An IATA official has recently been quoted as saying that, 'A slot management system is indicative of a failure of governments or airports to invest in adequate infrastructure to keep pace with airline demand.'

Should governments and airports always invest to meet airline demand?

Consider the issue of de-peaking. Until recently, airlines worked on a hub-and-spoke basis, scheduling large numbers of flights in and out of hub airports in 3-4 waves each day - early morning, lunch time, late afternoon, and evening. They all connected with each other and then flew off again.

Surprise, surprise - this caused overloading of facilities at peak times and under-utilisation out of those peaks. What did airlines do? Why, they de-peaked at key airports.

Aircraft still came into hub airports in those waves, but their departure was sometimes re-scheduled so that the peak load on check-in and baggage staff was reduced.

So - by IATA's argument - airports should have invested in capacity for the peak caused by the historic hub-and-spoke operation when that became fashionable. They would, of course, then have been left high and dry by the subsequent de-peaking, having invested in long-life assets which the users no longer wanted!

Consider the fact that aircraft are mobile assets and airports are not. Some airlines will - rightly - try a route for a season or two to see if they can make money out of it. If they can't, they pull out. So what should the airport do? How much should they invest for an operation which might not last beyond tomorrow?

And consider the impact of frequent flights by small aircraft or less frequent ones by larger aircraft (an issue studied, incidentally, in ACRP Report 31, available on the TRB web-site).

If an airline schedules a 50-seat plane every half hour instead of a 100-seat plane every hour, it takes up twice as many slots for the same number of passengers. OK, on this one you could argue passenger convenience - all other things being equal, people prefer frequency. But is it really worth it - is it a good use of scarce runway and slot capacity?

Is it worth increasing capacity - as IATA suggests - for this kind of thing?

To me, the killer argument here is that of San Diego. This is the busiest single runway airport in the United States, handling 17 million passengers a year. It has spent much time, money and effort looking for ways to increase capacity because, it is said, it's full.

But look across the Atlantic, to Gatwick - the busiest single runway airport in the world, handling exactly twice as many passengers! The key difference is aircraft size.

The predict and provide policy - predicting demand then providing infrastructure to meet it - has been discarded in other areas. How much does IATA need to catch up with this? Because another leading IATA manager has been quoted as saying that airports should use their charging system to re-distribute traffic - a peak charge signals the cost of the additional infrastructure needed for the peak.

A colleague recently moved from the aviation industry to the rail industry. The key difference he noticed was that the former was always planning for growth, whereas the rail industry was planning for a steady state.

This led me to wonder what the aviation industry would look like if it wasn't always growing! I have as yet come to no conclusions, but there was an interesting presentation at the TRB Annual Meeting in January which showed that air passenger growth might be slowing significantly.

And, logically, it cannot continue. In my lifetime, fares have continued to drop in real terms, and this has led to the growth in air travel we have seen. Can this go on?

Your thoughts would be appreciated!

The rail connection to Bangkok's Suvarnabhumi Airport opened today - and it looks good, with a choice of an Airport Express or a commuter train as well as in-town check-in facilities at the Airport Express's downtown terminal.

I had a look at the airport's web-site to see how well the link was publicised - after all, it could bring both business and prestige to the airport.

I went to www.bangkokairportonline.com then clicked on Transportation then on Airport Express - and got details of the express bus service into the city!

You have to click on Rail Link to get any information about the railway - and that is badly out of date. Full service is expected in early 2010! There are no links to the airport railway (note to searchers - it's on www.bangkokairporttrain.com).

Sad - and a waste of a valuable resource for the airport.

There are debates about what an Airport Express really is - express laundry? express coffee?

In Bangkok, it's the four bus routes who got in first with the brand name. In Chicago, it's the minibus (or shared-ride van) service.

It's a pity - from the customer information point of view - that we can't standardise on this!

Probably the best name is the one in (Wien) Vienna. The stunning airport express there is called the City Airport Train - what could be clearer than that?

A colleague has made the interesting suggestion that it may be time to rethink how classes of service on trains are described or branded. He comments that the standard of accommodation on many first class train services is similar to premium economy on an aircraft.

He also speculated that occupancy might rise if the service was branded Premium or Business Class, since most companies have a travel policy which is aimed at finding the best business class service.

In addition, he raises the question of airlines which offer a rail service as a complimentary feeder service between airport and specific domestic destinations for certain fare types. Should this be a premium rail service for a premium air traveler? This is likely to depend on the traveler profile and the policy of the individual carrier.

