American Airlines debt load is raising eyebrows on Wall Street, with analysts worrying about its ability to pay its bills if the economy slows down. The carrier had US$22.3b in long-term debt and capital leases, net current maturities, at the end of September, a quarterly financial filing shows. That was up 1.8% in Q3, and up less than 1% year-over-year. The amount is nearly $10b higher than United Airlines, and nearly $15b higher than Delta Air Lines. "American will be left with a material non-operating expense disadvantage if the economic cycle deteriorates significantly," write JP Morgan analysts in a report Tuesday, echoing concerns raised by other analysts during American's Q3 earnings call earlier in October. <br/>