For example, people going to the Bahamas or crossing the Atlantic to visit family would respond to higher travel costs by going less frequently and staying longer. The net impact on time spent at the destination would be small.

For people who don’t have a strong desire for a particular destination, the implication, as you say, is to have your holidays closer and spend more when you get there. Again, the net impact on standards of living is modest.

Obviously, there are some particular social strutures that are impediments to this kind of adjustment, like short holidays in the US, discussed above. I’ll discuss in subsequent posts why this means we need to look at things other than prices. But prices will do most of the work.

Roughly speaking, for a given aircraft weight you need smaller wings the faster you fly, and this reduces drag just as much as the higher speed produces. So the drag associated with the fuselage is the only thing that goes up with speed.

On top of that, keeping an aircraft airborne produces a drag that actually rises when speed goes down (which is more or less why aircraft can’t hover). So decreasing speed can only go so far before drag goes up again. The optimum here depends more or less on weight, so it makes sense for small craft to fly slow, but not for big ones (birds fly even slower). In fact, current long-range airliners have weight-to-drag ratios unmatched by most slower aircraft.

The main reason aircraft might benefit from lower speeds is that currently a lot of aerodynamic trade-offs are needed to postpone and diminish speed-of-sound effects ( the MSc thesis I am working on is about this, for example :-) ). If we were to fly slower we would have more freedom to design a better aerodynamic shape.

Luckily, we have a beautiful example of the efficiency gains that could be achieved if someone spends all available design effort on a big plane with minimum drag without need for speed. The Global Hawk, a very large unmanned reconnaissance plane has a optimal weight-to-drag of 33 at a speed of 400 mph (presumably the optimum, sice the aircraft flies in circles), compared to optimum 19 for current airliners. It’s unlikely we could reproduce that 33 in an aircraft with a large fuselage and higher weight, but perhaps 25 or so might well be possible. That’s 20% gain from flying slower and redesigning.

It seems to me that lower income people would be prevented from flying at all, there would be a social stratum that would fly with reduced frequency as you suggest, and upper strata would be largely unaffected. Advantages of this would include overall reduced flight volume and the ejection of the hoi polloi from your comfy little tourist spot in the Bahamas, or Thailand or wherever. Also, I imagine, a radical reduction in tourism-related income for the Bahamians, concentration of services on the wealthy minority that is capable of frequent foreign travel, and the return of free champagne aboard for the reinstated privileged jet set.

I can see that something like a per-mile tax would change my own vacationing habits strongly: coming from a place with a relatively high median income and a strong currency, when I’m planning a vacation I find there’s often a trade-off between flight cost and food/lodging costs: I could fly cheaply within Europe or within North America, but pay a high cost each day, or I could drop more on a flight to India and make up the difference in my time there. With your suggested tax hike I’d just stop thinking about going to India or China or anywhere like that, but I’d still want to go on frequent trips over a shorter distance. Sadly, with my parents being across the Atlantic and my wife’s being in South America, I guess we’d just never see them any more. And I imagine that for those families in India or China who have relatives in Europe or North America, they’d just go back to the old model where they have to choose between permanent separation and eventual migration, right?

This is a link to Boeing’s 787 site . It claims 20% percent improvement in fuel burn over the current generation of similar-sized aircraft ( that’s 767, introduced in mid-80s and A330 from early 90s). I would say this is pretty much a high limit to the real improvement, since it is generated by Boeing’s marketing department. And as I mentioned before, airliners are jumping to the chance to get these improvements.

Another interesting link. This is a small NLR (Dutch Aerospace Laboratory) report about trends in fuel burn. Their conclusions are that the IPCC is overestimating the efficiency increase in the past, and that efficiency growth is slowing. They estimate a 55% percent decrease in fuel burn from the 707, the first successful jet from around 1960, to present jets, but the slowdown of efficiency growth makes a similar improvement in the next 40 to 50 years very unlikely.

Don’t get me wrong, I mostly agree with your thesis that we can reduce CO2 emissions without severely damaging life as we know and value it. But I think that here you are putting too much hope on technology improvements to do the heavy lifting. Especially in aircraft, where fuel burn has already been the driver behind technology for many decades, and the simple improvements are already made.

I have seen some reports that did try to estimate what should be done to reduce CO2 emissions by 50% , and they seem to conclude that it will require every not entirely unrealistic technology people have dreamed up, plus a shift to flying slower and lower ( lower actually hurts fuel burn, but apparently CO2 does less damage at lower altitudes).

Here is a Boeing research project incorporating just a few of those ideas. Even if you can’t understand of all the details, just look at the pictures to see the enormous difference from present aircraft. And then realize that developing a normal new aircraft costs already between 10 and 20 billion dollars.

BTW, I edited your comment to remove repetition and accidentally cut the para about Lufthansa. Sorry about that.

“Airliners will use part of that effiency to fly longer routes non-stop, and this increases fuel burn per mile again, ”

Can you explain this? It seems obvious to me that the opposite should be true – flying non-stop from NY to LA must use less fuel than landing in, and taking off from, Atlanta en route.

