For 60 years the two letters "SL" have had a mystical resonance among automotive enthusiasts. They stand for powerful sportiness, exciting design, effortlessly superior style, technical innovations and the ultimate in engineering artistry. The Mercedes-Benz SL-Class inherited these genes from its forefather, designed as a racing car. In 1952 it came to the international race tracks, saw and conquered. It was from this car that Mercedes-Benz derived the first series-production model in 1954, the legendary 300 SL gullwing. And ever since, Mercedes-Benz has been setting the bar high in the luxury sports car segment with the SL over five model generations.

The unique combination of systematic sportiness, refined luxury and yet unrestricted suitability for everyday use at the same time is what makes the Mercedes-Benz SL-Class the dream car it is - and it is also what lies behind its success where sales are concerned. The SL was always ahead of its time technically - even when it was rolling off the production line for 18 years at a time, as was the case with the SL bearing the internal code R107 (from 1971 to 1989). Over 650,000 SL vehicles have left the production halls in Sindelfingen and Bremen since 1954, and from the last model generation alone - which celebrated its premiere in 2001 - nearly 170,000 specimens found their way into the hearts of the enthusiasts amongst fans of high-calibre sports cars.

The new generation of the Mercedes-Benz SL-Class now being presented is the sixth to follow the 1952 racing car. In the unique tradition of the SL it is entering its era as an athlete, refined aesthete and innovative trendsetter with an extraordinarily high utility value. Mercedes-Benz is initially offering the new SL with two engines - as the SL350 with a V6 engine and as the SL500 with a V8. The new BlueDIRECT engines have an output of 225 kW (306 hp) in the SL350 and 320 kW (435 hp) in the SL500 (a 12-percent increase over the predecessor).

Moreover, the new Mercedes-Benz SL-Class breathes new life into the meaning of the famous abbreviation "SL" - super-light - through systematic weight reduction. For the first time ever, Mercedes-Benz is implementing an all-aluminium bodyshell in series production. The newly developed vehicle weights approximately 110 kilograms less than a comparable bodyshell made of sheet steel. Nevertheless it is even more rigid - and safer - than its predecessor. Mercedes-Benz has achieved this through a systematic intelligent material mix of aluminium alloys and aluminium components which are tailor-made for the respective requirements, combined with just a few portions of high-strength steel and magnesium.

Although the new SL is even more comfortable and has more safety devices on board than its predecessor and therefore does actually sacrifice some of the weight saved through the aluminium bodyshell, the scales show some astonishing figures: the new SL500 (1785 kg) weighs around 125 kilograms less than its predecessor. On balance, the SL350 (1685 kg) is even 140 kilograms lighter - all thanks to a host of other intelligent enhanced details to reduce weight, which Mercedes-Benz has also implemented in the new SL in addition to the aluminium bodyshell.

And these measurement results do not just impress as figures on the page; they are very much perceptible and tangible in practice, too. The resulting increase in longitudinal and lateral dynamics facilitates superb performance with a decided passion for cornering. The greater track width at both the front (+ 38 mm) and rear (+ 77 mm) axle serves the handling which is at once sporty and agile and keeps the car under safe control. Drivers will find the new Mercedes-Benz SL-Class even more agile than its predecessor - sheer pleasure for those of a sporty orientation.

There are two suspension variants from which to choose. The SL is supplied as standard with semi-active adjustable damping (lowered by ten millimetres in the AMG sports package). The active suspension system ABC (Active Body Control) is available as an optional extra. Unique the world over, it has been enhanced especially for the new SL.

In keeping with the Mercedes-Benz tradition, the new SL couples its sharpened athletic profile and agile nimbleness with a luxurious ambience. Its high-quality equipment and appointments contribute to the exquisite motoring pleasure that can be experienced every kilometre of the way. Fine materials, finished with great attention to detail, shape its style and character. The levels of comfort here - unique in the segment of luxury sports cars - blend with high everyday practicality, for the new SL shines with top marks where open-top motoring, suspension comfort and comfort on long journeys are

concerned - plus its exemplarily low background noise, which is comparable with that of a saloon. This all adds up to the fact that this vehicle is a Gran Turismo in the very best sense of the word.

The safest and the most sparing

Thanks to the crash-optimised aluminium structure, standard-fit PRE-SAFE® and assistance systems on the same high level as the S-Class, the SL is the world's safest roadster.

What's more, it is the most frugal one in its class. The SL350 consumes 6.9 litres over 100 kilometres, which is virtually 30 percent less than its predecessor (CO2 159 g/km). The SL500, too, posts a persuasive set of efficiency figures: 9.1 litres per 100 kilometres (minus 22%) correspond to 212g/km CO2.

The design, meanwhile, displays all the classic proportions so characteristic of the SL. Right from the first glance the masculine-looking roadster with a broad tail end is immediately identifiable as a member of the current family of sports cars from Mercedes-Benz. It emphasises its autonomy through a multitude of details created with loving care.

The sixth generation of the Mercedes-Benz SL-Class also offers a vario-roof that can be retracted into the boot using an electrohydraulic mechanism to save space, converting the SL into a roadster or a coupé, depending on the driver's wishes and the weather. Unlike its predecessor, three versions are available for the new SL: painted, with a glass roof or with the unique panoramic vario-roof featuring MAGIC SKY CONTROL. The transparent roof switches to light or dark at the push of a button. When light it is virtually transparent, offering an open-air experience even in cold weather. In its dark state the roof provides welcome shade and prevents the interior from heating up in bright sunlight.

With two innovations, the new SL remains true to its tradition as technological trendsetter:

• MAGIC VISION CONTROL is a new intelligent, high-efficiency windscreen wiper/washer system. Its system of channels supplies water to the windscreen just in front of the laser-cut wiper blade lip. As a result, when spraying, there are no gushes of water on the windscreen to disrupt visibility, and yet the windscreen is kept clean.
• Also unique, the Frontbass system uses the free spaces in the aluminium structures in front of the footwell for housing the bass loudspeakers. As a result, the new SL features clear, crisp bass sounds that facilitate a concert hall ambience even with the top down.

Both innovations are part of the extensive standard equipment of the new SL.

