Gull-wing door

A gull-wing door, also known as a falcon-wing door or anhedral door, is a car door hinged at the roof rather than the side, as pioneered by Mercedes-Benz 300 SL, first as a race car in 1952 (W194) and then as a production sports car in 1954.

Opening upwards, the doors evoke the image of a seagull's wings. In French, they are called portes papillon ("butterfly doors"), although the term butterfly doors usually refers to a different design. The papillon door was designed by Jean Bugatti for the 1939 Type 64, 14 years before Mercedes-Benz produced its similar, famous 300 SL gullwing door. The papillon door is a precursor to the gullwing door, and is slightly different in its architecture, but is often overlooked when discussing gull-wing design. Conventional car doors are typically hinged at the front-facing edge of the door, with the door swinging outward horizontally.

Apart from the Mercedes-Benz 300 SL of the mid-1950s and the Mercedes-Benz SLS AMG, the best-known examples of road-cars with gull-wing doors are the DMC DeLorean from the 1980s and the Tesla Model X of the 2010s. Gull-wing doors have also been used in aircraft designs, such as the four-seat single-engine Socata TB series built in France.

While a gull-wing design is typically used for doors into the passenger compartment, some cars have used a similar design on the engine compartment doors, such as the De Tomaso Mangusta, as well as for the door windows only, such as the BMW Nazca C2 and Chevrolet Corvette Moray concept cars.