The 1955 Le Mans disaster occurred during the 24 Hours of Le Mans motor race at Circuit de la Sarthe in Le Mans, France on 11 June 1955. A major crash caused large fragments of debris to fly into the crowd, killing 83 spectators and French driver Pierre Bouillin (who raced under the name Pierre Levegh) and injuring nearly 180 more. It was the most catastrophic crash in motorsport history, and it prompted Mercedes-Benz to retire from motor racing until 1989.

The crash started when Jaguar driver Mike Hawthorn cut in front of Austin-Healey driver Lance Macklin to reach his pit stop, prompting Macklin to swerve into the path of Levegh, who was passing on the left in his much faster Elektron magnesium-alloy bodied Mercedes-Benz 300 SLR. Levegh rear ended Macklin at high speed, overriding Macklin's car and launching his own car through the air. Levegh struck a protective dirt berm at 200 km/h (125 mph), disintegrating and igniting his car, throwing him onto the track where he was instantly killed, and sending large pieces of flaming debris cartwheeling over the berm and into the packed grandstand—including the engine block and hood.

There was much debate over blame. The official inquiry held none of the drivers specifically responsible and criticised the layout of the 30 year-old track, which had not been designed for cars of this speed.

Before the crash

There was great anticipation for the race, as Ferrari, Jaguar, and Mercedes-Benz had all won the race recently and they all arrived with new and improved cars. The Ferraris, current champions at the time, were very fast, but fragile. Jaguar concentrated their racing almost exclusively on Le Mans and had a very experienced driver line-up including Formula 1 (F1) Ferrari driver, Mike Hawthorn.

After conquering F1, Mercedes-Benz had debuted its new 300 SLR in that year's World Championship, including a record-setting win at the Mille Miglia for Stirling Moss. The 300 SLR featured a body made of an ultra-lightweight magnesium alloy called Elektron. The car lacked the more effective state-of-the-art disc brakes featured on the rival Jaguar D-Type, instead incorporating a large air brake behind the driver that could be raised to increase drag and slow the car.

Team manager Alfred Neubauer assembled a multi-national team for the race: pairing his two best drivers Juan Manuel Fangio and Stirling Moss in the lead car, 1952 race-winner Karl Kling with Frenchman André Simon (both also in the current F1 team) and American John Fitch with one of the elder statesmen of French motor-racing Pierre Levegh. It had been Levegh's unprecedented solo drive in the 1952 race that failed in the last hour, which allowed Mercedes-Benz their first Le Mans victory.

Safety measures nearly universal by the year 2000 were relatively unknown in 1955. Aside from two layout changes to make the circuit shorter, the Le Mans circuit was largely unaltered since the inception of the race in 1923, when top speeds of cars were typically in the region of 100 km/h (60 mph). By 1955, top speeds for the leading cars were over 270 km/h (170 mph). That said, the circuit had been resurfaced and widened post-war. The pits and grandstands had been reconstructed, but there were no barriers between the pit lane and the racing line, and only a 4 ft (1.2 m) earthen bank between the track and the spectators. The cars had no seat belts; the drivers reasoned that it was preferable to be thrown clear in a collision rather than be crushed or trapped in a burning car.

The 1955 race began at 4 pm on Saturday, and, as predicted, the lead cars of Eugenio Castellotti (Ferrari), Hawthorn (Jaguar), and Fangio (Mercedes-Benz) were at the head of the field in the first hour. The other team cars were being kept on tighter leashes to conserve the cars, but still racing in the top ten. Going into the second hour, Castellotti started dropping back, but Hawthorn and Fangio continued the duel, swapping the lead and dropping the lap record further and further, lapping most of the field.

The accident happened at 6:26 pm, at the end of lap 35, when the first pit stops for the leading cars were starting.

