1955 24 Hours of Le Mans

The 1955 24 Hours of Le Mans was the 23rd running of the event and took place on 11 and 12 June 1955 on the Circuit de la Sarthe. It was also the fourth round of the FIA World Sports Car Championship. During the race, a crash killed driver Pierre Levegh and at least 81 spectators while injuring at least 120 others, making it the deadliest accident in motor racing history. The race was won by Mike Hawthorn and Ivor Bueb in a Jaguar D-Type, completing a record 306 laps over a total distance of 4,135.38 km (2,569.73 miles) at an average speed of 172.31 km/h (107.07 mph).

The Automobile Club de l'Ouest (ACO) increased the replenishment window for fuel, oil and water from 30 to 32 laps — just over 430 km — and increased the maximum fuel allowance for all cars to 200 L (44 imp gal; 53 US gal). Road improvements continued with the entire back section of the track, from Tertre Rouge around to Maison Blanche, being resurfaced.

A total of 87 racing cars were registered, of which 70 arrived for practice to qualify for the 60 starting grid places, including 15 factory teams.

Ferrari arrived with the new 735 LM, powered by a straight-six engine derived from the previous year's Formula 1 car, producing 360 bhp (270 kW). The works team included Eugenio Castellotti with Paolo Marzotto, Maurice Trintignant with Harry Schell, and Umberto Maglioli with Phil Hill. Two 3-litre 750 Monzas were run by French private entries.

Mercedes-Benz, having conquered Formula 1 in 1954, entered modified 300 SLR sports cars with a fuel-injected 3-litre straight-8 producing 300 bhp later in the season. To compensate for questionable drum brakes, a hand-operated air brake was fitted to the rear deck. Team manager Alfred Neubauer assembled a multi-national crew: Juan Manuel Fangio and Stirling Moss in the lead car, Karl Kling with Andre Simon, and John Fitch with Levegh. Hans Herrmann had been injured in Monaco practice and was replaced by Simon.

Jaguar fielded three works D-Types with engine power increased from 250 to 270 bhp and a top speed of almost 280 km/h (170 mph). Pairings were Tony Rolt and Duncan Hamilton; Hawthorn with Bueb; and Norman Dewis with Don Beauman. Additional D-Types were entered by Ecurie Francorchamps from Belgium and by American Briggs Cunningham. Cunningham also brought a new Cunningham C6-R using an Indianapolis-style Offenhauser 3.0L straight-4, driven by Cunningham and Sherwood Johnston.

Maserati entered a pair of 3.0L 300Ss and a smaller A6GCS in the S-2000 class. Aston Martin entered three DB3S cars with disc brakes and a 225 bhp (168 kW) 3-litre engine, plus a 4.5L V12 Lagonda. Their drivers included Peter Collins and Paul Frere, Peter Walker and Roy Salvadori, and rookies Tony Brooks and John Riseley-Prichard. Gordini brought a 3-litre T24S for Jean Behra and Elie Bayol. Porsche arrived with four cars in the S-1500 and two in the S-1100 classes, giving a first Le Mans drive to Olivier Gendebien in the Belgian-entered car. Colin Chapman arrived with his new Lotus 9 sports car, and Austin-Healey returned with a single 100S prototype.

Castellotti set the fastest official time in practice, breaking the lap record. During practice, several accidents occurred. Jean Behra suffered face and leg injuries. Elie Bayol rolled his Gordini T24S after swerving for spectators crossing the track, suffering a fractured skull and broken vertebrae. Levegh commented after a close brush: "We have to get some sort of signal system working. Our cars go too fast." Neubauer unsuccessfully asked the ACO to permit a small signalling tower for his team.

The honorary starter was Conte Aymo Maggi, President and organiser of the Mille Miglia. Castellotti led the opening lap, with Hawthorn close behind. Fangio's start was delayed when his trouser leg snagged on the gear shift lever, but he worked up to join them. By lap 4, the three manufacturers' works cars filled the top 8 places. After 70 minutes Castellotti's braking error at Mulsanne let Hawthorn and Fangio through; the lap record was broken ten times in the first two hours, with Hawthorn claiming it on lap 28 over 7 seconds faster than Ferrari's practice lap.

