24 HOURS CENTENARY – PERPETUAL INNOVATION ⎮ In its 100-year history, the race has consistently served as a testing ground for technological innovation of all kinds, including cars designed specifically for Le Mans like the three-time winning Jaguar Type D.
Jaguar scored its first win at the 24 Hours in 1951 with an XK120 C, commonly referred to as the Type C. But for 1952, the factory team's favourite driver, Stirling Moss, requested the profile of the car be revamped after coveting Mercedes' top speed.
A more aerodynamic version of the Type C took the start in the race that year, but without success: insufficiently cooled engines caused retirements for all three cars fielded. The following year, the Type C returned to centre stage with more conventional bodywork, and above all, game-changing disc brakes. But Jaguar understood a new car was needed to take on Ferrari (whose engine power had only increased at the urging of Enzo Ferrari) and state-of-the-art Mercedes. Enter the Type D for the 1954 24 Hours.
Lighter, faster!
The Type D was lighter and faster than its Type C predecessor. To achieve these initial goals, Jaguar engineers designed a monocoque aluminum alloy structure running fom the front firewall to the rear suspension. At the front of this bulkhead, a subframe was welded to support the engine and front suspension. This design fostered sturdiness and lightness as compared to the 1953 Type C, with the weight decreased from 1,013 kg to 880 kg, a difference of 133 kg.
The second objective was reached thanks to bodywork imagined by aeronautial engineer Malcolm Sayer. Contrary to the standards of the time, the front did not include a grille. A simple vent let air in and cooled the engine, inspired by the one found on the production E-Type. The overall shape of the car was very flat on top between the fenders with an extended bonnet and bulbous lines on the front and sides. The windscreen protected only the driver with the passenger seat sealed off by an added body panel. Behind the driver, a raised area ran from the helmet down toward a very thin rear plane that ended with a simple junction stop between the upper and lower parts.
The engine remained unchanged from the Type C (with the advantage of its robustness and the disadvantage of its long stroke which limited maximum speed): a 3,442 cc six-cylinder, double overhead camshaft, but changed from two to three carburettors, Webers replacing the SUs. The engine delivered more than 250 hp and 325 Nm of torque. Naturally, it retained the extraordinary disc brakes with which the Type C had triumphed the previous year.
The Jaguar Type D first hit the track for preliminary tests in April 1954. But almost immediately, in preparation for the race in June, a dorsal fin was added at the rear with the aim of stabilising the car at high speeds. This shark fin style along with the aerodynamic curves of the bodywork gave the car icon status.
At the perpetually rainy 1954 running of the race, and though outgunning the Ferrari 375 Plus by nearly 80 hp, the car constantly struggled to keep up, even coming up on the same lap following the Italian car's electrical problems during its last stint, and in the end trailed winners Maurice Trintignant and José Froilán González by four kilometres.
1955-1957 | Three wins in a row
The highly anticipated 1955 24 Hours included Mercedes' three cars with an airbrake behind the driver, Ferrari's three and Jaguar's five (three official and one for both Cunningham and Ecurie Francorchamps) and Aston Martin as the underdog.
To measure up to the super-powerful German and Italian cars, Jaguar once again improved the aerodynamics of its Type D with a longer nose, more enveloping windscreen and a rear edge that ran all the way to the end of the car, saving valuable kilometres per hour.
The epic battles were cut short after Mercedes was forced to retire due to Pierre Levegh's accident and Ferrari fell victim to engine failures. The Type D of Mike Hawthorn/Ivor Bueb (#6) claimed the top step on the overall podium for Jaguar's third win.
In 1956, the ACO required windscreens cover the entire width of the cars. The Type D juggled with the regulations by installing a gently sloping panel next to the driver above the passenger seat.
Jaguar clinched a fourth victory thanks to the short-nosed Type D entered by Ecurie Ecosse shared by Ron Flockhart/Ninian Sanderson. The only factory car under the chequered flag finished sixth driven by 1955 winners Mike Hawthorn/Ivor Bueb, the other two having collided on the third lap.
The British marque officially withdrew from competition and entrusted the running of its ex-factory Type Ds to Ecurie Ecosse who in 1957 scored a final win attributed to Flockhart/Bueb. The Type D achieved a stunning quadruple thanks to private teams, adding sixth place to the mix.
And so ended the saga of this exceptional combination of technological intelligence, specialised chassis, elevated bodywork and a traditional 3.5-litre British engine. For the 1958 24 Hours, the ACO limited displacement to 3000 cc and the venerable XK engine could no longer prove competitive by reducing its displacement by 500 cc. The Jaguar Type D remains to this day one of the top legends in the history of Le Mans.
PHOTOS (Copyright - ACO Archives): LE MANS (SARTHE, FRANCE), CIRCUIT DES 24 HEURES, 1955-1957 24 HOURS OF LE MANS. From top to bottom: the winning Type D of Mike Hawthorn/Ivor Bueb at the 1955 running marked both by Pierre Levegh's accident and heavy rains; a change in the regulations led to modifications to the windscreen of the Jaguar Type D, as seen on Johnny Claes/Jacques Swaters' #10 (third in 1955) and Mike Hawthorn (here at the wheel of the #1)/Ivor Bueb's (second in 1956).