Travel Globe

Patrick Farrell/Miami Herald via AP, file

The Royal Caribbean cruise ship Allure of the Seas is seen in a file photo as it pulls into Port Everglades in Ft. Lauderdale, Fla., in 2010.

A woman who is believed to have fallen overboard from a cruise ship off Florida Sunday night is still missing, and U.S. Coast Guard crews are combing the Atlantic for her, officials told NBC News Tuesday.

The 21-year-old woman, who is from Bartlett, Tenn., was on a Royal Caribbean Allure of the Seas ship 47 miles east of Fort Lauderdale when she reportedly fell into the ocean.

Crew members searched the cruise ship Sunday night for the woman; when they couldn't find her, the captain alerted search-and-rescue officials at the Coast Guard in Miami.

Florida's Sun Sentinel reported a fellow Allure of the Seas passenger saw the woman go overboard around 9:25 p.m. Sunday; the ship's camera footage later confirmed she had gone into the water, Royal Caribbean told the paper. 

A call from NBC News to Royal Caribbean was not immediately returned. 

As of Monday, the Coast Guard's search area spanned approximately 320 square miles. In addition to searching by boat, the Coast Guard used four aircraft, but the woman -- whose identity was not made public -- was not found.

A Coast Guard spokesman provided no additional details, including any information on the cause of the woman's fall.

Allure of the Seas has been in service since December of 2010 and has a capacity for 5400 guests, according to Royal Caribbean's website.

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The number of long delays in July involving planes stuck on airport tarmacs was more than the previous eight months combined, the government said Monday. 

Twenty eight planes were stuck on the ground at U.S. airports for more than three hours that month, the height of the summer travel season. Eighteen of those planes were operated by U.S. carriers.

Sixteen of the U.S. flights were going in or out of Chicago O'Hare on July 13, a day of severe thunderstorms. All of the longest delays were on regional carriers that operate smaller jets for larger airlines.

There was only one international flight that sat on the ground for more than four hours, and it's susceptible to a big fine. Caribbean Airlines flight 526 from Georgetown, Guyana, to New York's JFK Airport sat on the ground for four hours and three minutes. U.S. and international airlines can be fined up to $27,500 per passenger if a flight is stuck for more than three hours.

The last time there were more three-hour delays in a single month was October 2011. There was just one long delay last July.

Overall, flights were less on-time in July than they were in both June 2012 and July 2011. United Airlines, which has a base in Chicago, had the worst on-time rate. US Airways had the best on-time rate for a network carrier, but Hawaiian Airlines and Alaska Airlines topped the overall list.

As more flights were stuck and passengers grew frustrated, they complained much more. The Department of Transportation received just under 2,500 complaints in July, almost double a year earlier and up 50 percent from June.

They also had more reason to complain about lost or damaged bags. The mishandled baggage rate fell from a year earlier but was up from June. 

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