- About 50 per cent of all panels made of ultra-high-strength high-tech steels
- PRE-SAFE® as standard equipment with additional preventive safety functions
- Pressure sensors for rapid activation of the side and window airbags
- Sophisticated safety features at the front end to protect pedestrians
- Aerodynamics and aero-acoustics improved even more
- High-intensity projection-beam headlights and flashing stop lights
Safety, comfort, dynamics and longevity - these and other outstanding features of the new S-Class are based to an important degree on its body shell. It acts as a sturdy backbone that reinforces the chassis, ensures precise handling and prevents uncomfortable vibrations. It also fulfils the most stringent Mercedes safety guidelines and features an intelligent lightweight design, exemplary aerodynamics and noticeable improvements in the area of acoustics. The high design quality of the new flagship Mercedes model likewise owes a great deal to the body technology - with its carefully formed panels, precise joins and exact surfaces.
In other words, the body shell of the new S-Class is a perfect example of the successful integration of a great variety of approaches, aims and requirements. Ultramodern development methods - from crash simulation to digital production planning - helped the Sindelfingen engineers reconcile conflicting objectives and achieve new first-class results. For instance, the static torsional rigidity of the body shell - an indicator of safe and comfortable handling - was improved by about twelve per cent relative to the previous S-Class. The flexural strength is about six per cent higher than that of the predecessor model.
These figures are the result of a careful selection of materials according to the proven Mercedes principle “ the right material in the right place.” Steel, aluminium and plastic are the components of the material mix, with steel continuing to play the main role. But here too, the technology is changing: Conventional deep-drawing steels are becoming less important, and in the new Mercedes-Benz S-Class they make up only about 30 per cent of the total. Instead, the experts in Sindelfingen are preferring high or ultrahigh-strength steel alloys, because they achieve a maximum of rigidity with a minimum of weight. Whereas these steels accounted for only six per cent of those used in the predecessor model, for example, they make up about 43 per cent of the total in the new S-Class.
In addition, ultra-high-strength alloys are used for the areas of the body important for passenger protection. These steels are shaped when they are still hot and therefore achieve an extremely high tensile strength of up to 1,500 megapascals, which is three times stronger than conventional steels. The side members and B-pillars are made of these ultra-high-strength steels.
In all, high-tech steel alloys make up about 50 per cent of the body in the new S-Class - a peak value in passenger car technology.
Mercedes-Benz uses the lightweight material aluminium in the places where it provides the most benefits relative to steel. In the new S Class, these areas are as follows:
- front wings
- boot lid
- front module carrier
- rear module carrier
- rear wall behind the rear backrest
- rear centre piece
The contribution of aluminium to the lightweight design of the new S-Class can be seen in the example of the bonnet. It is about eight kilograms lighter than a similar component made of steel.
The spare wheel well is likewise made of a lightweight material: improved glass mat thermoplastic (GMT).
Greater use of plastic recyclates and natural materials
High-quality recyclates and renewable raw materials also play an important role in the new S-Class. To close the material cycle and impart some momentum to the process of recycling high-quality automotive plastics, 45 plastic components with a total weight of about 21 kilograms have been approved for use as recyclates. In terms of weight, there has thus been a four per cent increase in the amount of recyclate components relative to the predecessor model. Recyclable components can be found in all parts of the body - from the underfloor panelling to the wire troughs, from the washer fluid container to the strut moulding.
Mercedes-Benz backs up its pioneering role in the use of renewable raw materials in automotive design by utilizing cotton, wool, natural latex, fibres of wood, flax and coconut, and olive pits. Natural materials of this sort are used to make 27 components that weigh roughly 43 kilograms in all, an increase of about 73 per cent compared to the predecessor model.
By making greater use of renewable raw materials, Mercedes-Benz is conserving resources and contributing to a reduction of carbon dioxide emissions. And compared with conventional materials, natural fibres also offer other advantages, such as lower component weight, better fracture behaviour in collisions, good recycling properties and high comfort.
The S-Class is the world’s first car with an environmental protection certification. The certification attests to the environmentally oriented development process of the saloon, which satisfies the requirements of the international ISO standard 14062. Verification of this is provided by the certification office of TÜV Management Service GmbH.
