Theme: Illinois's bald eagle
When the US carrier Southwest Airlines decided to honour the state of Illinois with a specially designed aeroplane livery, some argued that a picture of Abraham Lincoln (the former president, who grew up in the state) might have been most appropriate. The airline, however, eventually opted for the more streamlined, so to speak, theme of a bald eagle to represent the so-called Prairie State. The design required some 400 litres of paint, and took 26 people six days to paint.
Southwest's Florida One aeroplane (the lower of the images above), stands out for its cheery use of colour. The design, the airline's seventh tied to a US state and based on Florida's state seal, took 32 people eight days to paint, using 16 different colours. Other Southwest aeroplane liveries have included Slam Dunk 1, a tribute to the airline's NBA partnership, and Triple Crown One, dedicated to the airline's baggage handlers. (They would probably have preferred a bonus, but there you go.)