Mercedes-Benz CLR

In 1996 Mercedes-Benz's motorsports programmes included support for cars in Formula One, IndyCar, and the International Touring Car Championship (ITC). Following the collapse of the ITC at the end of the 1996 season, Mercedes' attention shifted to a new international series, the FIA GT Championship. Racing partners AMG were tasked with developing a design to meet the Fédération Internationale de l'Automobile's GT1 regulations for the new championship. The new cars, known as CLK GTRs, were designed for use both as racing and road cars available to the public, as series regulations required the racing cars to be based on production models. The CLK GTRs were successful in their debut season, winning seven of eleven races and earning both the drivers' and teams' championships. For the 1998 season AMG refined the CLK GTR's design with the launch of the new CLK LM. A major change for the new design was the replacement of the CLK GTR's V12 engine with a smaller V8, thought by Mercedes to be more suitable to take on longer endurance events such as the 24 Hours of Le Mans, a race not part of the FIA GT calendar. Despite earning pole position for Le Mans, the new cars were unreliable and both lasted less than three hours before retiring with mechanical failure. The race was won by Mercedes' FIA GT rivals Porsche. Mercedes did go on to win its second straight FIA GT Championships later that year after winning all ten races. After the dominance of Mercedes, most of the GT1 class competitors chose to not return to the FIA GT Championship for 1999, leading the FIA to eliminate the category from the series. The Automobile Club de l'Ouest (ACO), organisers of the 24 Hours of Le Mans, chose to follow the FIA's lead and no longer allow GT1 category cars to enter Le Mans. While FIA GT concentrated solely on its lower GT2 category in 1999, the ACO created a new category of race car known as a Le Mans Grand Touring Prototype (LMGTP). The LMGTP regulations for closed-cockpit cars were similar to the former GT1 regulations but shared many elements with the ACO's existing open-cockpit Le Mans Prototype (LMP) category. Mercedes, no longer able to compete in the FIA GT Championship with the CLK LMs, chose to concentrate on the ACO's new LMGTP category. ==Development==

Work on designing a new car to meet LMGTP regulations began in September 1998 as Mercedes was closing out its second FIA GT Championship season. Development was led by HWA GmbH, the motorsports division of AMG, which became an independent company the following year. The LMGTP rules did not require road versions of the cars to be built, so Gerhard Ungar, chief designer for HWA, Mercedes publicly announced its CLR programme in February 1999 just days before the first car began private testing at California Speedway in the United States. Testing continued into March at California as well as Homestead-Miami Speedway in Florida before the team moved to the Circuit de Nevers Magny-Cours in France. At Magny-Cours three CLRs completed a 30-hour test session covering . On 20 April the CLR was shown to the press for the first time during a test session at the Hockenheimring in Germany. By that point in the development process the CLRs had covered in testing without any major failures. ==Preparation==

The initial schedule for the CLRs consisted of participation in the May pre-qualifying and testing session at Le Mans in preparation for the race in June. At the team's Hockenheim test session plans were announced to enter several races after Le Mans. The first, scheduled for July, was to be an exhibition event consisting of two races at the Norisring street circuit in Nuremberg, Germany. Mercedes planned to enter four CLRs in the event. The team would then end its season with the final three races of the American Le Mans Series: the 10-hour Petit Le Mans endurance at Road Atlanta and shorter races at Laguna Seca Raceway and Las Vegas Motor Speedway. More than 200 personnel from Mercedes-Benz and HWA formed the crew for the three cars although the team was officially known as AMG-Mercedes. Former Macau Grand Prix winner and All-Japan Formula Three champion Peter Dumbreck also came from an open wheel racing background. Pedro Lamy, 1998 FIA GT2 Champion, was drafted from the Oreca Chrysler team to participate at Le Mans and in the Deutsche Tourewagen Masters for Mercedes, while Franck Lagorce transferred from Nissan's Le Mans squad. Darren Turner, also a test driver for McLaren, served as the team's reserve driver for Le Mans. ==Le Mans==