Adhesive bonds for maximum load-bearing capacity
In addition to the high-tech materials, the combination of modern bonding technologies also contributes to the exemplary torsional and flexural strength of the body. A new high-strength structural adhesive supplements conventional methods like spot and laser welding and low-stress clinching. The adhesive produces a flat bond between the sheet metal flanges, significantly increasing load-bearing capacity and power transmission in areas with a safety function. The total length of the high-strength adhesive seams in the body shell of the new S-Class is 180 metres, more than twice that of the predecessor model.
The precise design of the body components, the low-stress joining technology and the modern spot and laser welding methods largely eliminate the need for additional soldered joints and the MAG (“metal active gas”) weld seams at the junction points of the panels - an important contribution to the durability of the body.
Repair-friendly body modules at the front and rear sections
For the new S-Class, the Sindelfingen engineers again adopted the proven module design for the rear and front sections, but they improved on this design in some matters of detail. The bumper cross members of the modules now consist of high-strength aluminium extrusion profiles. They are connected to the side members via steel crashboxes and designed in such a way that the energy of impact is first absorbed by the aluminium sections and the crash boxes at low collision speeds. The portions of the body shell behind them thus remain undamaged. In addition, the sturdy cross members take on the job of transferring energy to the non-stressed side of the body structure during an offset frontal impact.
The front and rear modules are bolted to the body and can be replaced without elaborate and costly welding work during accident repairs. The individual components within the modules are likewise connected to one another by bolts.
Distribution of impact forces to several planes
The front module and the frame-type integral support, to which the engine, front axle and steering are attached, connect the front side members with the second side member plane above the wheel housings. During a frontal collision, this gives rise to two important paths along which forces and loads are transmitted, which is one of the major reasons for the exemplary passenger protection of the S-Class. Similarly, the solid, multi-layer side skirts can absorb large forces and divert the impact energy past the occupant cell. In serious offset collisions, the front wheel receives support from a specially designed wheel impact element that forms a forward extension of the side skirt.
Likewise new in the S-Class is the concept of the continuous bulkhead cross member. In a frontal collision on one side, it distributes the impact forces over a large area, into the centre tunnel and the side members at the sides. An additional upper member increases the stiffness of the bulkhead and reduces the extent to which the pedals are pushed into the passenger compartment during a front-end impact.
The new V engines of the S-Class make an important contribution to passenger safety as well. Because of their compact design, they allow greater deformation in the frame front-end structure during a front-end impact, reducing the strains on the passengers. For the first time, the cardan shaft has likewise been equipped with special deformation elements.
The distribution of the impact forces onto several vertical and horizontal planes specifically designed to carry certain amounts of load not only helps keep passengers safe; it also makes collisions with smaller vehicles less “uneven”. The front-end structure of the new S Class is designed in such a way that it purposefully dissipates collision energy for the other vehicle, too.
Sturdy underbody structure with eight side member sections
The occupant cell proves to be almost completely resistant to deformation in front, rear or side collisions or when overturning. Passengers can thus be assured of an intact space even when the speed of collision is high. High-strength steels and panels with greater material strength play an important role here, as does the installation of additional support members.
A complex and carefully designed underbody structure forms the sturdy foundation of the passenger safety provided in the new vehicle. Eight side member sections, four cross members and a three-part tunnel reinforcement stabilize the passenger compartment in a crash and ensure that impact forces are distributed over a large area. By way of comparison, the predecessor model of the new S-Class was equipped with two continuous side members in the underbody area.
Instead of being flat, the sheet metal panels between this multiple-piece supporting structure have a new, asymmetric, arched structure. This structure was precisely calculated and lends the panels a great deal of rigidity, about five times as much as in the predecessor model. Greater rigidity simultaneously means less vibration: The arched structure reduces vibrations to a minimum and thus makes an audible contribution to the exemplary driving comfort of the new S-Class.
Mercedes has a patent on the asymmetrically arched floor pan, which was developed by the Sindelfingen engineers together with their colleagues from Daimler-Chrysler research. It is based on insights from the field of bionics.
Side structure made of ultra-high-strength steel for the first time
In a side crash, the main elements that come into play to stabilize the occupant cell are the sturdy side skirts, the B-pillars, the four cross members in the underbody section and a solid steel section below the dashboard. For the first time, Mercedes-Benz is producing the sills and B-pillars with ultra-high-strength steel alloys, which are far superior to all other materials in terms of their tensile strength. By connecting the B-pillars to the structure of the roof frame over a large area, the Mercedes engineers can not only avoid using a transverse piece in the middle of the roof but also reduce the cross section of the A-pillars and thereby improve visibility for the driver.