At 6:20 pm at the end of lap 35, having received the signal to pit, Hawthorn braked sharply in front of Lance Macklin's Austin-Healey. Macklin braked hard and veered off the right edge of the track, then back to centre, into the path of Levegh's Mercedes-Benz, which was travelling at 150 mph and running sixth. Levegh's right-front wheel rode up onto the left rear corner of Macklin's car, launching the Mercedes into the air; it rolled end over end for 80 metres over spectators, slammed into a four-foot earthen embankment, and disintegrated. The engine, radiator and front suspension carried into the crowd for almost 100 metres. The car's magnesium-alloy body burned with exceptional heat. Levegh was killed instantly. Race officials kept the race running, reasoning that a mass exit by the crowd would block roads needed by emergency crews.

Phil Hill, driving his first-ever Ferrari racing lap of Le Mans, described seeing Moss pass him in the Mercedes 300 SLR shortly after the crash as a lesson he never forgot.

With Hawthorn handing over to Bueb and Fangio to Moss, the Mercedes team extended its lead. At midnight, Fangio/Moss led Hawthorn/Bueb by two laps, with the Kling/Simon Mercedes and the other works Jaguars scrapping two laps further back. Fitch urged Neubauer to withdraw; Neubauer had already reached the same conclusion but required approval from company directors in Stuttgart. He received the call just before midnight. Waiting until 1:45 am, when many spectators had left, he withdrew his cars, which at that point were running first and third. Chief engineer Rudolf Uhlenhaut went to the Jaguar pits to ask whether Jaguar would respond in kind; Jaguar team manager Lofty England declined.

Don Beauman had spent over an hour extricating his Jaguar from a sandtrap at Arnage; he had just done so when Chapman struck the car. Chapman was disqualified for restarting without a marshal's permission. The Aston Martins had been running to a strict lap-time set by team manager John Wyer; two were sidelined by mechanical issues either side of midnight. The last Ferrari, shared by Trintignant and Schell, retired with engine trouble. The Maserati retired just after midnight with ignition failure.

The race finished in drizzle. Bueb handed the leading Jaguar to Hawthorn for the final 15 minutes. They won by five laps over the Aston Martin of Collins and Frere, Aston Martin's best result since 1951. The podium was completed by Johnny Claes and Jacques Swaters in their yellow Ecurie Francorchamps Jaguar D-Type, 11 laps behind the winners. Porsche achieved its best result to date with the trio of Porsche 550 Spyders finishing fourth, fifth and sixth; Helmut Polensky and Richard von Frankenberg won the S-1500 class, the Index of Performance, and the Biennial Cup. The three-car Bristol team finished seventh, eighth and ninth. The Cunningham retired having never been in contention. The only Italian car to finish was the 1.5L OSCA. Bristol managing director Sir George White donated the team's winnings to a charity for the disaster's victims.

The catastrophic crash remains the deadliest accident in the history of motorsport. The death toll is cited at from 80 to 84 including Levegh, with many more severely injured. The next World Sports Car Championship round at the Nurburgring was cancelled, as was the Carrera Panamericana. Auto racing was banned in many countries. Mercedes-Benz, MG and Bristol withdrew from racing by the end of the season. Phil Walters, Sherwood Johnston, and Fitch retired from racing; Fitch was later coaxed back by Cunningham for the Chevrolet Corvette effort at Le Mans in 1960 and subsequently worked to develop the sand-filled "Fitch barrels" traffic safety device. Less than three months after the race, Lance Macklin retired following a twin fatality accident during the 1955 RAC Tourist Trophy race at Dundrod Circuit. Juan Manuel Fangio never raced at Le Mans again.

The official enquiry concluded no single driver was to blame and cited a tragic combination of circumstances including serious deficiencies in track design and safety. A full ban on motor racing was imposed by the French government and lifted on 14 September 1955, when new regulations were released. The ACO announced its intent to hold the race in 1956, and before that event the grandstands and pits were demolished, the track widened and straightened at the pits, Dunlop Curve realigned, and a wide ditch added between road and spectators. Track safety technology evolved slowly until Jackie Stewart organised a concerted safety campaign a decade later, gaining momentum after the deaths of Lorenzo Bandini and Jim Clark.

This article is based solely on the supplied corpus. No external sources were consulted; claims that could not be substantiated against the corpus were omitted under the drop-the-claim rule.