Crash

On lap 35, Hawthorn and Fangio were racing as hard as ever. In his biography, Hawthorn said he was "momentarily mesmerized by the legend of the Mercedes superiority... Then I came to my senses and thought ‘Damn it, why should a German car beat a British car.'" The lap before, Hawthorn's pit crew had signaled for him to come in the next lap. He had just lapped Levegh (running 6th) after Arnage (one of the corners of the race track) and was determined to keep Fangio at bay as long as possible. Coming out of the Maison Blanche portion of the course, he rapidly caught Lance Macklin in his Austin Healey 100S, who had seen him and moved over to the right to let him pass. Putting another lap on Macklin coming up to the main straight, Hawthorn then raised his hand to indicate he was pitting and pulled across to the right (from Hawthorn's testimony). What caught Macklin out though was that Hawthorn, using his advanced disc brakes, braked very hard to be able to slow the Jaguar from such a speed in time.

There are two key points to the track layout here – first, there was no designated deceleration lane for cars coming into the pits, and second, that just before the main straight, there was the slightest right-hand kink in the road just after where Hawthorn started braking.

Macklin, who also braked hard, ran off the right-hand edge of the track, throwing up dust. Macklin tried to avoid Hawthorn, whether it was an instinctive swerve from surprise, or a loss of control from going onto the change of road-surface, or his car's disc brakes operating unevenly. As a result, Macklin's car veered across to the centre of the track, apparently briefly out of control. This however put him into the path of Levegh's Mercedes-Benz, closing at over 200 km/h (120 mph), intent on doing another lap and in front of Fangio, who was patiently waiting to pass. Levegh did not have time to react, but with possibly his last action, raised his hand warning Fangio, thereby probably saving Fangio's life. Fangio, with his eyes shut, but with his own quick reflexes, squeezed through the carnage, just brushing Hawthorn's now-stationary Jaguar in the pits, but getting through unscathed.

Levegh's right-front wheel rode up onto the left rear corner of Macklin's car, which acted as a ramp and launched Levegh's car into the air, flying over spectators and rolling end over end for 80 metres (260 ft). Levegh was thrown free of the tumbling car, but his skull was fatally crushed when he hit the ground.

That critical kink in the road put the car on a direct trajectory toward the packed terraces and grandstand. The car landed on the earthen embankment between the spectators and the track, bounced, then slammed into a concrete stairwell structure, and disintegrated. The momentum of the heaviest components of the car – the engine, radiator, and front suspension – hurtled straight on into the crowd for almost 100 metres (330 ft), crushing all in their path. The bonnet lid scythed through the air, "decapitating tightly jammed spectators like a guillotine." Spectators who had climbed onto ladders and scaffolding to get a better view of the track, and those crowding to use the underpass to get to the pits, found themselves in the path of the lethal debris.[3]

Jaguar driver Duncan Hamilton, watching from the pit wall, recalled, "The scene on the other side of the road was indescribable. The dead and dying were everywhere; the cries of pain, anguish, and despair screamed catastrophe. I stood as if in a dream, too horrified to even think."

When the rest of the car landed on the embankment, the rear-mounted fuel tank exploded. The fuel fire raised the temperature of the remaining Elektron bodywork past its ignition temperature, which was lower than that of other metal alloys due to its high magnesium content. The alloy burst into white-hot flames, showering the track and crowd with magnesium embers, made worse by rescue workers totally unfamiliar with magnesium fires, pouring water onto the inferno, greatly intensifying the fire: see flammability of magnesium. As a result, the car burned for several hours.

Meanwhile, Macklin's car, heavily damaged, rammed the left-side barrier, then veered to the right of the track into the pit lane, narrowly missing Kling's Mercedes-Benz, Roberto Mieres's Maserati, and Don Beauman's Jaguar, all of whom were already in the pits refueling before the accident. Macklin's car hit the unprotected pit-wall, just short of the Cunningham and Mercedes-Benz pits where Shell and Lockheed equipment were stationed, running down a policeman, a photographer and two officials (all seriously injured), then rebounded back across the track again to end up skating down the left-side fence for a second time. Macklin survived the incident without serious injury, jumping out of the wreck and over the bank.

Following hours

Hawthorn had overshot his pits and stopped. Getting out he was immediately ordered by his team to get back in and do another lap to get away from the total confusion and danger. When he pit stopped during the next lap he staggered out of the car completely distraught, adamant that he had caused the catastrophe. Ivor Bueb and Norman Dewis, both Le Mans debutants, had to step into their respective cars for their first driver stints. Bueb in particular was very reluctant, but given Hawthorn's condition had no choice, as Dewis adamantly pointed out to him.