The doors are made of an aluminium-steel combination with interior frames of aluminium die castings and extrusion profiles to reinforce the window frames. The protection from lateral impacts is improved by high-tensile steel reinforcing sections on the inside. The Mercedes engineers paid extra attention to the door hinges as well and developed special high-strength fastening surfaces. This results in a sturdy coupling in the side structure that provides effective protection to passengers during a lateral collision.
In addition to a high level of safety, the doors of the new S-Class have functions which make access and egress more convenient. A newly developed hydraulic system ensures that from an opening angle of 15 degrees the doors are arrested in any position — even on gradients or in strong winds. When needed, an electric servo-locking mechanism closes all the doors (and the boot lid).
Rear structure for extreme impact stresses
As with front and side impacts, the new S-Class satisfies the most stringent safety requirements for rear crashes too, such as the new U.S. laws specifying an offset crash (70 per cent) with an impact speed of 80 km/h.
The occupant cell remains largely undamaged despite this extremely heavy strain, thanks to the meticulously designed deformation zone in the rear. In addition to the aluminium transverse section and the steel crash boxes of the bolted rear module, it consists of two sturdy side members and a cross member in the area of the boot floor. The suspension sub-frame of the rear axle likewise forms an energy-absorbing plane in the event of an impact. The fuel tank is located in the protected area in front of the rear axle.
Still greater commitment to pedestrian safety
Another focus of development for the safety systems of the new S-Class was the issue of pedestrian protection. It is not new for Mercedes-Benz. The engineers of the Stuttgart-based automotive brand have long been making efforts to reduce the risk of injury to the “weakest” road users - pedestrians and those on two-wheeled vehicles. Bodies with flat surfaces, energy-absorbing bumpers, laminated glass windshields, collapsible exterior mirrors, rounded door handles and “recessed” windshield wipers are only a few of the details of the Mercedes passenger cars that serve this purpose. Mercedes’ active safety innovations such as the BAS Brake Assist also make an important contribution to passenger safety, because they can prevent accidents involving pedestrians from happening in the first place or else significantly reduce the speed of impact. Studies conducted by the Sindelfingen engineers confirm this.
With the new S-Class, the long-standing Mercedes commitment to pedestrian safety reaches a new high point:
- The bottom side of the bonnet was designed in such a way that it deforms to absorb the impact energy in the event of an accident involving a pedestrian. A newly developed, flexible hinge supports the deformation of the engine bonnet to reduce the risk of injury to pedestrians and cyclists during an accident.
- The front wings are connected to the upper side members by a special fastening element. It has a precisely calculated rigidity and bends according to design during an impact.
- The deformation space between the engine bonnet and the assemblies below it was enlarged in two ways: Firstly, through the new external contour of the saloon, which is about 22 millimetres higher in the front section than in the predecessor model. Secondly, the engine, shock absorber towers, reservoirs and control equipment were placed up to 13 millimetres lower.
- The Mercedes engineers have also reduced the overall height of the wind-shield wiper system in order to enlarge the deformation space.
- The front bumper of the new S-Class features a flush-fitting spoiler lip with a foam filling, so the pedestrian is evenly cushioned right away.
PRE-SAFE®: second generation with inflatable seat cushions
The predecessor model of the S-Class ushered in a new era of passenger car safety with the preventive passenger-safety system PRE-SAFE® and intelligent restraint systems that adapt to the current passenger and accident situation. Mercedes-Benz has now refined this pioneering concept still further: through a newly developed crash sensor system for early identification of the type and seriousness of an accident, and through additional PRE-SAFE® functions.
Since its world premiere in 2002, the preventive passenger-safety system PRE-SAFE® has proven itself in over 140,000 S Class saloons. It is fitted as standard equipment once more in the new top-of-the-line model from Mercedes. PRE-SAFE® recognizes a potential accident situation in its early stages, and prepares the vehicle and its occupants for the expected impact. If, for example, the vehicle is in danger of skidding, or the driver is forced to brake hard, PRE-SAFE® will tighten the front seatbelts as a precautionary measure and also adjust the passenger seat into the most favourable position. If necessary, it will even close the vehicle’s sunroof. The system also adjusts the electronically controlled indi-vidual seats in the rear of the vehicle.
