American Airlines operates a fleet of 300 older MD-80s, a model that guzzles fuel and lacks the latest in passenger comforts. And American has only a handful of replacement planes coming in the next couple of years.

The fleet of big jets operated by nine major domestic airlines has aged steadily since 2002, according to Airline Monitor, an aviation research firm. The average age was 10.6 years at the end of 2002, and it has risen each year, hitting 12.2 years at the end of 2006. Domestic airlines largely stopped ordering new planes after Sept. 11, 2001, shrinking their fleets to adjust to a drop in demand. Travel has rebounded strongly, but airlines are, for the most part, years away from taking delivery on large numbers of new planes. A big reason is that Boeing and Airbus have committed most of their airliner production capacity in coming years to carriers outside the United States." (NY Times)