Is sustainable passenger traffic across the Atlantic possible?

Question

The current preferred means of travel from New York to London or Paris is the jet plane. Which is a shame, because:

1. It is poorly designed. The fact that "it is the best we can do" is no excuse. It's not a proper means of transportation: it's a flying gas tank. Literally. There's fuel in the damn wings, even. Most of the energy the burning of this fuel generates is spent on carrying the plane itself, and its fuel. It is said that a car (another lousy design) expends about 99% of its energy on carrying itself, and about 1% on carrying the passenger. I don't know if the jet airplane is better or worse, but surely it's in the same category of moronic guzzlers. Note that the design of the jet has not changed significantly in fifty years. This is, like, I don't know, medieval.

2. To keep the airline industry afloat, so to speak, thousands upon thousands of planes need to take off every day and travel at speeds that increase their fuel consumption by something like 50%. In order to do this, millions of people are coaxed, coerced, or bribed into traveling to destinations they have no particular desire to visit, or, in fact, into traveling at all. Do you have to attend that conference? We do have videophones, you know. However, the airlines contend that a decrease in volume would drive them all bankrupt, and commercial aviation would promptly cease to exist. This is true to some extent - with the fleet they have today.

I have seen tourists in Times Square "taking pictures" of computerized billboards. I have seen tourists under the Arc of Triumph in Paris "taking pictures" of each other against the background of the memorial fire. It is not obvious to me that they need to be there. The one thing that would get them to curb their tourist appetites would be a sharp decrease in their comfort level.

Thus my question is: air or water? Should engineers bend their energies on improving air travel or sea travel?

Those fabled clippers, they could cross the ocean in about twelve days. Each time it was a very uncomfortable trip, replete with danger. Could it be made more comfortable with today's technologies and know-how?

Or should we take a closer look at airships and see where that leads us?

Answer 1

Air or water? Should engineers bend their energies on improving air travel or sea travel?

Air. Regardless of sustainability, people who are used to hypermobility will not easily accept that mobility to be taken away.

There is work going on on electric aircraft. Current batteries have insufficient energy density, but energy density is increasing rapidly. I don't know if we are anywhere near theoretical limits — you might ask here or on another Stack. Wikipedia quotes Elon Musk saying once batteries are capable of producing 400 Watt-hours per kilogram, with a Power-to-weight ratio of between 0.7-0.8, then an electrical transcontinental aircraft becomes “compelling”

Which then reduces the aviation question to an electricity production question. We already know how to do that sustainably. Then there is the full life cycle of the batteries itself, which has non-zero impact.

Is a transatlantic voyage across the Atlantic possible with absolutely zero impact? No.

Is a transatlantic voyage across the Atlantic (in less than 12 hours) theoretically possible with impact that is orders of magnitude lower than now? Currently, no. In the future, perhaps.

^{(I wonder how long an aircraft could fly powered by an RTG.)}