This weekend is one of the greatest annual events in racing: the 24 Hours of Le Mans. Here's our guide to the ultimate endurance event.
The Circuit de la Sarthe is 8.5 miles (13.6 kilometers) and 38 corners of tarmac in north-western France. It's a mixture of purpose-built racetrack and public roads. Most of the year you can drive down the Mulsanne straight!
Nowadays the Mulsanne features a couple of chicanes to slow cars down along its 3.7 mile length. World motorsport governing body the FIA refuse to sanction any race at a circuit with an uninterrupted straight longer than 1.2 miles, for safety reasons.
The speed record on the new layout is still 226.9 mph (366 km/h). This came about when the wastegate on Mark Blundell's Nissan engine turbochargers stuck closed, massively increasing the boost pressure and giving the team pole position in an unusual manner.
The race lap record is 3:17.297 by Toyota's Mike Conway in 2019. This year's hypercars are a little slower than the 2019 LMP1 cars.
The 24 Hours of Le Mans is a timed race. The chequered flag is waved when the leader crosses the line after the time has elapsed. Cars have teams of three drivers who take it in turns to race the car and swap over every few pit stops. There are rules on the minimum and maximum drive time for each driver.
Parts of the circuit are unlit and so drivers will rely on their headlights through the night. This makes multi-class racing especially challenging weaving through traffic in the darkness.
There are plenty of familiar names lining up at Le Mans this year. F1 fans will recognise Kamui Kobayashi, Sebastian Buemi, and Brendon Hartley in the hypercar class.
LMP2 drivers include Juan Pablo Montoya, Paul Di Resta, and new Formula E world champion Nyck De Vries.
Other drivers you may recognise include Tatiana Calderon, Alex Lynn, Stoffel Vandoorne, Tom Blomqvist, Giedo Van Der Garde, Antonio Felix Da Costa, and Kevin Magnussen.
The Le Mans 24 is a round of the FIA World Endurance Championship but also has entrants from other series by invitation. These cars have to survive a full day of racing! There are now five categories:
Hypercars and Prototypes
New Hypercar regulations have replaced the old LMP1 category. Hypercars are specialised prototypes or cars based around road-going vehicles. The FIA and ACO hoped to attract race versions of the McLaren Senna and the Aston Martin Valkyrie but so far only have entries from Toyota, Alpine, and Glickenhaus.
LMP2 is the second category. An LMP2 is a price-capped, homologated, purpose-built racing car with a closed cockpit. There are no manufacturers in this category: teams have to be independent. Most teams this year are using the Oreca chassis and all are using the Gibson engine.
GT and the Innovative Car
There are two categories for GT cars: LMGTE Pro and LMGTE Am. The FIA describe LMGTE cars as "racing cars derived from street models for everyday road use from some of the most prestigious luxury car manufacturers." The only difference between the two classes is the experience of the drivers. Am teams must include at least 1 bronze-rated driver and another bronze or silver-rated driver in the crew of drivers.
GTE cars have the option of traction control. They are also performance balanced, meaning that the organisers can add weight or reduce the power of a car to make the field more competitive.
There's also a fifth class: the "innovative car" which is open to cars that don't fit the rules of other categories, by invitation. We'll be watching the Association SRT41 car, driven by three racing drivers with amputations or paralysis.
Watching the 24 Hours of Le Mans
The UK broadcast is on Eurosport 1 and Quest. Coverage starts at 1.45pm Saturday on Eurosport and at 2.15pm on Quest.
In the US and Canada, the broadcast starts at 10am EST on Saturday on MotorTrend TV and Velocity respectively. In either country, you can also watch via the MotorTrend app.
The race starts at 3pm BST on Saturday, that's 10am EST.
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