Such precautionary measures ensure that seatbelts and airbags offer the best possible protection in the event of an impact. If the accident is averted, PRE-SAFE® releases the seatbelt tensioners again and the passengers can return their seats and the sunroof to their original positions. The system is then ready to go into action again if necessary.
The PRE-SAFE® early recognition system for accidents is based on a unique combination of active and passive safety elements. PRE-SAFE® is networked with standard-equipment safety systems such as Brake Assist (BAS) and the Electronic Stability Program (ESP®), whose sensors are able to recognize potentially dangerous driving manoeuvres. This data is transferred to an electronic control unit that activates the preventive passenger protection when certain thresholds are exceeded.
For the second generation of this unique safety system, the Mercedes engineers have further refined the interaction between active and passive safety features. This means, for instance, that the radar-based PLUS brake assistant linked up with PRE-SAFE® makes it possible to recognize potential dangerous situations before they actually occur and implement precautionary protection measures for vehicle occupants more quickly than was previously the case. The S-Class thus once more opens up new dimensions of passenger car safety. No other car offers such a comprehensive safety system that goes into action even before an accident occurs.
Whereas in the past PRE-SAFE® operated in response to emergency or panic braking - in reaction to a reflexive step on the brake pedal - the system in the new S-Class can be triggered when the PLUS brake assistant has calculated an impending rear-end collision using the radar system and a certain deceleration threshold is exceeded during the braking process. The system will then tighten the front seatbelts and adjust the front and rear passenger seats as precautionary measures, thereby preparing occupants for a possible impact in such a way that seatbelts and airbags can provide the best possible protection.
Mercedes-Benz is supplementing the aforementioned proven PRE-SAFE® features in the new S-Class with additional precautionary features. These will prepare occupants for potential accidents even more extensively — always with the overall objective of ensuring that seatbelts, seatbelt tensioners, belt force limiters and airbags will all work perfectly in the event of a crash.
- A newly developed multi-contour seat makes it possible to more effectively fix the position of the driver, front passenger and rear occupants, and thus significantly restrict dangerous movements of the upper body in a crash. When the PRE-SAFE® control unit recognizes a dangerous driving situation, it will activate within seconds air cushions in the seats (front) and backrests (front and rear), which envelop and support vehicle occupants. Crash tests conducted at the Mercedes-Benz Technology Centre show that this new PRE-SAFE® feature and the precautionary tightening of seatbelts increase the distance between the occupants’ shoulders and the door trim by up to 40 millimetres at a lateral acceleration of 0.6 g. This enables the sidebag to provide even more protection.
- Mercedes engineers have also once again improved the brand’s standard windowbags by incorporating an additional precautionary feature: If the new S-Class is in danger of skidding and an accident thus appears likely, PRE-SAFE® automatically closes the side windows, which hold up the windowbags that inflate in the event of a side impact or rollover. This new PRE-SAFE® feature also reduces the risk of occupants being thrown from the vehicle or objects flying into the car from outside.
Safety tailored to body size
If the accident is unavoidable, a powerful restraint system goes into action to protect the occupants in a way appropriate to the need and the situation. Using various sensors, a computer evaluates not only the seriousness of the accident but, for the first time, data regarding what sort of front-seat passenger is involved as well. If the sensor in the seat cushion has identified a small passenger, it deploys - depending on the type of accident - only the first airbag stage initially so that the air cushion is less inflated. If, on the other hand, it senses a larger passenger, both airbag stages are deployed.
In addition, the new S-Class comes with the proven automatic child-seat identification feature that deactivates the front passenger seat airbag when a Reboard child seat with transponder has been recognized. If the front passenger seat remains unoccupied, the airbag, sidebag and seat-belt tensioner on the passenger side are deactivated.
With this enhanced technology, Mercedes-Benz is starting a new trend in safety engineering. Through a restraint system attuned to individual parameters of the passengers, in the event of an accident all the passengers can be protected even better than previously.
Up-front sensors and pressure detectors for precise accident identification
The Sindelfingen engineers have further perfected the crash sensors as well. The new S-Class has a total of eleven installed sensors that provide immediate data on the type and seriousness of a collision:
- Front-end impact: In addition to the central sensor in the airbag control unit, the S-Class is equipped with “up-front” sensors. Because of their exposed position in the front module, they detect the strength of an impact even earlier and with even more precision, so that the time between the crash and the activation of airbags and seat-belt tensioners can be reduced even further. The seat belts can thus be tightened very early so that the passengers are connected to the occupant cell during an impact and also undergo the decelerations of the body structure.