Design: Masculine, muscular athlete's physique

The design of every Mercedes-Benz SL has an obligation to a great legend, and yet it is always very clearly looking to the future. The designers have unmistakably showcased the youngest generation of the style-defining roadster on the basis of tradition, but also with new perspectives and visions. This has resulted in a formal identity and the high overall aesthetic quality.

In the interplay between innovation and tradition we have created a stylish, sporty and elegant luxury sports car with the classic, well-balanced hallmark SL proportions: the long bonnet is followed by a compact, set-back passenger compartment. A broad, muscular, racy-looking tail end completes the picture.

Design boss Professor Gorden Wagener: "The athletic, sports star's physique with its masculine, muscular character says a great deal about the new SL and confidently emphasises its status as the high-performance heart of our brand. At the same time, discerning athletic standards are met by powerfully sculpted surfaces formed by just a few lines and beautifully crafted details. The traditional design elements from our rich history are more than visual quotations. They tell of the courage and the pioneering spirit which have shaped our brand, and reflect these properties in a contemporary way - with enthusiasm and passion. Alongside top technical performance and innovations, it is also this which makes the new SL an unmistakable character."

The front signals a self-confident presence

Visually, the new SL is clearly marked out as a prestigious member of the current Mercedes-Benz sports car family. At first glance this is evident from the very upright classic sports car radiator grille which has featured on all the Mercedes-Benz vehicles with a sporty character - right from the initial generation of the SL. The central star in the radiator grille points the way to the future: it is a contemporary reinterpretation of the famous trademark, which now runs into the centrepiece with organically flowing contours.

What's more, on the new roadster the designers have waived the classic

separation of the bumper and the radiator grille. The lower edge of the grille now dips into the bumper, supporting the pronounced V-shape and resulting in more formal presence. In addition to this, the steeply positioned radiator grille lengthens the bonnet in visual terms. Two air outlet grilles, each with two chromed fins, have their roots in Mercedes-Benz's traditional, dynamic design repertoire. A succinctly sculptured edge - developing from the upright radiator grille - draws across the long bonnet in a taut arch and flows organically into the A-pillar.

Dynamically positioned at an angle, headlamps located far on the outside flank the distinctive front and the broad air intake, giving the new roadster its own inimitable look. It appears masculine and it does also radiate a certain restrained aggressiveness.

The standard-specification ILS headlamps are characterised by very high-quality tubes for the low and main beam which have been styled with great attention to detail, plus a chrome bracket surrounding the main headlamp and the flared arrangement of the indicator lamps and sidelights. All the further functions feature LED technology - such as the distinctively curved sidelights and the horizontal band of the daytime running lamps in the outer sections of the bumper.

The silhouette displays muscles with character

A minimal amount of artistically styled lines define the athletic yet smooth surfaces of the flanks. The shoulderline rises from the headlamps and stretches like a tensed muscle over the entire length of the vehicle and into the tail lights. Side grilles with fins in the front wings stylishly cite the classic SL legend and form the starting point for a feature line. This structures the proportions and lends the vehicle a visual forwards thrust even at a standstill. It tapers out in the tail light as a discreet line.

Free-standing exterior mirrors located on the beltline not only support the modern character of the side view; thanks to this position they also improve vision of the road.

Depending on the engine variant, various light-alloy wheels are available in 17-inch and 18-inch versions. The exquisitely bordered wheel arches are designed for a maximum size of 19 inches at the front and 20 inches (only in the case of AMG) at the rear.

Muscular tail end

A small number of sweeping lines shape the broad, clearly defined tail end. Elegantly flowing and at the same time racy and muscular, it forms the roadster's distinguished finishing flourish that is so full of character. Thanks to the boot lid with its steel interior and plastic panelling, it has been possible to stow the aerials out of sight inside the vehicle so that they do not interrupt the flowing lines in the rear area. This is also the case with the roll-over protection, which lies hidden from view in the body and is only activated in case of danger.

Tail lights with LED High Performance technology highlight the width of the tail end. They taper inwards to a point and have a discreet kink in the contour. The rear fog lamp is located centrally between two trapezoidal exhaust tailpipes. A horizontal swage line in the lower area of the bumper provides added emphasis of the broad effect.

The colour range for the exterior encompasses twelve different paints. These include the BRIGHT paint diamond white and the special colour cerussite grey metallic SHAPE - the first matt paint in the standard-specification paint range for a Mercedes-Benz model series.

Interior and appointments: Luxurious comfort and sporty precision

The interior of the new SL impresses with its generous amount of space, high-quality materials, high sense of perceived value and lovingly crafted details displaying tangible and visible precision.

Compared with its predecessor, the new generation of the SL is much longer (+ 50 mm to 4612 mm) and wider (+ 57 mm to 1877 mm), providing more room for more comfort in the interior, too. Shoulder room (+ 37 mm) and elbow room (+ 28 mm) have been increased, exceeding the dimensions normally found in this vehicle class. Clear lines create a formally coherent internal space within this comfortable interior. Perfectly in tune with the roadster's character, it combines the unpretentious atmosphere of a high-performance sports car with the comfortable, stylish ambience you come to expect in a luxurious touring car.

The wrap-around effect has class

In conjunction with the beltlines on the doors and the parcel shelf, the upper section of the dashboard creates a formal unity and - with the exception of the black interior - it is always styled in a contrasting colour. Generously used wood trim extends from the centre console across the dashboard into the doors, creating a pleasant wrap-around effect. Three types of wood along with two different aluminium trim finishes are available (high-gloss brown walnut, satin-finish light brown poplar, high-gloss black ash), plus two differently treated longitudinal-grain aluminium trim parts (light or dark). The links between the dashboard, centre console and door trim panels have been styled so that they are continuous and they support the wrap-around effect. Minimal gap dimensions please the eye and represent the high precision with which the SL is manufactured.

High-quality instruments add emotionally appealing flourishes

In the area of the dashboard, four circular ventilation outlets provide some striking eye-catching touches. Set in metal, these air vents are reminiscent of jet engines and are a contemporary, emotively interpreted way of paying homage to the history of Mercedes-Benz sports cars.

