bad timekeeping and desperate equipment shortages. Cruises are already hugely popular. So you simply get the "can't stand the dismal flying experience" 5% to simply say "I'd like to bookend my European vacation with short 3 day cruises". That's it. You’ve won.

At that point, cruise ship economics take over, and that's well-understood. Even the "cheap seats" are a wonderful experience compared to flying. Of course some are mobbed into mediocrity, but there are tiers of cruise experiences that go as high as you want, to Cunard and beyond.

Speed and rationale for subsidy

Now a word on speed. If we're really doing ocean liners, we're going to build more SS United States except with gas turbines instead of steam turbines. These things will clip at 35+ knots and do 3-day crossings, and be stealing the Blue Riband from each other on a regular basis.

We are not very far from that, we just need the same kick that Amtrak and VIA gets: subsidy so it can be assured of surviving hard times. And the government rationale to do that is defense.

The "defense" argument would be helped if military science was really good at slipping out into the ocean with long-distance patrol aircraft and shooting down airplanes to where one would struggle to sustain an air bridge across the Atlantic or Pacific. But not so good at sinking well-defended ships with destroyer escort, or onboard CIWS. At that point, the government would subsidize the liners merely for troopship use in wartime.

Answer 12

In the real world, ocean liners died out once jet travel became comparable in cost to jet travel. They didn't just die out in the 60's If you want ocean liners to co-exist a few options include:

jet fuel is more expensive while ocean liners can use cheap coal.

Some part of the jet engine requires materials that are more expensive than on our universe (inconel / titanium etc)

Perhaps nuclear reactors to propel ocean liners are available with minimal running costs.

Light weight aluminum required to build jet aircraft is expensive.

You simply need to keep the economics so that Liner travel is accessible to more people than jet travel

Answer 13

Fashion

Put simply, ocean liners are seen as being fashionable in some quarters. The plane might "not be for our type of people".

Maybe people from lower income background see planes as being rich man's toys and want no part of them, or maybe the middle classes see planes as being uncivilized because (and this is true) the early long distance passenger aircraft were often converted bombers. Or at least based on WWII bomber technology.

Pure social reasons of popular opinion could keep ocean liners going.

Answer 14

Radiation

The Earth's magnetic field is going through one of its reversal events. This means it isn't just flights at very high latitudes that have to be re-routed to avoid the hole in the Earth's magnetic screen at the magnetic pole, and the state of play changes on a weekly basis. Simultaneous with this (or possibly linked?) the sun has become unexpectedly active. Big solar storms are now to be expected more frequently.

The combination of the two means that travel at 40,000 ft for a few hours involves a significant radiation dose. Not anything immediately life-threatening, but the sort of dose you accept in a medical setting only if there is no good alternative. Also, of course, radiation doses are cumulative. Frequent flyers need to wear dosimeters, and may be grounded.

Apart from health concerns, maybe exaggerated, air travel has become less reliably fast, because of flights frequently getting cancelled or re-routed. Also the cost has gone up and the standard of service has gone down. Cabin crew is no longer a permanent job. It's a job one is allowed to do for a month, before being grounded for several months by exceeding the maximum legal radiation dose. Flight crew likewise, meaning there is a desperate commercial pilot shortage (and suddenly, 747s and 380s are the planes to have! )

If you are not in a serious hurry, the low radiation dose, luxury and reliability of a boat is to be preferred.

Answer 15

Nationalism, Isolationism, and Xenophobia:

Air power is seen in a strictly military way. Early development of flight technology was for strictly military applications, and the technology is seen as a military secret. Further, biological, chemical and radiological weapons were not developed until after the advent of aircraft.

The first "commercial" airline was a ruse by one government to fly long-range aircraft filled with anthrax deep into the territory of a neighbor for a massive surprise attack on military and civilian targets in a huge Pearl Harbor-style attack. The one world war that was fought was a horrific affair with the long-range use of kamikaze dirty bombs, disease, fire bombing and nerve gas. The idea of foreign aircraft in a nation's skies is terrifying to both generals and the civilian population. Today, all air travel is controlled by the national military defense systems. There is no civilian air traffic control network.