- Side impact: New pressure sensors notify the control unit rapidly and precisely when there is a side collision in the door area. The sensors react when the air between the outer and the interior panelling of the doors is compressed during an impact. Additional side sensors are installed in the B-pillars of the new S-Class.
- Rear impact: The central crash sensor in the interior of the new S-Class detects a rear collision and supplies the information needed to activate the NECK-PRO headrests. When the accident is relatively major, the buckle retractors are triggered in the front and back to fix the passengers in place in the seats.
- Rollover: In side rollovers, a rollover sensor integrated into the airbag control unit can activate the seat-belt tensioners and windowbags.
Seat-belt force limiters for front and rear passengers
In addition to the two-stage frontal airbags for the driver and the front-seat passenger, the standard occupant safety system of the new S-Class also includes six lateral air cushions: two sidebags in the front-seat backrests, two sidebags in the rear side panelling and two large windowbags.
All the passengers have three-point automatic seat belts. The driver and front passenger seats and the outer seats in the rear are also equipped with seat-belt tensioners and belt force limiters. The force limiter of the front belt straps is adaptive: After attaining a certain maximum level of force, the force limiters switch to a lower level of force – the belts are loosened so that front passengers can plunge deeper into the airbags. This reduces the impact on the chests of the occupants.
The newly developed steering column serves the same purpose. During a front-end impact, it collapses like a telescope by up to 80 millimetres.
Crash-responsive headrests with additional comfort features
The crash-responsive NECK-PRO headrests are another special feature of the safety system of the new S-Class. They reduce the risk of whiplash injuries in a rear collision. Once the sensors have determined that such a collision has occurred and that the impact has exceeded a defined level, the pre-stressed springs in the headrest are released. As a result, the headrest is shifted some 40 millimetres forward and 30 millimetres upward within a split second. In this way, the heads of the front-seat passengers receive support at an early stage.
After NECK-PRO has been activated, the headrests can be pushed back to their original position by hand, using the supplied tool, after which they are once more immediately ready for use. Mercedes-Benz is offering the NECK-PRO feature for driver and front passenger as an option in conjunction with extra-comfortable headrests.
The extensive passenger-restraint system of the new S-Class at a glance:
Three-point seat belts with automatic belt height adjustment Seat-belt tensioners Belt force limiters PRE-SAFE® Headrest height and angle adjustable Front airbags
Windowbags Automatic child seat detection Front passenger detection with weight classification
In front passenger seat
o = As standard equipment
Mercedes safety after the accident too
The comprehensive Mercedes safety system PRO-SAFE also takes into account the phase after the traffic accident. To prevent follow-on damage, the fuel supply of the engine is automatically blocked in the new S-Class in accidents above a certain severity. The hazard warning signal also switches on to warn drivers approaching from behind and to prevent new accidents.
After an accident in which airbags are deployed, all the side windows open just enough to leave a narrow space through which the interior can be ventilated. At the same time, the door locks are automatically released so that injured passengers can be rescued more quickly. Specially designed crash joints prevent the front and rear doors from becoming deeply wedged during an impact. The passengers can also open the doors after an accident, because Mercedes-Benz uses cables that remain intact after deformation for the internal activation of the door locks. The new S-Class is the first Mercedes passenger car to have markings on the front and rear windows showing the emergency services places where they can cut through the A- and C-pillars in the event of a serious accident to quickly reach injured passengers and provide them with medical care.
Long-term protection: fully galvanized body and paint with nanoparticles
Mercedes-Benz has developed an effective package of features to provide the body with long-term protection against corrosion. It is based on fully galvanized body panels which, depending on their area of use - at the doors, for instance, and at the side rails in the front, side and rear areas - also have a double-sided organic coating. This coating also contains rust-resistant zinc pigments. In addition, regions of the body structure that are subject to severe strains are protected with cavity sealing - the front side members, the upper side rail plane of the front-end structure, the side skirts and the rear wheel housings, for example.