Inside two tubes the sporty instrument cluster boasts classic round dials with three-dimensional graduated rings, back-lit dials in the centre of the tachograph and rev counter, plus high-quality needles. In the centre between the two round dials, a colour display provides information from the on-board computer and indicates vehicle functions. The system is operated via a three-spoke sports steering wheel with shift paddles and twelve function buttons. The steering wheel featuring a flattened bottom section has an ergonomic grip area and galvanised spokes, and is covered with nappa leather - in the airbag section, too.

A large COMAND colour display in the centre of the vehicle takes care of the numerous display functions for the entertainment, communication and navigation facilities. A particularly eye-catching feature on the tunnel of the centre console is a new DIRECT SELECT shift lever. Small and fine, it is a true visual highlight. Like the central rotary knob for operating the COMAND system, it is optimally positioned from an ergonomic point of view. Located in front of these controls is the lidded compartment for the two cup holders.

Spotlight on the stylish ambience

Making dynamism visible is what it's all about where the ambient lighting in the SL is concerned. The fibre-optic cables with three colour options to choose from stretch between the beltline and the door centre panel in one tier over virtually the entire length of the door, behind the trim on the dashboard and in the front panelling.

Seats with a noble, sporty character

The new Mercedes-Benz SL-Class's fully electric seats with a memory function meet discerning and wide-ranging standards regarding seating comfort, ergonomics, safety and sportiness. The ergonomically optimised seats themselves are more slender than in the predecessor and emphasise the noble, sporty character. This is underlined in visual terms by sophisticated stitched seams and by a layout which varies depending on the choice of leather. Alongside excellent lateral support, the seats also offer high levels of comfort.

The superstructure of the seat cushion and backrest is formed by a weight-optimised welded construction of steel and sheet metal panel parts. This structure also makes a significant contribution towards transverse support for the sidewall in the event of a lateral collision. In addition, a thorax-sidebag is installed in the backrest. A newly developed combination of a sine spring core principle with rubberised matting and a foam layer as damping ensures support and comfort.

Both the driver and the passenger can adjust their seats precisely according to their requirements and body measurements. Even in the standard equipment there are extensive electrical adjustment options available for doing so, enabling fore-and-aft and height adjustment to be made just as easily as the seat cushion angle, cushion depth and backrest angle adjustment. The crash-responsive head restraints are also adjustable for height. The range of equipment also includes 4-way lumbar support adjustment - this feature is housed in the centre section of the backrest cover. The occupants can operate it via the central control panel and the head unit. Using the memory buttons, the current seat position can be stored, and on the driver's side this also applies to the positions of the steering wheel and exterior mirror.

A very attractive solution has been found for convenient access to the rear compartment for easy loading - in both visual and functional terms. A button on the shoulder of the backrest operates the backrest lock electrically and enables the seats to be moved forwards and backwards in order to create sufficient room to manoeuvre.

Also part of the standard specification is a seat occupancy sensor with automatic child seat recognition on the front-passenger side - for child seats with a transponder specially approved for Mercedes-Benz.

For enhancing comfort even further, in the case of the leather appointments the seats are covered with sun-reflecting leather. This specially coated leather reflects the heat of the sun and, in particular where the appointments colours are dark, it reduces the extent to which the surface heats up. In combination with the optional active ventilation the thermal seat comfort is tangibly improved.

The following seat variants can be selected as an optional extra:

• Luxury heated seats with active seat ventilation: it ensures a pleasant seating climate. Leather appointments are a prerequisite for this option
• Active multicontour seat package: three air chambers in the lumbar area can vary the contour of the seats in order to prevent fatigue. Elongated air chambers in both of the side cushions on the backrest ensure optimum lateral support
• Dynamic multicontour seat: the dynamic multicontour seat is an enhanced version of the multicontour seat. It automatically adjusts the lateral structure of the backrest in accordance with the current driving situation. In order to do this it varies the air pressure in the seat bolsters on the backrest electropneumatically, depending on the steering angle, lateral acceleration and speed

Health and comfort-conscious climate

The control panel for the standard-specification luxury automatic climate control THERMOTRONIC featuring separate temperature adjustment for the driver and passenger has been redesigned and revised. Mercedes-Benz has placed particular emphasis on new technologies for saving energy. They include a window demisting sensor integrated in the base of the interior mirror. It measures the window temperature and interior humidity and transmits these data to the climate electronics. They can use them to determine whether the windscreen has misted up. If this is not the case, in A/C operation it can continuously adjust the compressor in the background if no dehumidification is necessary. In other words: thanks to the sensor, the compressor can be operated as required, saving drive energy. The A/C function can remain permanently active. A further advantage is that, as the air conditioning only dehumidifies and cools as much air as necessary, dry eyes are prevented - a tangible gain in terms of comfort.

The air conditioning is also linked to the ECO start/stop function and can therefore also regulate the climate during the stop phases.

So that SL drivers can enjoy an open-air experience even when the weather is cool, the innovative neck-level heating system AIRSCARF is available as an optional extra - as was the case with the predecessor. Warm air flows through a nozzle at the front of the head restraints, and the system directs it around the head and neck area of the occupants.

Room for luggage and lots of equipment

Suitability for everyday use is a key word which is traditionally taken extremely seriously at Mercedes-Benz - even in the case of vehicles designed to be very sporty. This is why the occupants in the new SL will find plenty of stowage facilities for larger and smaller items alike. In addition to the glove compartment, the centre console offers three stowage compartments within easy reach:

• One of these is at the front beneath the air-conditioning control panel, which can be optionally fitted with two cup holders or with an ashtray and one cup holder
• A large stowage compartment beneath the armrest can be used for the safe storage of a telephone, iPod ® or similar, for example
• A centrally located rear box with a retractable luggage cover completes the range. A bottle holder is fitted here as part of the standard specification, whilst a fire extinguisher is available as an optional extra

A lockable rear box behind the driver's seat creates additional stowage space. Its catch is automatically closed when the vehicle is locked.

In the lower section of the door trim, a long, open door pocket offers further, easily accessible stowage space. As no bass loudspeakers have to be fitted in the door thanks to the Frontbass system, Mercedes-Benz makes sensible use of the space gained here by adding an extra stowage compartment, which can be used for an umbrella, for instance.

The designers have also thought the details through: smaller but useful items can be fixed in place by a net on the centre tunnel of the passenger's footwell.

