INDIANAPOLIS - ATA Airlines, the nation's 10th-largest carrier, filed for bankruptcy protection Tuesday and sold off airport slots and other assets to AirTran Airways Inc. for $87.6 million, to become the latest U.S. airline tripped up by rising fuel costs and fare wars. Orlando, Fla.-based AirTran Holdings Inc. will assume ATA's flight operations, gate leases and routes at Chicago Midway Airport and arrival and departure slots at New York's LaGuardia Airport and Ronald Reagan (news - web sites) Washington National Airport. The deal is subject to approvals by the bankruptcy court and other entities and is expected to take effect...