As airline service worsens, the big five airlines are again raising their domestic fares, this time by $10 per round trip.

The increases were announced on Thursday by United, Delta, Continental, Northwest, and America West. Discount carriers, Southwest and JetBlue did not match the hikes.

For the second year in a row, low-fare airline JetBlue Airways earned the number one ranking in the annual (AOR) Airline Quality Ratings study.