The 1955 24 Hours of Le Mans was the 23rd 24 Hours of Le Mans and took place on 11 and 12 June 1955 on Circuit de la Sarthe. It was also the fourth round of the F.I.A. 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.
Regulations The Automobile Club de l'Ouest (ACO) again lifted the replenishment window (just changed the year before) of fuel, oil and water from 30 to 32 laps — just over — but by the same token, the maximum fuel allowance for all cars was increased to for the race.
On the track, road improvements continued with the whole back section, from Tertre Rouge around to Maison Blanche, resurfaced.Spurring 2011, p.214Moity 1974, p.60
Entries A total of 87 racing cars were registered for this event, of which 70 arrived for practice, to qualify for the 60 places on the starting grid, and included 15 factory teams.Spurring 2011, p.215
Category Classes Entries Large-engines S-5000 / S-300026 +1 reserve Medium-engines S-2000 / S-1500 17 +7 reserves Small-engines S-1100 / S-750 17 +4 reserves
The battle between Coventry and Maranello of the previous year was joined by Mercedes-Benz, fresh from a triumphant 1-2 debut win in the Mille Miglia with their new 300 SLR backed up with a 1-2 Eifelrennen win at the Nürburgring, along with dark horses Cunningham, Aston Martin and Maserati, all with new 3-litre cars, as well as Talbot, Gordini, Cooper, and Austin-Healey. It led observers to anticipate a great contest.
Title-holders Ferrari arrived with the new 735 LM, powered by a straight-six engine derived from the previous year's Formula 1 car (and stepping away from the usual 12-cylinder Ferrari engines) producing a .Laban 2001, p.116 The works team mixed its current F1 drivers along with new talent: Eugenio Castellotti with Paolo Marzotto, Maurice Trintignant with Harry Schell and Umberto Maglioli drove with Phil Hill. Maglioli and Hill had been Ferrari rivals in the previous Carrera Panamericana.Cannell 2011, p.65 There were also two 3-litre 750 Monzas run by French private entries.
The original Mercedes-Benz 300 SL Gullwing (W194) had succeeded already in 1952 in international sports car racing, including Le Mans 24h and the Carrera Panamericana, but it came a year too soon for the first World Sportscar Championship. In the 1954 Formula One season1, Mercedes-Benz missed two rounds and debuted only in July. Despite entering three or four cars, team manager (Rennleiter) Alfred Neubauer had only one winning driver under contract, Juan Manuel Fangio, who already had been at the wheel of Silver Arrows in early 1951, when Mercedes was running pre-war cars at Argentinian Formula Libre races like the 1951 Buenos Aires GP. Sports car endurance racing required even more resources, and mostly two drivers per car, thus a return was postponed to the 1955 WSC season despite having the car already in 1954: the 300 SLR (W196S), which only shared name and engine capacity of 3.0 litre with the original carburetted 1952 300 SL, and with the fuel injected 300 SL Gullwing (W198) that already was on sale in 1954. The Mercedes-Benz W196 had been developed in two variants: for F1, a single seater with aerodynamic closed-wheel aluminium "Type Monza" streamliner body was made, and concurrently a two-seat sports car coupé, again with Gullwing doors, as the 1952 300 SL mostly had been raced as low drag closed coupe, except at the Nürburgring, where all cars were open. The road car had the trademark Gullwing doors, too, but only until 1957. Both early W196 variants had too much sheet metal, as the defeat at the 1954 British GP showed that a proper open wheeler was needed, and drivers asked for an open top sports car which already was tested in public in September 1954 at Monza where Fangio won the 1954 Italian GP. More adjustments were needed after the 1954 Spanish GP where the low-mounted air-intake picked up debris, which led to the intake's relocation atop the hood. Mercedes did not show up at the late November 1954 Carrera Panamericana, but young driver Hans Herrmann was allowed to race in a Porsche 550 with just 1500cc and finished 3rd.
The Mercedes factory team was present for the 1955 Argentine Grand Prix, won by Fangio in blistering heat, but inexplicably skipped the 1955 1000 km Buenos Aires, and then Fangio also won the 1955 Buenos Aires Grand Prix Formula Libre race with the 3.0 liter sports car engines mounted in all four F1 chassis. Capacity of the 8-cylinder was enlarged by longer stroke from 2.5 to 3.0 liter, still significantly smaller than competitors. Instead of the toxic special fuel mixture used in F1, it had to run on regular pump gas, with lower compression and lower revs. The fuel-injected 3-litre straight-8 was the most advanced of the entire field, producing later in the season. Mercedes also skipped Sebring to practise in Italy for the 1955 Mille Miglia in which four SLR were entered, two with passengers as the single lap around Northern Italy did not allow the usual pit stops for driver changes. Moss famously used Denis Jenkinson to copy the pace notes principle Mercedes had used at the 1952 Carrera, scoring another win, while Herrmann carried a mechanic to no avail, dropping out with a leaking fuel filler cap.
After two 1-2 wins at the fast Mille and at the twisty Nürburgring, the 300 SLR were rated by many experts as the best sports cars in the world. There was one Achilles' heel the team tried to address already in 1952: braking from the high speeds of Le Mans straights into the slow Mulsanne and Indianapolis corners. An air-brake flap was added to the Gullwing roof, but not permitted by the ACO. Average speeds in 1952 of 173 kp/h (107 mph) went up in 1955 to some 190 kp/h (118mph) in practise and even faster in the race, with Fangio being clocked at 292.21 kp/h (181.57 mph). Jaguar had won in 1953 using new disc brakes that barely faded. The inboard drum brakes of Mercedes, however, were only questionably adequate for the heavier chassis, facing the tough braking demands of Le Mans. To compensate, the now larger hand-operated air brake was added to the rear deck for high speed brakingSpurring 2011, p.221 which was permitted after adding glass-covered viewing ports.