Meanwhile, the governments of the world are heavily invested or have nationalized the ocean liner industry for pride and military preparedness. Competition for the fastest liner never ended, and states advance the technology for catamarans, air cushion vehicles and ground-effect vehicles.

While the horrors of the Great War have faded, it has left a scar on the psyche of the world. Airlines operate almost exclusively within the territorial boundaries of states. The travel of foreign nationals is tightly controlled, and they may only legally arrive in port cities (so even airlines must land at national borders).

SO:

Airlines operate behind the times technologically in an environment of fear and suspicion. They rarely cross national boundaries (and thus, usually oceans). Water transport is advancing technologically faster and faster with subsidies from powerful militaries. Fear of aircraft poisons the minds of the common people, and fear of Trojan nukes grips the imagination of military planners.

Answer 16

Nuclear Vessels

What do you do when you have an oil crisis on your hands and worries about peak oil dominate the discourse? You go for an alternative source of fuel.

They tried to put a nuclear reactor on a plane and failed. On the other hand, nuclear-powered ships are relatively straightforward and existed as early as 1955, with civilian designs operating in the 60s.

While planes have to be refueled every flight (and during the 20th century, sometimes multiple times for long-distance flights) nuclear ships can go several years without refueling. This is really useful if you want to go between places where refueling is too difficult or not commercially viable.

Answer 17

The Titanic never sank, But the Phoenix fell from the sky.

Historic events and how they are perceived in the public eye can influence trends drastically. We all know the Hindenburg disaster.

In your world, there was an event or series of events (An exceptionally bad airplane crash, "the Phoenix") that retarded the development of the airline industry. Also events that would cast a shadow on ocean travel (The Titanic among others) didn't happen. Leaving the only other alternative the ocean liner. Of course many other answers here can and probably should be integrated to reinforce the idea, Such as technological and economic reasons. But the impulse driving society toward ocean liners is basically bad luck in the air and those in a position sailing the seas took advantage.

Not only by public opinion, but the energy behind all facets of development, scientific economic and otherwise, can be accelerated or extinguished by the perception of the populace at large.

Answer 18

State intervention. Be it subsidies, economic planning, etc. Not only that, but ocean liners can carry more for cheaper (they just move slower) so cargo prices will be much cheaper then airliners.

Answer 19

Pandemic Quarantine

Some people may remember that COVID-19 disrupted world travel massively in the recent past. Prior to the development of vaccines, many countries and regions imposed quarantine restrictions on new arrivals, requiring them to stay in designated accommodation for a period after arrival.

Let's assume that COVID-19 was actually COVID-59 instead being detected at the end of 1959. Oceanic liners were being superseded by air travel already but most of the vessels still existed. Vaccine development and testing technology was vastly more primitive. It would be reasonable for at least some nations to encourage sea travel that could double as a quarantine period, rather than flying them at high speed and then quarantining them in onshore accommodation which some of them - based on real-world experience in 2020-21 - would break out of.

So, until the COVID-59 threat can be dealt with, countries such as Australia, New Zealand, Indonesia etc basically mandate that all arrivals must travel on government approved ships, with time-consuming, primitive (1960-1990) testing conducted over the course of the last few days of the journey. Given the technology level, it could be reasonable to expect that vaccines could take decades to develop. Until vaccines or mutation make COVID-59 less of a threat air travel can still exist, whether it is used only by rich people with luxurious quarantine facilities to stay in on arrival or by everyone in regions misgoverned by idiots with no understanding of health science.

Answer 20

How much does your world need to match Earth?

Because there's a simple change that kills long range jet traffic: Raise the air pressure. Drag goes way up. In theory you can fly high enough to get good performance but you end up hauling enough pressure vessel up enough altitude for jets to never really catch on.

Answer 21

Two small changes in history could make this happen.

