Qatar Airways again wins Skytrax's airline of the year: Travel Weekly

Skytrax, which published its annual airline rankings on Friday, said thatQatar Airways is once again the best airline.

All Nippon Airways and Qantas rounded out the top five airlines.

Delta was the top rated carrier in the U.S. Southwest was one of the best low-cost airlines in the country.

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One of the most credible awards in the airline industry is the Skytrax World Airlines Awards. The winners this year were determined by an online survey that was open for six months in six languages. Responses from people of more than 100 nationalities came from the survey results.

This is the seventh time that the airline has been named the best in the world. In the last six years, the airline has won.

"To be named as the world's best airline was always a goal, but to win it for the seventh time and pick up three additional awards is a testament to all the hard work of our incredible employees," Akbar Al Baker said in a statement.

It was the top airline in the Middle East for its lounge dining and business class.