If your air cargo shipments through major East Coast air cargo hubs, particularly New York and Miami, are taking longer to reach their final destination, you're not alone.

"They're all really maxing out," says one aviation research consultant, referring to the big hubs. "Not just their runway capacity, but in their ability to build new facilities."

The crunch has prompted cargo operators to look at airports in other parts of the U.S. as viable alternatives for moving international air cargo into the Eastern part of the United States.

Where are some of the alternatives? Along the East Coast, Boston, Washington Dulles, and Philadelphia have all gained flights from some of the biggest carriers, including Lufthansa, British Airways, Virgin Atlantic, KLM Royal Dutch Airlines, Air France, Austrian and SWISS. Other airports picking up cargo business are Buffalo and Atlanta.

Although New York remains the number one international air cargo gateway in the U.S., the Big Apple's 'big worm' is chronic roadway congestion, which hampers the quick delivery of goods, say transportation executives.