Northwest and Delta airlines filed for bankruptcy Wednesday, citing heavy debt, expensive pensions and rising fuel costs. Analysts say Iowa fliers shouldn’t see much impact as both airlines will continue to operate. Northwest C-E-O Doug Steenland says the biggest battle the carrier is facing is with fuel.Steenland says “I think there have been something like 40 fare increases over the last several months, many of which we led to try to pass our fuel costs on. So fuel has gone up 50-percent and airlines as a whole have been able to raise their unit revenues in the three to five percent range.” Northwest is based in the Minneapolis area and flies to Sioux City, Fort Dodge, Mason City, Waterloo, Cedar Rapids, Des Moines, the Quad Cities and Omaha/Council Bluffs. Steenland says consolidation in the airline industry is likely. Steenland says “I think everybody recognizes that at present there is too much capacity, too many seats chasing customers out there and that excess capacity is one of the primary reasons airline have a very difficult time passing through cost increases, like the huge increase in the cost of fuel.” Delta is the nation’s third-largest U.S. Airline and Northwest is the fourth-largest. They’re the third and fourth major U.S. airlines to file bankruptcy since the 9-11 attacks, following United and U.S. Airways.