You happen to be right about LA- NY. But for really long-distance flight, you have to bring the fuel for the last part with you on the first part. For transpacific flight, over 40% of take-off weight is fuel ( meaning almost as much the entire aircraft would weigh empty), and this damages fuel economy on the first part. The result is a sort of ‘Laffer curve’ ;) , where for short distances fuel economy improves with distance because take-off is a smaller part of the total consumption, but beyond a certain distance fuel economy deteriorates as the fuel-carry penalty becomes big.

If you look at curves, fuel use per kilometer is best around 4000-5000 kilometer,close to LA-NY and close to the design range of the 767. The 787 is designed more for 9000 kilometer trips, and it will probably get permission to fly longer over oceans.

But rereading my post, I think I stressed this point too much. I used it more as an example how increased efficiency can eat its own gains, but that would be more a topic for your elasticity post.

Since 1991, for instance, we have increasingly succeeded in decoupling our transportation services from effects on the environment. Over this period our transport volume has more than doubled, yet our kerosene consumption has risen by only around 50 per cent. We intend to continue this trend. On average, aircraft ordered in 2006 will run on about 33 per cent less fuel than previous models

For domestic US travel, it seems pretty clear that B787/A350 planes are likely to dominate most routes, so it would be silly to assume 800 passengers per plane. But this post was about long-haul tourist travel, not about domestic US travel.

Can you explain this? It seems obvious to me that the opposite should be true – flying non-stop from NY to LA must use less fuel than landing in, and taking off from, Atlanta en route.

Obviously, there’s a load factor problem which is why airlines go for hub-and-spoke, but I assume that’s not your point. Since load factors are highly responsive to price incentives, my argument assumes that they will be pretty close to 100 per cent, at least for the kinds of journeys typically taken by tourists.

What about this issue of fuel-consumption improvements in new models, per-passenger versus the raw figures? Are the raw figures corporate secrets? If they were available might using them be semi-fatal to the overall argument here?

Well, detailed performance figures of yet-unbuild aircrfat, mainly its weight and air resistance, are not only secret, they are not even known for sure until the aircraft is ready and flying. But Boeing has to sell its 787 anyway, so they promise numbers to the airliners. If Boeing doesn’t make those numbers, it will pay a fine, if they improve on it they get a bonus, but they would have made more if they had promised the better numbers in the first place. So Boeing has a good incentive to show realistic figures to airliners. Those numbers are still confidential, but the overall idea seems to be that it will burn up to 20% less fuel than its very similar predecessor 767. Airliners will use part of that effiency to fly longer routes non-stop, and this increases fuel burn per mile again, so we can expect roughly 15% decrease in actual fuel burn per paxkilometer, compared to an aircraft with a 1980’s structure and 1990’s engines. This improvement is considered so big by airliners that the 787 is sold-out for the next 7 years or so.

I think this is pretty fatal to the argument. Technology is still improving , and there are enough new ideas for it to keep improving for many years to come. But there is absolutely no reason to assume a 50% reduction in fuel burn per passenger kilometer within the the next few decades.

People have often used improvements since the early jet aircraft to show that technology improvements are rapidly improving efficiency. But this is more a measure of the enormous inefficiency of early jet aircraft. In fact, the next generation of jetliners will be the first to use less fuel per paxkilometer than a 1950s propellor-driven Lockheed constellation (although, of course, at much higher speed and a lot safer). There is no reason to assume similar improvements in the future unless people will accept lower speeds and more stops en route, and even then improvements may less than expected.

Can I have a pony, too?

No, ponies are high-protein. Have some lettuce.

I understand completely all of your points, in fact I’m sure that most managers the world over would echo them. Change is risky and usually results in costly mistakes in the near term. But we are talking here about change that may be imposed on businesses by external factors.

Ignoring the climatic issues, it seems likely that there will be economic and regulatory changes that will effect the competitive playing field. Businesses will adapt sooner or later, and those that adapt sooner will come out ahead.

Adapting sooner means exploring process changes and technologies now, on a small scale rather than trying to catch up with your competitors after your business has fallen behind.

Frankly, I think this is a good place for government to take a leading role. Government and business share many basic processes and much that could be learned from government efforts would be directly applicable to business.

“Barry – You try to explain to people on the other side of the planet how it’s more friendly for them if they head into the office at night (where the god comms equipment is), instead of you heading over there to see them.”

At this point, I’m going to stop being ‘politically correct’, and start being honest:

If you are trying to sell something to them, and they are in a position of power, then you are going to head into the office at night. If vice versa, then vice versa. Why don’t you realize this?

“Then try selling your management on the idea that they should come in at 9 PM, or midnight. Good luck with that :)”

‘Joe, you wanna keep the business, you come in for some midnight conference calls. Otherwise, you spend 12-24 hours travelling, and meet them face to face, at midnight your biological time. And then spend 12-24 hours travelling back. Oh, you don’t get any lighter workload because you’re on the road.’

Which do you think that Joe will prefer?