Fascinating stuff!

As an economist, I approve of the concept of providing a number of classes and therefore a number of prices. It helps to maximise revenue, and it improves customer choice.

However, one needs to be culturally aware - in particular, of what to call the two classes.

In Japanese trains, there is Ordinary Class and Green Class. On some, you pay less if you have to stand: you can also have a compartment in Green Class which costs more than the ordinary Green Class, effectively making 4 classes.

On the Dubai Metro there is Gold and Silver Class.

I'm glad the UK rail network changed form Second Class to Standard Class: the argument was that you shouldn't be calling 80% of your passengers "second class"!

Heathrow Express had a big debate about what to call its classes: they decided on First and Express (and the term 'Express' was my idea!). First and Business was decided against, on the grounds that lots of people weren't travelling first class and were not travelling on business!

Amtrak provides coach and business class on the Acela Regional trains, and business and first on the Acela Express.

I was fascinated to learn recently about the Club Car on New Jersey Transit. A group of people pay to have a dedicated car attached to one peak train each way: the car has more comfortable seating and more leg-room than the average commuter car. Passengers pay their fare to NJT and a supplement for travel in the Club Car. You can pay by the day or for a month.

Moving on to the second point, I'm pretty sure that those airlines which offer complimentary rail travel in conjunction with a flight only offer first class. I also understand that the take-up of rail is good - at one stage, people like Virgin Atlantic and Emirates were offering their preferred passengers a choice of a limo or Gatwick Express to London, and most chose the train because of its reliability.

On both the Stuttgart and Cologne to Frankfurt and the Brussels Midi - Paris CDG air-rail code shares, all rail travel is in first class.

One reason for the unpopularity of the short-lived code-share between SN-Brussels and Thalys on the Paris Gare du Nord - Brussels Airport sector was that rail travel was in Confort-2 class and not Confort-1.

I'm not sure what happens on other rail-air code-shares.

It was also interesting to see that American Airlines now offer what they call Express Seats! Customers can buy seats in the first few rows of Coach, including bulkhead seats. In addition to sitting in the front of the main cabin, the Express Seats option also includes being in Group 1 of General Boarding, providing the benefit of being among the first Coach customers to board the plane. Express Seats can only be purchased at airport Self-Service Check-In machines between 24 hours and 50 minutes before flight departure, on flights within the United States, Puerto Rico and the U.S. Virgin Islands.

This has been done by Ryanair for a while - passengers can pay a priority boarding fee to be among the first to board - and therefore to have the best choice of seat. I do not know whether there is any limit on the number sold - could everyone buy priority boarding?

So what do you think? Should first class rail be re-branded? To what?

As the new class 377 trains have been introduced onto the Thameslink route (connecting Luton and Gatwick Airports to London) I've been hearing but not really noticing the announcements on platforms as they approach.

One thing I did notice last night - and started to think about - is an element of laziness.

The 4-car units have a first class section at each end.

But regardless of whether the train has one or two 4 car units, the announcement is always to the effect that 'First class accommodation is at the front and rear of the train'.

So it is, of course, but if it's an 8-car train it's also in the middle! And there are plenty of stations where you might wish to alight and you might wish to be in the middle of the train rather than at the front or rear for speed of egress. Especially with ticket barriers making it more of a scrum to leave the station!

Is this someone taking the easy way out and ignoring the passengers? Especially the premium passengers?

The current management seem to have cracked this counting business: if a 4-car train is announced, it's likely to have four coaches. With the previous guys, you knew that there were two kinds of 4-car train - those which actually had four coaches and those which had 8. There were also two kinds of 8-car train, which was sometimes distressing because it necessitated a sprint!

Now that counting has been cracked - or so it seems - it ought to be possible to have separate announcements for 4 and 8 car trains. The next Great Leap Forward!

I have blogged before about the new trains being introduced to First Capital Connect's Thameslink route connecting Gatwick and Luton Airports to London.

They look nice, and they are air conditioned.

A downside I have noted before is the lack of seats - they have about 50 fewer in a 4-car unit than the class 319s they replace (although at some time in the future they will run as 12-car formations, when all the platforms on the route have been lengthened).

Another is that they ride very firmly - downright roughly in places, almost to the point of being alarming. I've only sampled them north of the Thames - I wonder what they are like to the south, where the railway is even more heavily used?