The Mercedes-Benz experts also prevent corrosion by sealing the weld seams. The seam sealing comprises not only the bonnet, doors, boot lid, rear wheel housings and fuel-tank flap but also a great many of the welded joints on the underbody structure of the new S-Class. Thanks to the broad sections of plastic laminate used for the underbody panelling, the Mercedes engineers were able to do without the conventional PVC underbody protection. The underbody panelling protects the body from small stones, moisture and dirt.
Like all Mercedes passenger cars, the new S-Class is protected by a 30-year MobiloLife warranty. Similarly, with the more scratch-resistant clear coat based on nanotechnology, Mercedes-Benz makes another contribution to top quality and value over the long term. The innovative paint system, which was introduced first by the Stuttgart-based automotive brand, is a standard feature of the new S-Class. It is used in both metallic and solid paint schemes.
Remarkable advances in the area of nanotechnology have allowed tiny ceramic particles — each less than a millionth of a millimetre in size — to be integrated into the molecular structure of the binding agent. The nanoparticles provide a three-fold improvement in the scratch resistance of the paintwork and ensure visibly enhanced gloss over an extended period of time.
Aerodynamics: new paragon of the upper-range segment
In recent years, the aerodynamics engineers of Mercedes-Benz have proven many times that they are masters of their craft. The cars bearing the Mercedes star are among the most aerodynamic and responsive passenger cars in the world. With the new S-Class, the Sindelfingen experts achieved another aerodynamic tour de force. Despite the larger tires and wheel housings and the higher demands placed on the engine cooling system and the interior air conditioning, the saloon attains an even better Cd value than the predecessor model: Cd 0.26. That makes the new high-end Mercedes model the shining ideal of the upper-range segment in regard to aerodynamics as well.
The Cd value is the result of painstaking detail work that began long before the construction of the first prototype. Using ultra-modern simulation techniques and models on the scale of 1:4, engineers and designers first developed a basic shape that set the future direction both stylistically and also in terms of aerodynamics engineering. Starting from this basis, there followed additional fine tuning of all the body details, until finally the definitive design of the new S-Class was developed and a 1:1 prototype model also passed its crucial test in the wind tunnel.
From the beginning, the Mercedes engineers carried on their aerodynamics development using the latest measuring methods, which allow a very true-to-life analysis of the airflow conditions on and under the body. Chief among these is the road simulation: All the wind tunnel tests for the new S-Class - from the first 1:4 model to the series-standard pilot production car - took place with moving wheels so that the aerodynamic interplay between road, tires and body could be studied even for high-speed highway driving.
The Mercedes specialists used the insights gained from these series of tests to optimise the form and function of various body elements:
- The front wheel spoilers were extended to reduce the impact pressure of the airstream in front of the tires;
- The three-part lining of the engine compartment was extended to the rear edge of the transmission, ensuring a turbulence-free air flow;
- The panelling of the main underfloor covers the fuel tank too;
- The moulding of the spare wheel well was shaped in such a way that it guides the airflow in the rear upward and improves the “ caster”.
Other body details deserve mention here as well, such as the aerodynamic styling of the front apron, the A- and C-pillars, the exterior mirrors and the boot lid. All of these help reduce drag. The air suspension, which comes as standard, makes a major contribution as well by automatically lowering the body by up to 20 millimetres in two stages at speeds above 120 km/h, thereby reducing drag by over four per cent.
The aerodynamic characteristics of the new S-Class at a glance:
|Drag coefficient (Cd) ||0.26 – 0.28 |
|Front surface area (A) ||2.40 – 2.41 |
|Aerodynamic drag area (Cd x A) ||0.62 – 0.67 |
|Front axle lift (Clf) ||0.06 – 0.10 |
|Rear axle lift (Clr) ||0.09 – 0.11 |
Good aerodynamics contributes to driving safety too
The good lift factors at the front and rear axles show that the exemplary aerodynamics of the new S Class not only enable a new record Cd value but also have a positive effect on driving safety. They are up to 14 per cent lower than the corresponding figures of the predecessor model and constitute reliable indicators of high braking stability, secure road-holding and low crosswind sensitivity.
The aerodynamics also makes an important contribution to road safety through design details that give the driver an unclouded view through the front side windows during rain. The Mercedes engineers achieve this by deliberately guiding the rainwater backwards, downwards or to the side. In the new S-Class, the side windows, mirror glass and door handles remain for the most part clean, because the rainwater hitting the front window collects in run-off tracks on the A-pillars, is led from there backwards over the roof with the help of the airflow, and then flows downward and away in a channel on the trailing edge of the roof. The housings of the exterior mirrors are shaped in such a way that rainwater flows outward and drips away in a narrow surrounding groove.
