Old, fuel-guzzling jets tax Northwest

Complicating matters for Northwest Airlines as it struggles through its mechanics’ strike: The USA’s No. 4 carrier flies very old planes.

Northwest’s planes average 18.2 years, by far the oldest fleet of any major U.S. airline, according to industry tracker Back Aviation Solutions. Its oldest planes are nearly 40 years old.
The older planes, designed and built in an era of cheap fuel, are deepening the carrier’s financial troubles as oil prices soar toward $70 a barrel. And the older planes