There is some troubling news Friday for Long Islanders using the biggest airline at MacArthur Airport.Southwest Airlines has been fined more than $10 million for not properly inspecting its older planes. Federal officials say instead of grounding the planes, the airline continued to fly them. According to officials, some of the planes were starting to crack.The airline insists it has complied with all government regulations and plans to fight the fine. A Southwest spokeswoman says the airline found "very small" cracks on six planes.Travelers that spoke to News 12 Long Island said the report was troubling and made them a little more nervous about their flights.