The design of the boot is largely determined by the vario-roof, which has to be housed in the upper part of the boot when the roof is open. In total the new SL offers luggage capacity of up to 504 litres - 364 litres with the roof stowed. There is always room for stowing luggage or two golf bags without any problems at all, thanks to the optimised boot design.

A luggage cover which can be adjusted lengthwise with a handle prevents pieces of luggage from colliding with roof elements in the boot when opening the roof. Only when the cover is adjusted to the rear can the vario-roof be opened. Anyone wanting to use the entire boot capacity when the roof is closed can adjust the cover to the front or remove it completely.

At the press of a button, the roof elements stowed in the boot can be tilted upwards by about 25 degrees to make loading and unloading easier - as was the case in the predecessor (Easy-Pack system).

The compressor and the TIREFIT filler bottle are housed in a stowage compartment in front of the recess which can be accessed by lifting up the boot floor.

HANDS-FREE ACCESS - 'kick' to open

One of the new products and features from Mercedes-Benz is a system known as HANDS-FREE ACCESS, which is included in the KEYLESS-GO package. It is available on request for the new SL for the first time anywhere in the world, and it allows drivers to operate the boot lid without using their hands. This work is taken care of by a hydraulic drive system, for which the control signals are given by the SL owner without touching anything, but by making as though to kick the area of the rear bumper with their foot; doing so activates this fully automatic comfort-increasing equipment. Mercedes-Benz is the only manufacturer to offer a system which not only opens but also closes the boot lid automatically.

With the innovative convenience function HANDS-FREE ACCESS there is no longer any need for drivers to have to get annoyed by having to put their purchases and other objects down on the - often dirty - ground when out shopping and when they literally have their hands full, in order to reach for the handle. Should an unintentional 'kick' result in the boot lid opening or closing without the driver wanting this to happen, a second kick will correct it. When this occurs, the automatic system interrupts the procedure and reverses the effect of the signal given in error by actuating the boot lid against the original direction of movement - in the case of unintended opening, the second kick closes the boot lid again.

An appropriate safety program facilitates unhindered use of the HANDS-FREE ACCESS system. An acoustic signal provides the information that an opening or closing procedure has been initiated, and an automatic reversing function stops the boot lid as soon as the system recognises that there is an obstacle blocking the boot lid.

For the HANDS-FREE ACCESS system to be included, the vehicle must be fitted with KEYLESS-GO - this allows non-contact access to the vehicle In addition to this the correct KEYLESS-GO vehicle key has to be in the vicinity of the vehicle, so in order to open the doors it can, for example, stay in the driver's coat pocket or handbag. In order to activate the HANDS-FREE ACCESS system for the boot lid, the KEYLESS-GO key must not be further than 1.5 metres away from the rear end of the vehicle.

Body and bodyshell: Aluminium comes up trumps

Cars are becoming increasingly safer, more comfortable, but often heavier as well. The new Mercedes-Benz SL not only stops this trend, it turns it around. In spite of increased comfort, performance and safety, it is 140 kilograms lighter than its predecessor.

The greater part of the weight-reduction "diet" is hidden from the eyes of the observer of the SL. Under the aluminium outer skin there is a bodyshell made almost entirely from aluminium, only very few components being made from other materials. The even lighter magnesium is used in part for the cover behind the tank. The A-pillars and the roof frame are of steel sheet metal incorporating high-strength steel tubing. For these elements steel is the best solution to provide survival space for occupants in the event of the vehicle overturning.

The bodyshell of the Mercedes-Benz SL-Class is the first all-aluminium bodyshell to be produced in large series at Mercedes-Benz. This entirely new development weighs 254 kilograms and is thus 110 kilograms lighter than a comparable steel bodyshell. Further extensive lightweight design features compensate the additional weight unavoidably caused by the increased comfort, the new assistance systems and other technical features. Under the bottom line an enormous weight advantage remains for the new SL. As the SL500 it weighs 125 kilograms less than its predecessor, while the SL350 weighs 140 kilograms less than its previous version. And its preceding model already had a lightweight aluminium bonnet and doors.

"The effect is rather as if a heavyweight-class passenger had got out of the car and taken their heavy flight luggage, too" says Dr Thomas Rudlaff, responsible for the aluminium bodyshell at Mercedes-Benz. "The result is perceptible and measurable. Less weight means more dynamism and less consumption. In other words: the motoring enjoyment increases and the environmental burden decreases."

For the roadster the aluminium bodyshell is superior to a steel construction

The developers at Mercedes-Benz did not rest content achieving weight benefits alone. The aluminium structure had to be superior to a steel construction in terms of rigidity and comfort as well. In order to attain this high objective, developers consistently went for an intelligent lightweight construction, and explored many new paths to do this. Every single component of the aluminium bodyshell was specifically optimised for its particular function and expected loads. Thus, diverse processes are used to make different kinds of aluminium depending on the use the component is to be given: the parts are made by chill casting or vacuum die casting, worked into extruded aluminium sections or into aluminium plates of thicknesses that vary within one and the same component; these are what are known as the tailored welded blanks. Expressed in numbers, the bodyshell weight is made up of: 44 percent cast aluminium, 17 percent aluminium sections, 28 percent aluminium sheet metal, 8 percent steel and 3 percent of other materials.

At the Bremen production facilities the parts are assembled using diverse load-adequate joining methods, some of which are innovative processes. Secure joints are ensured, for example, by MIG welding, hemming, bonding, self-piercing rivets, flow hole bolting, or friction stir welding - a joining method by which a highly resistant weld seam is produced by means of friction heat; a method particularly well-suited to aluminium on account of its low melting point.

