Southwest Airlines is known for its blue, red and yellow planes flying across the country, but some aircraft sport paint jobs that are unique.

A dozen Southwest Airlines Co. (NYSE: LUV) aircraft feature state flag designs that wrap the entire aircraft. States such as Colorado, Texas, Florida and California each have their own design.

There is no exact science to determine which states get their own paint job, but they usually are unveiled around significant service anniversaries. For example, Southwest unveiled Louisiana One last year after serving the Bayou State for nearly 40 years.

PHOTOS | Special Southwest Airlines paint jobs

Once a state flag livery is completed, it becomes a permanent fixture of the Southwest fleet. It takes several days to repaint planes as some state flags are more intricate than others.

In some cases, the airline has repainted old state flag liveries that started on Boeing 737-300 aircraft onto new 737-700 planes, said Brandy King, Southwest director of External Communications.

Read more at the Denver Business Journal |

PHOTOS | Special Southwest Airlines paint jobs

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