Aero-acoustics: details crafted for minimal noise emissions
The aero-acoustic properties were a further focus of the work in the wind tunnel. The objective of the Mercedes engineers was to minimize the wind noise that results from the flow of air around the body and its external fittings or from vibrations induced in the body panels. And the Sindelfingen specialists achieved this objective. The new S-Class offers a distinct improvement with regard to noise levels. In fact, it is one of the quietest cars in the world and one of the most pleasing acoustically.
The aero-acoustic experts and body developers worked together closely early on in the concept phase of the saloon and created the structural conditions necessary for a marked reduction in noise levels - for instance, through a more rigid body-in-white, reinforced outer panelling and a new door design with mutually independent inner and outer modules. Starting from this firm foundation, they then successfully optimised details in the wind tunnel.
In the wind tunnel tests, the Mercedes engineers tracked down troublesome wind noise using a newly developed measuring technique: A three-metre-high concave acoustic mirror equipped with several highly sensitive microphones and a video camera scans entire sections of the body and helps localize troublesome sources of noise. At the side windows, for example, the microphones at the focal point of the concave mirror recorded all the wind noise from the entire body, and the sources of noise were represented on a computer monitor in colour according to volume (level) and frequency. Since the camera image is transmitted to the computer at the same time, the positions of critical noise sources can be precisely determined. That makes optimisation measures easier and more effective.
One result of these aero-acoustic measurements using the concave mirror is the housing of the outside mirror. The narrow bridge that connects the mirror housing to the door was designed in such a way that wind noise due to the airflow over the bridge is eliminated or compensated for. In addition, the door gaps are multiply sealed. In important areas, up to four levels of sealing ensure that no wind noise is audible in the passenger compartment. Similarly, the shape of the A-pillars and the special rubber seal between the rear window and boot lid are also a result of the noise analyses in the aero-acoustic wind tunnel. For the tilt/slide sunroof and the new “Panorama” sunroof, the Mercedes experts developed serrated wind deflectors. Their notches generate air swirls running lengthwise, and these effectively suppress the annoying booming noise that would otherwise occur when a sunroof is open.
Windshield wipers: aero-technology with two motors
Mercedes-Benz developed the windshield wiper system of the new S-Class in the wind tunnel also. Hence the name “ Aero wipers”: Instead of the jointed system on which the wiper blade element is hung in conventional wiper blades, the wind-shield wipers of the flagship Mercedes model consist of a single piece of rubber with an integrated spoiler and spring rails positioned on the outside. They ensure an even distribution of the contact pressure. This results in a significantly better wiping effect, and drivers will also notice that the wipers make even less noise.
To prevent the windshield wipers from freezing in place, they are warmed by an electrical heating system when in the retracted position. The four washer fluid nozzles are heated as well.
The windshield wipers on the driver and front passenger side are driven by two separate motors and have different patterns of movement. Whereas the left wind-shield wiper moves on a fixed axis of rotation, its right counterpart also makes a lifting movement in order to clean a large section of the window.
The rain sensor, which controls the windshield wipers in accordance with the intensity of the rain, comes as standard equipment in the flagship Mercedes model and can be adjusted to one of two settings using the multifunction lever on the steering column.
Windowpanes: silver foil as infrared reflector
The new S-Class is typically equipped with green-tinted safety glass when it comes off the assembly line. For Mercedes customers who want even more effective protection against the sun, engineers have developed an infrared-reflecting compound glass featuring an invisible coating of pure silver. It not only filters out the ultraviolet rays of the sun but also reflects the infrared light in the solar spectrum that heats up the passenger compartment. The result is that, compared to glass with a conventional green tint, the overall transmission of energy into the interior is reduced from 60 to approximately 47 per cent, thanks to the infrared reflection at the windshield.
Additional protection from the sun is provided by the blinds for the side windows in the back and the rear window, also available as an option. They are electrically operated.
Sunroofs: open-air effect through Panorama glass plane
In addition to the glass tilting/sliding sunroof with the automatic PRE-SAFE® closure feature, Mercedes-Benz is offering the owners of the long-wheelbase version an extra that guarantees special open-air enjoyment: the Panorama sunroof.