Particular highlights of the bodyshell:

• The firewall is at present the largest aluminium cast component made in large series for vehicle bodywork
• Many sheet metal parts are designed in such a way that for the first time they can be made from 100-percent recycled aluminium, saving 80 percent of the energy used in their production.
• The main floorpan consists of a 3-layer shaped panel made from thin, extrusion-moulded hollow sections, welded together by friction stir welding.
• The longitudinal members in the vehicle front end are made using high-pressure hydroforming (IHU) technology, which enables the creation of highly complex and robust components, permitting optimum use of reduced installation spaces.
• The door sills (longitudinal members) consist of 1.7 metre-long, 7-chamber extrusion-moulded aluminium sections; these provide rigidity in the lateral sectors and safety in the event of a collision. Flexible chamber distribution makes possible a minimum component weight coupled with optimum characteristics.
• The tunnel is made of aluminium sheet metal with a reinforcement of varying thickness (3 different thicknesses depending on the sector, a so-called tailored welded blank, TWB).
• The rear sector floor is a MIG welded frame with a hollow chilled cast longitudinal member as its central element. This technique is employed in the SL for the very first time in automotive bodyshell construction.
• The rear sector floor frame structure is closed by floor sheet metal panels and the boot tub made by vacuum die-casting.
• The boot recess is made from recycled sheet metal.
• The central member connects the front end with the rear sector floor. The mounting points for the drive shaft, the transmission cross beam, the transmission tunnel braces and the seat bolting points on the tunnel side are all integrated into a single element. The wall thicknesses and rib distribution are oriented bionically towards the requirements and loads.
• Many other components were optimised bionically, i.e. based on examples from the natural environment. These structures reduce the vehicle weight compared to a classic design even further.

The sum total of all the design measures leads to a lightweight, torsionally and flexurally rigid bodyshell with an optimum rigidity/weight ratio. It was possible to increase the bodywork's torsional rigidity by more than 20 percent over the already highly rigid preceding model series. This is confirmed by measurements of the new SL's torsional strength - at 19400 Nm per degree the roadster achieves an absolute top value (its predecessor already reached 16400 Nm per degree).

Meets the highest safety standards

At the same time the high-strength structural elements of the aluminium bodyshell make the new SL even safer than the preceding model in the event of a collision. Extrusion-moulded sections, connecting cast nodes and a double-thickness plate floor form a passenger compartment that is just as lightweight as it is sturdy. Two aluminium sections in each door together with the side sills (very rigid thanks to their internal chamber structure) and crash-resistant seats provide the greatest possible survival space in the event of a side collision.

A front end deformation zone acting on several levels and in which the aluminium front axle subframe is integrated as an additional third longitudinal member, distributes collision forces to a large area, conducting them past the passenger compartment. And in the rear, too, there is sufficient energy-absorbing deformation potential. A structural cage made from chilled cast longitudinal members, transversal sections and a cast magnesium tank separation bulkhead also contribute to this. This is also where the fuel tank is nested in a crash-protected manner above the rear axle. This way all the

statutory safety requirements are met as well as the even stricter ones from Mercedes-Benz.

Best marks for NVH comfort

Thanks to its innovative aluminium bodyshell concept, the new SL is also unique among the roadsters in terms of NVH comfort (noise, vibration, harshness). One contributing factor towards its optimum vibration and road roar characteristics is a very rigid connection between the front section and rear floor, allowing relaxing travel even over long distances, and at the same time offering impressive driving dynamics.

Although aluminium features a higher sound emission and radiation level than steel, the new SL is the quietest vehicle in its class. Mercedes-Benz compensates for the acoustic disadvantages of aluminium by means of a consistent sound insulation concept with targeted adaptation of the sound damping materials to each problem zone, and through the use of innovative sound-insulation materials:

• A special firewall damping with variable mass distribution and a significant heavy layer proportion attenuates engine noise.
• In conjunction with the plate floor, single-piece, foam-backed carpeting with virtually no seams reduces the roll noise of the vehicle in the interior.
• A spray-on lining attenuates the structure-borne sound in the vehicle interior and exterior.
• Textile wheel arch linings, acoustically absorbing shield plates and bodyshell foam elements for critical sectors also contribute towards a smooth ride.
• Damping in the rear wall transversal cross member and boot lateral elements as well as in the forced ventilation openings prevent disruptive tyre and wind noises from making themselves unpleasantly noticeable in the vehicle interior.

A further contribution to the good interior acoustics is the laminated glass windscreen with acoustic film. The transparent, highly resilient film absorbs the vibrations of the windscreen and reduces the perceptible sound level in many frequency ranges.

The precision workmanship on the acoustics goes so far as to ensure that the hydraulic pump for the electrohydraulic vario-roof is encapsulated and decoupled from the bodyshell. In addition to this, a newly developed insert nozzle sees to it that the pressure pulsation in the pump is reduced to a minimum right from the outset. This means that pump noises are only barely audible for the driver and passenger.

The doors and the bonnet, too, are lightweight

The intelligent material mix is completed by the boot lid, of SMC-hybrid design (SMC = sheet moulding compound). It consists of a single-shell synthetic material panel mounted on a steel reinforcement. Both materials have virtually identical thermal expansion coefficients and complement each other very well. The interior steel construction permits maximum rigidity with minimum use of space, while the plastic panelling allows the full integration of the aerials for navigation, digital radio and mobile telephony out of sight in the rear area so that the SL does not need to carry a bothersome aerial stump on its aerodynamically refined body.

The bonnet of the SL is made from aluminium, as was that of its predecessor. It was optimised in terms of form and materials, contributing towards the outstanding pedestrian protection.

The doors, too, are of a lightweight design and made from aluminium. They are fashioned from a combination of sheet metal, extruded sections and cast metal parts, joined by diverse methods: riveting, bonding and hemming. Their aluminium and steel hinges are friction-based and are infinitely adjustable to any desired angle when opened, so that when getting into or out of the car they can remain securely open at any angle permitted by the space available at the side. This is particularly desirable in cramped parking conditions such as in a garage or car park.

Unique item of equipment: MAGIC SKY CONTROL

The proven electrohydraulic vario-roof - which turns the roadster into a closed coupé with a fixed roof in just a few seconds at the push of a button - has been intelligently enhanced, with Mercedes-Benz continuing to play the pioneering role here. For the new SL Mercedes-Benz is for the very first time offering drivers the choice between three variants of the lightweight-construction vario-roof:

• The base version is a roof painted in the vehicle colour
• As an alternative, a transparent variant with a roller blind can be selected
• The third variant from which drivers can choose is the panoramic vario-roof with MAGIC SKY CONTROL. This glass roof switches to light or dark as required at the press of a button. When light it is virtually transparent, offering an open-air experience even in cold weather. In its dark state the roof provides welcome shade and prevents the interior from heating up when the sun's rays are very intense. In other words: a feel-good atmosphere at the touch of a button

The operating principle is based on the physics of a plate condenser: if the glass structure is subjected to an electrical voltage, particles in the structure position themselves so that light is able to pass through the glass. If the voltage remains switched off, however, the particles position themselves randomly. This partially blocks the light, and the glass remains dark. The control unit and converter are integrated into the front section of the roof, and the switch is in the overhead control console.