Everyone expected the race to be red-flagged and stopped. Given the scale of the disaster, however, the race officials kept the race running because, if the huge audience crowd had tried to leave en masse, they would have choked the main roads around, severely impeding access for medical and emergency crews trying to save the injured.

Levegh's co-driver, American John Fitch, was suited up ready to take over the car at the upcoming pit-stop and was standing with Levegh's wife Denise Bouillin. They saw the whole catastrophe unfold. Levegh's lifeless body, severely burned, lay in full view on the pavement until a gendarme hauled down a banner to cover it. His wife was inconsolable and Fitch stayed with her until she could be comforted. Half an hour after the crash he realised that news was probably being broadcast on the radio, and he needed to telephone his family to reassure them that he was not the driver of the crashed car. When he got to the media centre to use a telephone, he got his first inkling of the sheer enormity of the disaster, overhearing a reporter filing that 48 deaths were already confirmed.

When Fitch returned to his pit he urged the Mercedes-Benz team to withdraw from the race, he could see that win or lose would be a public relations disaster for Mercedes-Benz. Mercedes-Benz team manager Alfred Neubauer had already reached the same conclusion, but did not have the authority to make such a decision. After an emergency meeting and vote of the company directors by telephone in Stuttgart, Neubauer finally got the call approving the team's withdrawal just before midnight. Waiting until 1:45 am, when many spectators had left, he stepped onto the track and quietly called his cars into the pits, at the time running first and third. Their retirement was briefly announced over the public address system. The Mercedes-Benz trucks were packed up and gone by morning. Chief engineer Rudolf Uhlenhaut had gone to the Jaguar pits to ask if the Jaguar team would respond in kind, out of respect for the crash victims. Jaguar team manager "Lofty" England declined.

Mike Hawthorn and the Jaguar team kept racing. With the Mercedes-Benz team withdrawn and the Ferraris all broken, Jaguar's main competition had gone. Hawthorn and Bueb won the race by an easy margin of five laps from Aston Martin. The weather had closed in on Sunday morning and there was no victory celebration. However, an inopportune press photograph showed Hawthorn smiling on the podium swigging from the victor's bottle of champagne. The French magazine L'Auto-Journal published it with the sarcastic caption, "A votre santé, Monsieur Hawthorn!" (In English, "To your health, Mr. Hawthorn!")

Accounts put the death toll at 80 to 84 (spectators plus Levegh), either by flying debris or from the fire, with a further 120 to 178 injured. Other observers estimated the toll to be much higher. It has remained the most catastrophic crash in motorsport history. A special mass was held in the morning in the Le Mans Cathedral for the first funerals of the victims.

The death toll led to an immediate temporary ban on motorsports in France, Spain, Switzerland, Germany, and other nations, until the racetracks could be brought to a higher safety standard. In the United States, the American Automobile Association (AAA) dissolved their Contest Board that had been the primary sanctioning body for motorsport in the U.S. (including the Indianapolis 500) since 1904. It decided that auto racing detracted from its primary goals, and the United States Automobile Club was formed to take over the race sanctioning and officiating.

Most countries lifted their racing bans over the next year. However Switzerland's ban, which also extended to the running of timed motorsports such as hillclimbs, was not. This forced Swiss racing promoters to organize circuit events in foreign countries including France, Italy, and Germany. In 2003, the Federal Assembly of Switzerland started a lengthy discussion about whether this ban should be lifted. The discussion focused on traffic policy and environmental questions rather than on safety. On 10 June 2009, the Ständerat (upper house of the Swiss parliament) defeated a proposal to lift the ban for the second time. In 2015, the ban was relaxed for electric vehicles only, such as cars involved in Formula E electric racing.

The next round of the World Sports Car Championship at the Nürburgring was cancelled, as was the non-championship Carrera Panamericana. The rest of the 1955 World Sportscar Championship season was completed, with the remaining two races at the British RAC Tourist Trophy and the Italian Targa Florio, although they were not run until September and October, several months after the catastrophe. Mercedes-Benz won both of these events, and was able to secure the constructors championship for the season. Having achieved that, Mercedes-Benz withdrew from motorsport. The horror of the crash caused some drivers present, including Americans Phil Walters (who had been offered a drive with Ferrari for the rest of the season,) Sherwood Johnston, and John Fitch (after completing the season with Mercedes-Benz), to retire from racing. Lance Macklin also decided to retire after being involved in another fatal crash, during the 1955 RAC Tourist Trophy race at Dundrod Circuit. Fangio never raced at Le Mans again. At Le Mans, the audience stands at the pits were demolished.