The name can be taken literally, because compared with the tilt/slide sunroof, the glass pane of the new development is almost twice as large - it extends from the front windshield to the rear window of the S-Class. At the push of a button, the front part of the roof rises and shifts backward over the immobile glass section while a glass louver erected in front serves as a wind deflector. As with the tilt/slide sunroof, the movable half of this sunroof can be set at different heights. The Panorama sunroof can also be controlled remotely via the electronic key, as with the conventional version.
Extruded aluminium profiles make up the sturdy frame structure of the newly developed sunroof, which is bonded to the roof frame as a fully prefabricated module. Aluminium mouldings with black paintwork cover the side gap between the body and the glass elements on both sides. The Mercedes engineers use the bridge element midway between the two halves of the roof to accommodate the vanity mirrors for the rear passengers. For protection from the sun, there are electrically operated blinds on the inner sides of both panes of glass. They can be drawn shut or opened independently of one another.
Light: bi-xenon technology in combination with curve and cornering light
The headlamps of the S-Class incorporate state-of-the-art lighting technology and make an important contribution to road safety. For the dipped headlights, high-luminosity halogen projection-beam lights come as standard equipment; separate H9 reflector lights are used for the full-beam lights. The indicator lights and side-lights are likewise accommodated in the elegantly proportioned headlight housing, while the fog lamps are integrated into the bumper fascia. Thanks to the driving light assistance system at the windshield, which comes as standard, the head-lights and tail lights switch on automatically when it gets dark, when rain or snow hinders visibility, or when the S-Class enters a tunnel.
The optional bi-xenon headlights also come with two new lighting features that provide a significant improvement in driving safety after dark:
- The active curve light improves the illumination of the traffic lane by up to 90 per cent. Whereas conventional dimmed headlights are able to provide illumination for a distance of some 30 metres when entering a curve with a radius of 190 metres, the new headlight feature extends this range to about 55 metres. Since the way the light is cast corresponds to the steering angle, the driver sees the course of a curve earlier than when using conventional dipped headlights. The active curve light works when the headlights are set to either dipped or full beam.
- The cornering light is automatically activated when the indicator is switched on or the steering wheel is rotated for a turn. It illuminates the area in front of the vehicle up to 65 degrees to the side and to an extent of about 30 metres. The cornering light thus illuminates areas of the road that remain dark when conventional headlight technology is used during turns. The advantage of this is that it makes pedestrians and cyclists next to the vehicle clearly visible even in darkness. The cornering light also gives drivers better orientation when they take curves at slow speeds (up to 70 km/h). The halogen reflector for the cornering light is located in the housing of the main headlamp.
The equipment package with bi-xenon headlights, curve lights and cornering lights also includes a dynamic headlight levelling control and a headlamp-cleaning system using a high-pressure water jet.
Flashing brake light for preventing rear-end collisions
The tail lights of the S Class are elegantly separated by two chrome-trimmed body-coloured mouldings. They divide the segments for rear fog lamps, indicator lights, rear lights and brake lights.
The adaptive brake light here is a special technical feature Mercedes-Benz has developed to help prevent rear-end collisions: If the driver has to brake hard at a speed of more than 50 km/h, or if he receives support from the BAS Brake Assist in an emergency, the brake lights of the new S Class flash and warn the drivers behind. If the S-Class then comes to a standstill after such an emergency stop, the brake lights once more shine continuously and the hazard warning signal switches on.
Mercedes engineers have tested the effectiveness of this blinking light on the road. The studies show that drivers’ braking reaction time can be shortened by up to 0.2 seconds on average if a blinking red warning light is substituted for a conventional brake light in emergency braking situations. As a result, the braking distance can be reduced by approximately 4.4 metres at a speed of 80 km/h, and by as much as around 5.5 metres at 100 km/h.
The Mercedes experts tested various types of hazard lights for their study. Brake lights that blink four times as rapidly as yellow hazard lights proved to be particularly effective in warning drivers of a possible rear-end collision. The Mercedes study also revealed that activating the hazard lights in dangerous situations had only a minor effect on drivers’ reaction times.
With adaptive control
Crash-responsive NECK-PRO headrests as option
On the outer seats
With automatic belt comfort system
| || |
Driver and front-seat passenger