United Airlines hikes fares by $10

/ Source: The Associated Press

United Airlines, the second-largest U.S. carrier, raised its fares by $10 round-trip on most domestic flights to help offset the high price of fuel, a spokeswoman said Friday.

The increase is the fourth attempted by the airline industry so far this year, according to a tally by FareCompare.com, which tracks changes in airline ticket prices. Two of those have been largely successful, FareCompare.com said.

Fuel is one of the airline industry's biggest costs, and the surge in oil prices is threatening to erase the profit margins airlines have managed to achieve in recent years. Crude prices climbed back above $100 a barrel earlier this week. On Friday, light, sweet crude for April delivery rose 58 cents to settle at $98.81 a barrel.