This rise in fuel prices is going to affect some of the more financially troubled airlines, like United, US Airways, and Delta, who have not been able to hedge as much of their fuel (or none at all) costs as airlines in less financial troubles. When you've got vendors wanting cash upfront for their services that they used to bill you for, that's when you know you're in financial troubles. Some airlines are not able to hedge fuel because the suppliers fear that those airlines won't be able to pay for the fuel when the bill comes.
The rise in fuel prices over the last nearly four years also came at a time when the industry began the downward trend in its' cycle. The rise in fuel costs was one of the reasons why National (N7) filed for CH
. 11, and affected the bottomline at a number of carriers. Some of the smaller carriers that folded in the aftermath of 9/11 were already hurting at the time of the attacks because of the rise in fuel prices and the downturn in traffic even before 9/11. A few of these carriers were already in their death spirals, and 9/11 put the final nail in their coffin. Some of the larger airlines were still flush with cash from the heady days of the late 1990s, when the loads were high as were the profits, so they were able to hedge a good bit of their fuel costs. It was the smaller airlines that were having trouble with hedging fuel costs. Airlines like AirTran and Frontier were only able to hedge a small percentage of their fuel costs, and with the introduction of newer a/c, those fuel costs savings helped in the long run. Imagine what kind of financial straits airlines like AirTran and Frontier would be without those newer, more fuel efficient a/c.
Look to see older a/c types like the 737-200 and 767-200 to slowly be pulled out of some airlines' fleets due to the higher fuel costs. I would even venture to say that some older MD
-80s could find their way out as well. And I doubt Northwest will pull too many DC-9s out of service, as they've seemed to found a balance between the fuel costs and the costs of replacing those a/c.