In addition to the unique panoramic effect and transparency at the touch of a button, MAGIC SKY CONTROL also provides an atmosphere of wellbeing. UV and infrared light are also effectively blocked in transparent mode, while insulation increases even more significantly in the darkened mode, thereby helping to keep the temperature on interior parts such as armrests cooler by up to ten degrees Celsius compared with conventional green glass.

Since the innovative glass also shields against the sun's rays far more effectively than conventional thermal insulation glass or sunblinds, the occupants of the new Mercedes-Benz SL-Class will also enjoy the highest level of climatic comfort at the same time. When driving with the roof open would be unpleasant due to intense heat, the driver and passenger are able to remain composed under the MAGIC SKY CONTROL roof - making an important contribution towards driver-fitness safety, a concept which Mercedes is well known for promoting. Even when the vehicle is at a standstill the interior does not overheat, since the roof is switched to darkened mode when powered off.

But MAGIC SKY CONTROL not only benefits the occupants. Some of the strain is also taken off the air conditioning, thereby saving on CO2 emissions.

The frame of the three roof variants is now made of magnesium. This makes each roof around six kilograms lighter than in the previous model, giving the car a lower centre of gravity, and therefore better agility.

The engineers have refined the operating mechanism for the roof and boot lid. It now takes less than 20 seconds to open or close the roof completely.

Sophisticated corrosion protection concept

The aluminium bodyshell of the new SL offers no point of attack for corrosion. A sophisticated surface protection concept ensures the preservation of the brilliant look both of the outside skin and of the underside of the sheet metal panels, thus simultaneously protecting the renowned reliability and value stability of Mercedes-Benz vehicles. The protection concept was developed and tested on the basis of the environmental burden in different climate zones of the world and the specific loads the vehicle is subjected to.

The foundation for maximum corrosion resistance is formed by corrosion-resistant aluminium alloys and design features, while the few steel vehicle components are all fully galvanised. High-quality zinc/nickel coatings or special electrochemical insulation measures prevent contact corrosion with aluminium. All the seams are meticulously sealed, the surfaces protected through cathodic dip priming and multiple coats of paint. Sectors particularly exposed to corrosion are additionally protected with wax, to ensure that the pristine aspect of the new car is preserved for a long time.

Intelligent Light System and LED tail lights as standard

The headlamps on the new SL have been enhanced. As part of its standard specification, the new roadster is equipped with the Intelligent Light System (ILS) featuring bi-xenon headlamps. A driving direction indicator, sidelights and the daytime running lamps with LED technology complete the Intelligent Light System.

The tail lights on the new SL benefit from the advantages offered by the LED technology. LEDs light up approximately 150 milliseconds faster than conventional bulbs, plus they have a considerably longer life and conserve current. In the SL's tail lights, the LEDs also light up with differing intensity in a targeted manner in certain sections of the tail lights, depending on the light function. This technology ensures an unmistakable night design.

Rear reversing lights and rear fog lamps are integrated into the rear bumper. The third brake light featuring LED technology is integrated in the boot lid above the Mercedes star.

Lightweight construction under the microscope: Progress in detail

Right from the word go the target was ambitious: the aim was for the new Mercedes-Benz SL-Class to tip the scales weighing five percent less than the previous model. Already declared the benchmark, the predecessor itself was a shining example boasting various lightweight design measures, even including bonnets made of aluminium. At the same time, the specifications book prescribed more comfort, more output coupled with considerably reduced consumption and fewer emissions, plus a more rigid bodyshell and even more safety. These demands would render the vehicle heavier and not lighter - that was clear. The experts calculated a weight increase of at least 75 kilograms.

Only a lightweight construction on a totally new level - which included all the vehicle components in the equation - could reconcile these contradictory requirements. In actual fact, the developers at Mercedes-Benz have succeeded in undercutting the ambitious weight targets. The new SL500 weighs no less than 125 kilograms less than the predecessor of the same name. This corresponds to a reduction of 6.5 percent. Meanwhile the SL350 even manages to exceed the high expectations even further - with its weight saving of 140 kilograms - equating to 7.7-percent less.

Bodyshell. Converting the entire bodyshell to aluminium cuts its weight by 24 percent in contrast with a steel bodyshell featuring comparable properties (a weight saving of 110 kg). Even the upper door hinges consist of aluminium.

Damping. The switch from absorber foams to sprayable acoustic compositions with variable layer thicknesses which can be shaped according to requirements, plus modified underbody panelling, results in weight savings in the order of 2.5 kg.

The guide rails for the window lift mechanisms are now comprised of aluminium instead of steel, amounting to a weight saving of 0.5 kg.

Vario-roof in magnesium/plastic design.The front part of the roof and the C-pillar are produced in magnesium/plastic, plus there are additional optimisation measures regarding the design of the tubular frame, rear shelf, rear window frame and roof frame. The weight reduction amounts to 15 kg.

Glazing. The windscreen is 0.5 millimetres thinner, with an acoustic film. The weight reduction amounts to over 1 kg.

The rear windscreen is 0.7 millimetres thinner, resulting in approximately 1 kg less weight.

Interior. The dashboard mount consists of a continuous IHP aluminium tube with magnesium struts and moulded-on polymer brackets. The weight reduction is 2.2 kg.

With the introduction of shift-by-wire technology, the large shift lever has been replaced by a joystick-like lever. This DIRECT SELECT gearshift system weighs only one sixth as much as the automatic selector lever used in the preceding model. The weight saving is 1.4 kg.

The boot floor is in the form of a polyurethane honeycomb plate instead of the wood plate previously used. The passenger's foot plate has been switched over to plastic from steel, saving 1.5 kg in weight.

Seat. New seat structure with new adjustment motors, but a standard-fit 4-way lumbar support and crash-responsive head restraint. Weight savings: 11 kg.