Practice and qualifying By winning the 1998 FIA GT Championship, Mercedes were awarded a single guaranteed entry for Le Mans, which was assigned to Gounon, Tiemann, and Webber in CLR No. 4. Bouchut, Dumbreck, and Heidfeld in the No. 5 and Lagorce, Lamy, and Schneider in the No. 6 entries would have to pre-qualify for the event, while No. 4 was free to use the pre-qualifying session for testing purposes. Early in the second day of sessions, Webber, driving CLR No. 4, was following the Audi R8R of Frank Biela through the portion of the circuit connecting Mulsanne Corner and the Indianapolis complex when he moved out of the Audi's slipstream to overtake. The CLR suddenly lifted its nose and front wheels off the circuit and became airborne, flipping upwards and somersaulting backwards before rotating onto its side. The car impacted the tarmac with its right side while perpendicular to the circuit then flipped back onto its wheels before skidding into the safety barriers on the side of the circuit. :: Webber's qualifying accident: Webber's warm-up accident: Dumbreck's race accident Due to the accident, the No. 4 car was unable to improve its qualifying time from the previous day, which relegated the car to tenth on the starting grid as competitors improved their times; Mercedes No. 5 also did not improve its lap time and finished the session seventh. Bernd Schneider was able to go quicker than his time from the previous day with a 3:31.541 lap for the No. 6 car. Toyota took pole position with a 3:29.930 lap, while Schneider's car was placed fourth on the final starting grid. The wreckage of the CLR No. 4 was returned to Mercedes at the end of the qualifying session and the team issued a press release confirming that they could repair the car before the start of the race two days later. Photographers in the same location also captured the car as it flipped. The ACO later published these photographs in its 1999 yearbook. Norbert Haug, head of Mercedes-Benz's motorsport activities, contacted Adrian Newey, chief aerodynamicist of the McLaren Formula One team, for consultation on modifying the remaining CLRs to prevent further accidents. The drivers were also consulted on whether they believed the cars were too dangerous to race; Bouchut felt that the front of the car could become light at high speeds and voiced his concerns to the team, but other drivers had not felt this issue with the cars. One of the Toyotas eventually suffered transmission issues which dropped it down in the field, leaving the top six positions to be swapped amongst the two remaining Toyotas, two Mercedes, and two BMWs as they made pit stops on different schedules. Driver changes during later pit stops had Lagorce getting in the No. 6 to replace Schneider, while Dumbreck replaced Bouchut in the No. 5. Schneider reported that, despite some initial problems dealing with the car's new aerodynamics, it was running well by the end of his stint. Towards the close of the fourth hour of the race, Dumbreck's Mercedes came into contact with the GTS-class Porsche 911 GT2 of the Estoril Racing team at the Ford Chicanes, but continued with no apparent damage. On lap 76 Dumbreck was in third place and catching Thierry Boutsen's Toyota in second place. The Mercedes and Toyota were nose to tail on the run from Mulsannes Corner to Indianapolis at nearly with both drivers partially blinded by the setting sun ahead of them. At a slight right kink in the straight, Dumbreck's CLR ran over the small apex kerbing and suddenly lifted its front wheels from the ground before somersaulting backwards as the entire car became airborne. Dumbreck was knocked unconscious after the initial impact At the end of the 76th lap Lagorce was ordered by the team to bring the remaining CLR directly to its garage; upon the car's arrival AMG-Mercedes shut the last of its three garage doors signifying its official retirement from the event. National rivals BMW went on to win the race the following day. ==Aftermath==

Following the race the ACO and the Fédération Française du Sport Automobile (FFSA) national motorsport body investigated the incidents. The FFSA questioned the ACO's decision to allow Mercedes to continue to compete after the two accidents prior to the race start, but the ACO argued that there were no indications that the problems that befell CLR No. 4 were shared by the other Mercedes entries. The ACO argued that the design of the CLR, with the longest front and rear overhang amongst the prototype field, was the cause of the problem. Already in 1998, at Road Atlanta in the United States, the Porsche 911 GT1-98 of Yannick Dalmas, similar in design to the CLR, had suffered a nearly identical blow over accident when going over a hump, and at the very same place in 2000, the open cockpit BMW V12 of Bill Auberlen also backflipped. The ACO changed the regulations for the LMGTP category in 2000, decreasing the allowable length of overhang. and Audi concentrated on open-cockpit LMP cars; the class reappeared in 2001. Peter Dumbreck, in response to his accident, initially blamed the height of the kerbs he had run on when his car became airborne, but Mercedes-Benz responded by stating that blame did not lie with the circuit. The kerbs, as well as the entire Le Mans circuit, were all approved by the FIA. Before the race had concluded, Mercedes-Benz addressed criticism from other drivers and teams of its decisions. Haug believed that the team's data from Webber's practice incident had been adequately analysed and that the drivers did not feel there were problems with their cars in traffic that could cause the same incidents, prompting his decision to continue. He also stated his belief that contact between CLR No. 5 and the Estoril Porsche may have damaged the front diffuser and led to the aerodynamic instabilities. Shortly after Le Mans, Mercedes conducted its own examination of the accidents by running the remaining CLR on an airfield to verify wind tunnel data. Although no conclusions were published by Mercedes, the company cancelled the rest of its 1999 programme, withdrawing from the Norisring exhibition event and the final three rounds of the American Le Mans Series. Despite the failure of the CLR project, Christophe Bouchut felt that the cars were his favorite to drive in a 21-year career at Le Mans, praising the cars' handling and technology. The car appeared in the hands of a private owner in 2009 at a Modena Trackdays event held at the Nürburgring and was driven on the circuit. Since 2023, the car is on display at the Nationales Automuseum, a German car museum. The failures of the CLRs have become lore for Le Mans and motorsport in general. Speed Channel, as part of its tenth anniversary, named its broadcast of Dumbreck's accident as the fourth most memorable moment in the network's history. Road & Track magazine's list of the ten most infamous crashes at Le Mans named Webber's warm-up accident as seventh and Dumbreck's crash as second. ==See also==