American, United Raising Fares: The nation's two largest airlines plan to raise fares between $10 and $30 next week on routes left unchanged in last month's round of increases. The fare hikes will affect about a tenth of United Airlines' markets, including several transcontinental routes, said airline spokesman Joe Hopkins. American Airlines spokesman Tim Smith said the nation's largest carrier would match the fares. The increases, due to take affect Friday, will typically raise fares between $10 and $30. But some routes would go up more. For instance, Los Angeles-New York fares will go up $50 to $470.