Chicane
Encyclopedia
A chicane is an artificial feature creating extra turns in a road, used in motor racing and on city streets to slow cars
Traffic calming
Traffic calming is intended to slow or reduce motor-vehicle traffic in order to improve the living conditions for residents as well as to improve safety for pedestrians and cyclists. Urban planners and traffic engineers have many strategies for traffic calming...

 to lower speeds.

Motor Racing

On modern racing circuits, chicanes are usually located after long straights, making them a prime location for overtaking. They can be placed tactically by circuit designers to prevent vehicles from reaching speeds deemed to be unsafe. A prime example of this is the Tamburello chicane at Autodromo Enzo e Dino Ferrari
Autodromo Enzo e Dino Ferrari
The Autodromo Internazionale Enzo e Dino Ferrari is an auto racing circuit near the Italian town of Imola, east of Bologna and east of the Ferrari factory in Maranello....

, which was placed after Ayrton Senna's death
Death of Ayrton Senna
The death of three-time Formula One World Champion Ayrton Senna on May 1, 1994, occurred as a result of his car crashing into a concrete barrier while he was leading the 1994 San Marino Grand Prix at the Autodromo Enzo e Dino Ferrari in Italy. The previous day, Roland Ratzenberger had been killed...

 at the original corner. At Circuit de la Sarthe
Circuit de la Sarthe
The Circuit des 24 Heures, also known as Circuit de la Sarthe, located near Le Mans, France, is a semi-permanent race course most famous as the venue for the 24 Hours of Le Mans auto race. The track uses local roads that remain open to the public most of the year...

, chicanes were placed alongside the 6-km Mulsanne straight in order to slow down Le Mans Prototypes
Le Mans Prototype
A Le Mans Prototype is a type of sports prototype race car most notably used in the 24 Hours of Le Mans, American Le Mans Series and Le Mans Series...

, which with Group C Prototypes went to speeds as high as 400 km/h.

Some tracks, such as the Yas Marina Circuit, feature optional chicanes. Faster cars will take the chicane, but slower cars (such as amateur club racers) may avoid the chicane because they are not capable of reaching equally high speeds on the straights. Such chicanes are used at Watkins Glen International
Watkins Glen International
Watkins Glen International is an auto race track located near Watkins Glen, New York, at the southern tip of Seneca Lake. The facility is owned by International Speedway Corporation...

 and Daytona International Speedway
Daytona International Speedway
Daytona International Speedway is a race track in Daytona Beach, Florida, United States. Since opening in 1959, it has been the home of the Daytona 500, one of the most prestigious races in NASCAR. In addition to NASCAR, the track also hosts races of ARCA, AMA Superbike, Grand-Am and Motocross...

, where there are separate chicanes for cars and motorcycles.

Another example of this is the Tsukuba Circuit
Tsukuba Circuit
The Tsukuba Circuit is a motorsport race track located in Shimotsuma, a neighboring city of Tsukuba, Ibaraki Prefecture, Japan. It is long, has 32 pits and the longest straight is long. There is a small chicane corner that is used for motorcycle racing only and increases the total length to...

 in Japan. A chicane was added after Turn 5, creating a right turn, followed immediately by a left. This chicane is used only for motorcycles. It was implemented to divert motorcycles from taking Turn 6, which is a high speed long sweeping left corner. Turn 6 was deemed to be unsafe for motorcycles, as immediately following this is a slow right hairpin corner. This means riders may still have been leaning to the left when being expected to begin braking for Turn 7.

The term is used in other types of racing, including bobsleigh
Bobsleigh
Bobsleigh or bobsled is a winter sport in which teams of two or four make timed runs down narrow, twisting, banked, iced tracks in a gravity-powered sled that are combined to calculate the final score....

 and dogleg
Dogleg
Dogleg or dog-leg may refer to:Motor vehicles*Dog leg, an unusual manual transmission layout*Dog-leg, an offset 'zig-zag' plane of operation for a floor-mounted automatic transmission shift lever* The area behind the rear door on a four door car...

, to indicate a similar shift in the course or track.

"Mobile chicane" and "moving chicane" are terms often used to describe slower drivers and vehicles who hold other competitors up. In some cases they may not move out of the way quickly enough to allow competitors in higher positions (having completed more laps) past, despite repeated showings of blue flags. This can cost competitors valuable time and championship points. This same term, applied to traffic calming, can refer to the usage of portable devices to create a chicane configuration.

Chicanes such as those at the Yas Marina Circuit in Abu Dhabi have become a subject of debate. For example, some of Formula One's top drivers feel that the chicane after the back straight disrupts the flow of races and impedes overtaking maneuvers.

McLaren Team Principal Martin Whitmarsh feels that placing high speed corners after straights is a better option than using chicanes.

Traffic Calming

Chicanes are a type of "horizontal deflection" used in traffic calming schemes to reduce the speed of traffic. Drivers are expected to reduce speed to negotiate the lateral displacement in the vehicle path.

There are many variations of traffic calming chicanes, but they generally fall into one of two broad categories:
  • single-lane working chicanes, which consist of staggered buildouts, narrowing the road so that traffic in one direction has to give way to opposing traffic
  • two-way working chicanes, which use buildouts to provide deflection, but with lanes separated by road markings or a central island.


Limited accident data for chicane schemes indicate a reduction in injury accidents (54%) and accident severity.. However, traffic calming chicanes also occasionally lead to the deaths of vulnerable road users.
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