Team manager Alfred Neubauer had already guided Mercedes to the 1952 Le Mans win, but that was rather lucky as the original 300 SL Gullwing in 24h tuning delivered few more horses than the 150 in the two-door luxury sports tourer 300 S it was taken from. Three pre-war heroes and several barely known Germans were to be on the three car team, but only Hermann Lang raced and won after Rudolf Caracciola in Bern and Luigi Fagioli in Monaco suffered severe injuries. Thus Mercedes was all German in 1952, but quite the opposite in 1955. In a remarkably diplomatic move (recalling the war had only ended 10 years earlier), and with more funds, performance and credibility than in 1952, Neubauer assembled a more multi-national and talented team. Four factory pilots had started the year, with Stirling Moss added to Fangio, Kling and Herrmann, but at least six were needed. With Pierre Levegh nearly winning the 1952 race without handing over to a co-driver, Neubauer decided to offer him a future ride, and did so for 1955. American John Fitch already had been on the 1952 Carrera team. In the Mille Miglia, Kling crashed and broke his ribs, preventing him from racing in the 1955 Monaco GP, thus Frenchman André Simon was brought in. When Hans Herrmann got badly injured and was out for the year, Simon filled the gap.John Fitch, "Racing with Mercedes" (Photo Data Research, , 2005) Belgian racing-journalist, class winner and future overall winner Paul Frère had originally been approached but signed to drive for Aston Martin, instead.Moity 1974, p.59 For the 24 hour race, Neubauer paired his two best drivers Fangio and Moss in the lead car to prevent them racing each other. Kling was teamed up with Simon, and Fitch with Levegh.
Jaguar arrived with three works D-types. This year's model had engine power increased from , for a top speed of almost .Spurring 2011, p.219 The team consisted of 1953 winners Tony Rolt and Duncan Hamilton; up-and-coming English star Mike Hawthorn (stolen from Ferrari) paired with rookie Ivor Bueb; and Jaguar test driver Norman Dewis sharing the third car with Don Beauman. They were backed up by D-Types entered by Belgium's Ecurie Francorchamps and from American Briggs Cunningham's team.
Cunningham hedged his bets this year – along with the Jaguar he loaned 750 Monzas to French privateer Michel Pobejersky (racing as "Mike Sparken") and American Masten Gregory. He also brought (for the last time, as it happened) a new Cunningham C6-R, giving up on a big V8 Hemi to instead use an Indianapolis-style Offenhauser 3.0L straight-4.Laban 2001, p.117 He and Sherwood Johnston would race it.
The Maserati team did make it this year – with a pair of their new 3.0L 300Ss, which had already shown promise at Sebring. They were run by the team's regular F1 drivers, one shared by Roberto Mieres and Cesare Perdisa, the other by Luigi Musso and endurance racing veteran Luigi "Gino" Valenzano. Maserati also ran a smaller A6GCS in the S-2000 class.
Louis Rosier's privateer Talbot did not make the start, so the large-engined French challenge this year came from Gordini with a 3-litre T24S for F1 drivers Jean Behra and Élie Bayol. Like Maserati, they also ran a smaller T20S in the S-2000 class.
There was great interest for British fans, aside from the Jaguar team. In total there were 27 British cars starting, nearly half the field.Clausager 1982, p.93 Aston Martin pared back its effort a bit, to just three DB3S (now with disc brakes and an improved 3-litre engineSpurring 2011, p.228). They came with a good driver line-up: Peter Collins and Paul Frère, 1951 winner Peter Walker and Roy Salvadori, and rookies Tony Brooks and John Riseley-Prichard. They also persisted with the Lagonda project – the 4.5L V12 being biggest engine in the field. This year Reg Parnell was co-driven by Dennis Poore.
After boycotting the previous year's race, Austin-Healey returned with a single 100S prototype. Cooper brought two cars – one a Jaguar-engined T38, the other, a T39, with a Climax engine. In the S-2000 class, along with a pair each of Triumph TR2s and Frazer Nash Sebrings, Bristol was back, this time with its 450C open-top variant. To save pit-time, the team also pioneered a multi-barrel spanner to remove and re-apply all the wheelnuts together when changing the wheel.Spurring 2011, p.230 MG returned after 20 years with the EX.182 prototype – a 1.5L forerunner of the upcoming MGA roadster. Colin Chapman, racing with Scotsman Ron Flockhart arrived with his new Lotus 9 sports car – like the other small English firms Kieft, Cooper and Arnott, running the 1100cc Climax engine.Spurring 2011, p.231
After a fortuitous class victory in 1954, Porsche arrived in force with a mix of works and (nominally) private entries: four Porsche 550 spyders in their usual S-1500 class, and two with smaller engines in the S-1100 classes. In contrast, after the despair of their 1954 race, OSCA only had a single privateer in the S-1500 class.
The smallest, S-750, class was again dominated by French cars, from Panhard, Monopole, DB (all with Panhard engines), and VP-Renault. Panhard also fielded two bigger, 850cc-engined, cars that had to run in the S-1100 class. However several Italian teams arrived to take on the French with entries from Moretti and Stanguellini. Perhaps the most unusual entry was the tiny catamaran-style Damolnar Bisiluro from Ufficine Nardi – where the driver sat in one boom and the engine and running gear was in the other.
Practice