In our world, passenger liners had an extremely rough time through the world wars. Many were outright sunk, and many were taken by governments and re-purposed as troop transports or hospital ships. Few remained after the war, and ship operators would have to re-build their fleets before passenger traffic could return to normal levels. This was prohibitively expensive in terms of money, resources, and time, so the ocean liner industry never really recovered. If operators could have emerged from WWII with most of their fleet still operational, then passenger traffic could resume almost immediately and operators would have an income stream they could use to rebuild. Airplanes would still exist, but the ocean liner industry would no longer be weak and easy to supplant.

The second change would be for ocean liners to become a bit like RVs are for us. They're definitely not for everyone, but they've attracted a very loyal customer base. There are still plenty of people taking airplanes, but the ocean liner crowd remains large enough to keep the industry afloat (har) for several more decades. It would be a gradual decline instead of a sudden disappearance.

The ships themselves would likely evolve into hybrid cargo/passenger ships. As airplanes start taking more and more customers away from ships, the ships reconfigure more and more of their passenger space into cargo storage. At some point ridership will cross a threshold where economies of scale start working against you. You no longer have enough passengers on a given ship to cover the costs of foodservice, cleaning, maintenance, entertainment, etc. and the passenger section of your ship becomes impossible to operate profitably. Amenities start disappearing, leading to fewer passengers, and the self-reinforcing downward spiral eventually ends the passenger liner industry. The few that remain are converted into luxury accommodations for wealthy people and VIPs who are willing to pay extremely high prices to travel in style, isolated away from all those commoners on airplanes.

Answer 22

"Fuel is scarce" is another reason to try advanced ocean liners. These ones powered by either solar energy, wind energy or both. Modern sails are being developed even to this day. A clever design can employ the two energy sources on the same ship. This is a cruise ship. However, an ocean liner is meant mostly for cargo can be covered with more photovoltaic cells, even at the expense of fewer windows. They are enclosed (like the one here) to improve aerodynamics as well. The design still has to get around the problem of how does the ship load/unload its cargo (What are the costs of a folding dome? or maybe cargo is moved through the rear end of the ship?). Despite the extra complexity, applying the same technology on airplanes is not that straightforward.

Another reason is transporting large amounts of volatile/flammable/toxic materials. It is much easier to transport oil with oil tankers, not airplanes. Some materials like pressurized canisters, batteries, acids/bases and mercury have strict regulations pertaining to transportation by air.

Answer 23

At least one major seaport city is situated near a hostile warzone. It is not accessible by rail and it is not safe to fly there since all airports are bombed occassionally. There are a few ocean liners routes which connect it to nearest overseas ports, which happen to be, on average, one thousand kms away.

Think Hong Kong, but with an actively hostile China and no Taiwan.

Case of point: Due to the Russo-Ukrainian war, major megapolises such as Rostov-on-Don and Krasnodar on the Russian side, as well as all of Ukraine, are civilian no-fly zones for a few years now. So the most reasonable mode of transportation is overnight sleeper trains in both cases. But what if they were coastal instead of inland?

Answer 24

Mass Migration

No one has yet mentioned why ocean liners really exist in the first place. Migration. The vast majority of passengers on Titanic were in steerage. Steerage is unpleasant and wasn't really seen as a viable option for "travel". Most of these folks were probably on a one way trip from the UK to the US where they planned to immigrate to. Many were poor, many were families. This was pretty much the case since ocean liners were first built.

After World War I, literal boatloads of people left Europe for America. Simply rinse and repeat for WWII. Perhaps prolonging the war a bit, perhaps follow through with Operation Unthinkable rather than the Marshall Plan. With Europe in ruins from Paris to Moscow, millions of people in destitution, they'll leave in droves. Perhaps to the US, perhaps Canada, Australia, Latin America. You won't be able to build ocean liners fast enough to transport all these people and their belongings.

I suspect that this scenario would delay commercial aviation, and with a more devastated Europe, there likely wouldn't be a sufficiently robust infrastructure to handle the efflux of people.

Eventually Europe might rebuild sufficiently that emigration will slow. As their economies pick up again, commercial aviation may become a more viable option. An then your ocean liners can fade away until they're next needed...