Audi race engineer Leena Gade has won the Le Mans 24 Hours three times with her driver team of Marcel Fässler, André Lotterer and Benoît Tréluyer and before they make their bid for a fourth title this year, she explains just why the classic race, which starts at 2pm on Saturday, is like nothing else in motor sport

The Le Mans 24 Hours is the greatest sports car race in the world and these days the highlight of the FIA World Endurance Championship as well. It remains one of the hardest tests for teams and drivers in motor racing and is one of the most satisfying to win, certainly it has provided some of the very highest points in my career.

Within the 24 hours we pack the equivalent of a whole Formula One season into one weekend. The cars are designed freely within the regulations using very different concepts and feature some of the most talented and experienced drivers in the world competing head to head. Manufacturer teams rub shoulders with privateers across four different classes where there is always a chance a team can have their day, as over 250,000 fans throng the track over the weekend.

After the race, the car looks like it’s been through a real battle but even so on the surface you can’t often see how close to the limit we run. It’s only after the detailed analysis of every part that it becomes clear just what a feat of engineering it is to make cars that are bulletproof for what is now basically a sprint race over 24 hours. It is such a great race, such a spectacle and this year has the potential to be a real thriller, here’s some of the key details to help you enjoy the contest.

THE UNIQUE CHALLENGES OF LE MANS

This is a race like no other. First up is the weather, it can be chucking it down on the Mulsanne straight and bone dry in the pit lane, so reading the information and making the right tyre choice or strategy call is absolutely key. Equally, running for 24 hours means you encounter every scenario a normal day holds – it can be sticky and hot during the afternoon and almost down to single-figure temperatures during the night. The car reacts to that in terms of engine performance and tyre behaviour and then there is driver fatigue to take into account. All those scenarios need to be managed while staying awake for 24 hours, we don’t take breaks and see the job through from start to finish, so beating the tiredness is another challenge, which doesn’t actually get any easier with experience.

Finally, although it is a long race, you have to learn not to panic, it’s easy to do and make the wrong call. Howden Haynes, a former colleague, taught me that before you answer on the team radio, take a deep breath then speak. Which makes a huge difference because you automatically calm down and can give reasoned responses and questions to the driver or team.

THE TRACK

The Circuit de la Sarthe is 8.47 miles long. It couldn’t be further away from traditional F1 circuits, while a lap takes just under three and a half minutes. Mostly made up of public roads there are 38 corners but it remains very quick, with over 80% of the race spent at full throttle.

Audi race engineer Leena Gade has won the 24 Hours of Le Mans, racing’s toughest test of team, car and drivers, three times. Photograph: Richard White

Unsurprisingly then, it’s a low downforce track and with such long straights aero packages are uniquely designed to exploit drag characteristics. However while that works on the Mulsanne straight or on the long run to the Indianapolis, you still need downforce in the corners, especially the Porsche Curves. So a good balance between the two is what we aim for but without losing focus on the mechanical grip. That is important in the lower speed corners where the tyre grip can’t be hidden under the aero performance.

Because of the length of the race, this grip really builds up as more rubber goes down until sunrise on Sunday – what we call “happy hour” – which is probably my favourite time. This is when you truly see the potential of the cars. Tactically, it also sets up the scene for the remaining seven to nine hours. At La Sarthe this is when you can win it or bin it.

THE CARS

There are four categories of cars at Le Mans and at Audi we run in the top Le Mans Prototype 1 (LMP1) class, against factory teams from Porsche, Toyota and Nissan. The regulations governing the racing are not nearly as confined as in Formula One, so the teams are free to come up with different ways of designing and building their cars.

Our R18 e-tron quattro has a top speed of around 200mph, running on a V6 diesel engine and a flywheel-based hybrid energy recovery system (ERS). Manufacturers are allowed to harvest differing amounts of energy and the R18 has a 4 mega joule capacity. Porsche run a V4 petrol turbo engine, with a battery-based ERS, harvesting energy from the the front axle and the turbo. They have stepped up to the maximum 8MJ capacity and the car has huge straight-line speed, bringing a real challenge for us to try and overcome. Toyota are the reigning World Endurance Championship title holders and are not at Le Mans to come second. Their car is powered by a V8 petrol engine, with a super-capacitor-based 6MJ ERS that delivers power to both the front and rear axles. Nissan are the new boys this year and have brought an alternative concept. Their V6 petrol engine is front-mounted and the car is front-wheel drive and has flywheel-based ERS delivering 2MJ of energy.

It’s really exciting to have so many differing answers to the questions that Le Mans poses and that’s just in the top category. There will be 56 cars on the grid on Saturday across four classes: LMP1, LMP2, GTE Pro and GTE Am, including entries from Ferrari, Aston Martin and Chevrolet.

RACE STRATEGY

The main focus on strategy at Le Mans revolves around tyres, because a pitstop is effectively a time penalty during the race. So everything revolves around getting the best lap times and performance from a set of tyres for as long as possible. But fuel usage is also important, if you can tick over to another lap in a stint, it ultimately reduces the number of laps you fuel for at the end of the race.

In terms of drivers the order in which they get in the car is pre-planned and remains the same unless there is an illness to be taken care of or if a driver isn’t feeling comfortable. However, we’ve played around with our driver order already this year so that we had the fastest driver in the car for the bulk of the first round of the World Endurance Championship at Silverstone. It was tactical as well – it gave Marcel Fassler a break from seeing the back of the Porsche he was chasing – but also pumped him right up to go back and out and fight again.

Because we’ve had so much experience at Le Mans and in our preparations for it, I know we’ve not left any stone unturned when it comes to reliability and in terms of pace it is going to be close with Porsche and Toyota, but one of the really great things about this race is that anything can happen, it’s never over until it’s over.