Much recrimination was directed at Hawthorn, saying that he had suddenly cut in front of Macklin and slammed on the brakes near the entrance to the pits, forcing Macklin to take desperate evasive action into the path of Levegh. This became the semi-official pronouncement of the Mercedes-Benz team and Macklin's story. The Jaguar team in turn questioned the fitness and competence of Macklin and Levegh as drivers. The first media accounts were wildly inaccurate, as shown by subsequent analysis of photographic evidence conducted by Road & Track editor (and 1955 second-place finisher) Paul Frère, in 1975.[23] Additional details emerged when the stills reviewed by Frère were converted to video form.

The media also speculated on the violent fire that engulfed the wreck, that intensified when fire marshals poured their water-based extinguishers on the flames. They suggested that Mercedes-Benz had tampered with the official fuel-supply with an explosive additive, but the intensity of the fire was due instead to the magnesium-alloy construction of the chassis. Neubauer got the French authorities to test residual fuel left in the wreck's fuel injection and the result vindicated the company.

Opinions differed widely amongst the other drivers as to who was directly to blame for the crash, and such differences remain even today. Macklin claimed that Hawthorn's move to the pits was sudden, causing an emergency that led him to swerve into Levegh's path. Years later Fitch claimed, based on his own recollection and from what he heard from others, that Hawthorn had caused it. Norman Dewis ventured the opinions that Macklin's move around Hawthorn was careless and that Levegh was not competent to meet the demands of driving at the speeds the 300SLR was capable of. Both Jaguar and Mercedes-Benz issued official statements, mainly in self-defense against the accusations leveled against them and their drivers. Neubauer limited himself to suggesting improvements to the pit straight and making pit-stops safer.

Macklin, on reading Hawthorn's 1958 autobiography, Challenge Me the Race, was embittered when he found that Hawthorn now disclaimed all responsibility for the crash without identifying who had caused it. With Levegh dead, Macklin presumed that Hawthorn's implication was that he (Macklin) had been responsible, and he began a libel action. The action was still unresolved when Hawthorn was killed in a non-racing crash on the Guildford bypass in 1959, ironically when overtaking a Mercedes-Benz in his Jaguar.

The official government inquiry into the accident called officials, drivers, and team personnel to be questioned and give evidence. The wreckage was examined and tested and, finally, returned to Mercedes-Benz nearly 12 months after the catastrophe.[23] In the end the enquiry ruled that no specific driver was responsible for the crash, and that it was merely a terrible racing incident. The death of the spectators was blamed on inadequate safety standards for the track design. Tony Rolt and other drivers had been raising concerns about the pit straight since 1953.

Over the next year, the Automobile Club de l'Ouest (ACO) set about making extensive track improvements and infrastructure changes—the pit straight was redesigned and widened to remove the kink just before the start-finish line, and to give room for a deceleration lane. The pits complex was pulled down and rebuilt, giving more room to the teams, but thereby limiting spaces to only 52 starters rather than the previous 60. The grandstand was demolished and rebuilt with new spectator terraces and a wide ditch between them and the racetrack. Track safety technology and practices evolved slowly until Formula 1 driver Jackie Stewart organized a campaign to advocate for better safety measures ten years later. Stewart's campaign gained momentum after the deaths of Lorenzo Bandini and Jim Clark.

John Fitch became a major safety advocate and began active development of safer road cars and racing circuits. He invented traffic safety devices currently in use on highways, including the sand-and-air filled Fitch barrels.

Macklin's Austin-Healey 100 was sold to several private buyers before appearing on the public auction block. In 1969, it was bought for £155. In December 2011, the car was sold at auction for £843,000. The car retained the original engine SPL 261-BN and was valued at £800,000 before the auction. Its condition was reported to be 'barn find'.