I wonder if the problems DL, NW etc face are more subtle. They are hub carriers with hugely complex networks. Fact is that I don't think they have a clue how much money (if any) they make from any part of their operation. So how can they run it ?
Yield management is a very complicated subject. What is a passenger worth on a sector when they are holding a multiple segment ticket ? How do you allocate costs vs revenue ? Probably on a set of very dodgy assumptions.
So I would submit these carriers problems are fundamental. They don't have a clue about their business on a per sector basis (other than costs) so how can they run them.. Revenue/Yield management experts please chip in and explain.....
Also aren't the real winners in the airline game people like GE Capital Finance (see radarvector's link to
http://www.startribune.com/stories/535/5619768.html ) and companies like American Express, as long as they keep airlines afloat, they make money....