Electrics. Thanks to an intelligent dynamic load management system, two batteries are no longer necessary; one 95 Ah battery in the boot is sufficient, supported by a 12 Ah battery for the ECO start/stop function. Weight savings: approx. 4 kg.

Every vehicle is given a customer-specific wiring harness for the interior, cockpit and engine compartment. Thanks to this tailor-made cable harness, additional weight in the form of wires which are surplus to requirements can be saved - to the tune of up to 0.4 kg.

The innovative Frontbass system avoids the need for a separate woofer and door loudspeaker. Weight reduction: over 4 kg.

Axles. The four-link front axle had already undergone extensive weight optimisation for the preceding model, featuring steering knuckles and spring links made of aluminium. The two front-axle halves now consist entirely of this material. The integral support frame for the front-axle halves, steering gear and engine is also produced in aluminium. Total weight savings: 11 kg.

The rear-axle subframe consists of high-strength steel with adapted panel thicknesses. It has been optimised in accordance with the specific engine line-up for the SL350, resulting in a weight reduction of 2.6 kg over the SL500.

Suspension, Damping. The standard-specification semi-active adjustable damping in the SL350 is lighter than the standard suspension system, saving 10 kg in weight.

Brakes and pedals. Optimised brake cooling eliminates the need for large and thus heavy brake discs on the front axle. Weight savings: 3.8 kg.

Lightweight wheels. New standard-fit lightweight wheels for the SL500 are around 15 percent lighter than cast wheels. Weight saving: approx. 4 kg

Wheel bolts with a weight-optimised head. Weight saving: approx. ¼ kg.

MAGIC VISION CONTROL adaptive windscreen washing system: Visibility as if by magic

An astonishing experience: the wiper blade glides over the badly soiled windscreen of the new SL, without a sign of a cleaning water jet, the occupants do not notice anything yet the windscreen is still cleaned! The new SL is the first vehicle to be equipped with the adaptive MAGIC VISION CONTROL wiper/washer system developed by Mercedes-Benz. It cleans the windscreen without the splash of water that usually briefly disrupts the driver's field of view in the case of conventional windscreen washing systems - something that is especially unpleasant at night or when the sun is low in the sky and at high speeds.

In fact, the windscreen cleaning operation in the Mercedes-Benz SL-Class is still performed with washer fluid in the conventional manner. The innovation lies in the way the fluid is conducted to the windscreen in order to clean it. This is done by means of water guides integrated on both sides along the wiper blade - one on the left and one on the right - with minute laser-cut spraying holes. Via these channels, the innovative washer/wiper system always supplies washing fluid to the windscreen discreetly, precisely where it is needed: just in front of the wiper blade lip, according to the direction of movement of the wiper. The holes are distributed along the entire length of the wiper blade, being more closely spaced towards the outside of the blade, where it sweeps a greater area, than closer in, where the area swept is smaller.

Programs for summer, winter and cabriolet operation

Mercedes-Benz controls the MAGIC VISION CONTROL system intelligently via three partly autonomous wash programs - for summer, for winter and for cabriolet driving. It is the first windscreen wipe/wash system anywhere in the world to operate in this way. In summer, small quantities of water are sufficient to remove a light powdering of dust. In winter the dirt mixed with de-icing salt requires a greater amount of water. The MAGIC VISION CONTROL system works in accordance with the outside temperature, and it also automatically adapts the washer fluid quantity to the surrounding conditions.

A particularly interesting feature of the SL Roadster is the Cabriolet function: when the hardtop is down, the electronic control system reduces the amount of water, apart from which it demands the required water mainly on the downward stroke of the wiper arm. This way the windscreen can be conveniently cleaned during the journey and with an open roof, without any of the water spraying into the vehicle interior. Another pleasant side effect is that, since the washer fluid is directed specifically and in a well-metered manner to the area to be cleaned, one doesn't douse anyone else in the surroundings with water, either, and it also doesn't distribute any spray onto the vehicles behind. At the end of the day, a better cleaning effect is attained with up to half the amount of washer fluid. It has therefore been possible to reduce the volume of the washer fluid reservoir by 1.7 litres compared with the preceding model. This in turn contributes to a reduction in weight and consequently to greater efficiency.

Winter-proof thanks to the heated system

On request the MAGIC VISION CONTROL wiper blades are completely heated on the new SL, making Mercedes-Benz the first manufacturer in the world to offer a fully heated wiper/washer system. It consists of a washer fluid container heated through coolant waste heat, electric heating for the entire hose system and, as a newly-developed highlight, a fully heated wiper blade. This effectively prevents the formation of snow on the wiper blades, so typical in winter. To do this each of the spring rails of the blade is equipped with a heater foil with an output of 35 watts per blade. It heats the spoiler and the wipe lip. Snow and ice cannot freeze onto the blade; it remains supple in winter, too, and always cleans well.

The heating is also controlled as required according to the duration of operation and the outside temperature. It is only below a temperature of minus 20 degrees Celsius that the system makes use of the entire system's maximum output, 270 watts. Between 5 degrees above and 20 degrees below zero the heating operates in an energy-saving mode and only requires the output needed to thaw out the wiper/washer system and keep it free of snow and ice.

Aerodynamics: Breezy, but never bothersome

Open-top motoring should be nothing but sheer pleasure: smelling the forests and meadows, hearing the birds singing, savouring the sound of the sea, feeling the warmth of the sun. And in spite of this proximity to the natural world, the occupants in the new SL do not have to relinquish comfort. Even at higher speeds they are largely unaffected by any strong winds. In this respect, just like its predecessor, the new luxury roadster is unsurpassed by no other open-top two-seater.

First and foremost it is the rigid aluminium bodyshell and - one of the brand's hallmarks - sophisticated aerodynamics which ensure excellent comfort during open-top motoring. The designers' intelligent and highly efficient work has resulted in superb aerodynamic properties for the SL in several respects. This means that the roadster earns top marks in no less than four important disciplines within its segment:

• Best cd figure
• Wind noise on a par with a saloon
• Open-top motoring in maximum comfort
• Best anti-soiling measures

Top-class: cd figure

The new SL shines with a cd figure of 0.27 (in the SL350). Never before has a vehicle in the roadster segment achieved such a low cd. At the same time, the cLR value (the coefficient of lift at the rear axle), which is decisive when it comes to braking stability, is reduced by 0.01. This ensures a lower lift at the rear axle than at the front axle - which is important for comfortable, safe handling at high speeds and/or when there is a crosswind.

