Best Airlines: Airline Quality Rating Ranks American Carriers (PHOTOS)

The topic of which airline is the best is a much-debated one -- every traveler has an opinion as to which carrier is tops. To quantify all of those opinions, the folks at Wichita State University and Purdue University have once again released their Airline Quality Rating.

According to the survey, the performance of leading U.S. carriers has improved for the fourth consecutive year, earning the highest marks of the project's 22-year history.

The Airline Quality Rating ranks carriers by four criteria: On-time performance, baggage handling, involuntary denied boardings and customer complaints. Both the 2011 and 2012 surveys resulted in the same top-three airlines. See the full rankings below. For the full results of the survey, including how each airline performed in each category, visit the Airline Quality Rating's website.

Also, check out America's best and worst airports for flight delays, and the best airline food around the world.

Do you agree with the rankings? Leave it in comments.