The fact that not only could the cd figure be cut to a record low but that it was also possible to reduce the wind resistance as a whole is even more astounding when taking into account the fact that the new SL's frontal area is around four percent larger than that of its predecessor - due in part to its wider track. The product of the frontal area and the cd figure is, however, smaller.

Alongside a great deal of precision work, some of the other factors which contribute towards the low cd figure are:

• a complete engine compartment and underbody panelling concept,
• a spoiler lip on the top face of the boot lid,
• a specifically designed spoiler lip on the tail light,
• wheel spoilers in front of the front and rear wheels, and
• redesigned exterior mirrors positioned on the beltline and with a mirror base specially optimised for the new SL.

A newly developed aero wheel which is part of the standard specification for the SL350 also significantly reduces the wind resistance. Its rim section is largely closed, which means that the air flowing through the wheel to the exterior disturbs the air flowing past at the outside of the wheel than is the case with a conventional wheel. Together with tyres which have been specially tuned to this end, the aero wheel cuts the frontal area - which is also a decisive factor in determining the wind resistance - by 0.01 square metres. This pays off in the form of a reduction in consumption, which results in one gram per kilometre fewer carbon dioxide emissions.

In order to minimise wind resistance even further, the six-cylinder version of the new SL also employs an adjustable radiator shutter. This consists of a large number of louvres and is positioned between the radiator and the radiator fan. An actuator fixed to the engine's cooling module can be turned to close or open the flow path of the cooling air. In this way the flow of air through the radiator and through the engine compartment can be regulated as necessary. This means that if the engine has low-level cooling requirements, the wind resistance falls, as do the fuel consumption and emissions.

Top-class: wind noise on a par with that in a saloon

Where wind noise is concerned, the predecessor of the new SL was already the benchmark in its segment. But its successor surpasses this high level. It is even possible to hold a conversation, listen to the radio and make a telephone call at high speeds. This is thanks in part to the new stand for the exterior mirror. Its shape facilitates optimum flow; both when the inflow is straight and in the case of crosswinds it causes only low wind noise.

The windscreen fitted with multi-layer foil also contributes towards the exemplarily low interior noise, combining a low component weight with good acoustic properties. Low-frequency sounds which can arise through vibrations in the vehicle's bodyshell can to a large extent be prevented by the new SL's aluminium bodyshell, through design measures which were taken into account and tested at an early stage.

Top-class: maintaining a draught-free interior

Even at speeds of around 200 km/h the new SL offers extraordinarily high comfort during open-top motoring, setting new standards here. When the vario-roof is closed and the side windows are lowered, a welcome breeze can be felt during hot weather. Even putting the side windows up tangibly reduces it. The occupants in the new SL enjoy a comfortable and virtually draught-free ride as soon as they use a draught-stop. A conventional, manually operated folding-frame draught-stop comes as part of the standard specification. Covered with a finely meshed, synthetic textile fabric, this draught-stop is mounted behind the seats and folded up by hand. It covers the entire area behind the seat backrests as far as the upper edge of the head restraints. It can be taken off and stowed in the boot as necessary.

A highlight comes in the form of a new electrically operated draught-stop which is available as an optional extra. This new development can also be extended and retracted by the driver or passenger during the journey, via a switch in the centre console. If the switch is operated, a trapezoidal frame is unfolded electrically, and when it reaches its final position a finely meshed textile fabric covers it, thus keeping the area behind the occupants virtually free of draughts. Once it has been retracted, the frame disappears completely in the rear compartment trim cover.

The innovative neck-level heating system AIRSCARF is also available as an optional extra. It emits preheated air from an orifice in the head restraint, and this warm air then wraps itself around the neck area of the occupants like an invisible scarf, therefore even making it possible to have the roof open when the temperature is cool, without any serious inconvenience.

Top-class: anti-soiling measures

Clean exterior mirrors and side windows are important factors where safety is concerned, yet all too often drivers cannot take them for granted. In this respect, the new SL profits from the detailed work carried out by the aerodynamics engineers and can to a large extent ensure clear vision for drivers - even when it is raining. This is achieved mainly through a precisely tuned package of anti-soiling measures. The A-pillar trim with a new shape features an aerodynamically and aeroacoustically tuned front edge and a water guide channel on the top edge prevent water from flowing from the windscreen to the side windows. The new exterior mirror has also been optimised for journeys during rainy weather. Water guide runnels and additional drip edges have been integrated into its housing, and to a large extent they keep water away from the mirror glass, and shift the break-away point of the droplets to the outside. As a consequence of the aerodynamic measures the side windows soil only slightly.

Engine and drive system: The power and the economy

Rich power reserves plus modest fuel consumption - this formula describes the fundamental characteristics of the new SL models. They owe this in part to the two V6 and V8 units from the new generation of BlueDIRECT engines from Mercedes-Benz. As is already the case with the S-Class and the CLS, they now also enable the SL to achieve previously unattained marks for efficiency in its segment. The V8 in the new SL500 has at its disposal 4663 cubic centimetres of displacement from which it achieves 320 kW (435 hp) - so in spite of having around 0.8 litres less displacement that's some 12 percent more than its predecessor (285 kW/388 hp). The consumption, meanwhile, falls by up to 22 percent, with the torque increasing at the same time from 530 Nm to 700 Nm - an increase of 32 percent. The V6 engine for the SL350 has the same displacement as its predecessor - 3499 cubic centimetres - from which it now achieves 225 kW (306 hp). Whilst this means that its output is 7 kW less than the engine in its predecessor (232 kW/315 hp), as the torque simultaneously climbs from 360 Nm to the current figure of 370 Nm, there is no perceptible loss of power - on the contrary, in fact: when accelerating, the new SL350 even proves superior. Plus the new V6 impresses with its outstanding consumption figures. It is content with 6.8 litres over 100 kilometres, making it almost 30 percent more economical than its predecessor (9.7 l/100 km).

Thanks to the economy of both engines, it has been possible to decrease the volume of the fuel tank from 80 litres to 65 litres. Nevertheless a greater range is available than was the case with the predecessor.

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