| On the IAA in Frankfurter in September 1993 Mercedes-Benz unveiled the study of a future class of vehicles with front-wheel drive, almost ready for production. The ,Vision_A_93" immediately caught the eye of the world demonstrating in an impressive way that the Mercedes-Benz Advanced Design Team were the first to succeed in solving the conflict between the aim of compact exterior dimensions, spaciousness and variability inside and still meeting the high levels of security of a standard Mercedes-Benz in one unique overall concept.
Measuring an astonishingly short 3,35_m a degree of generosity in spatial distribution and easy accessibility of the interior could be realised otherwise only achieved by the grand mid-range saloons. A high level of versatility is another characteristic of the "Vision_A_93": from the comfortable four-seater up to a mini-van with a loading capacity of 1.000_litres all imaginable demands of our customers could be fulfilled. The base of this revolutionary concept of space was a new raised floor assembly which enabled, a convenient side-effect to a certain extent, a degree of crash security that has never been achieved by a compact car before.
The ,Vision_A_93" is more than a mere study of design and technology. It is the forerunner on a new way into a section of the market that had not been defined until then and a guiding star for the development of the future Mercedes-Benz A=class. After the particularly positive response of public and media the search for the convenient future production location was intensified. Negotiations were long and arduous but on December 14th 1993 the choice was made in favour of Rastatt as plant for the production of the new A=class. These third works of Mercedes-Benz, inaugurated in 1992, were therefore given preference to, before the alternative positions in France, Great Britain and the Republic of Czechia.
While the evolution of the A=class went on as planned, the print media and the public were constantly informed about the latest developments - a way of proceeding never seen before in the history of Mercedes-Benz and especially not as long in advance of the start of series production. In August 1994 60 German and foreign specialist journalists were able to test the one-and-a-half million-marks prototype and to convince themselves of the practical usage of the future A=class in everyday-situations.
Two years after the ,Vision_A_93" world premiere the inside concept of the A=class was presented at the IAA in Frankfurt in September 1995 with the total length already 225 mm longer than planned. The availability of space, already quite satisfying before, was increased once more especially in the boot, and the extensive versatility of the interior has been recognised admiringly.
At the same time the ,Forum frs Neue Automobil", a care program ,forum for the new car" was started with the declared aim to provide the interested public with current information about everything concerning the A=class.
Another announcement made at the IAA was the declaration to expand manufacturing from the Rastatt location and to build up for this purpose additional production capacity in Brazil. Construction started half a year later after corresponding contracts had been signed in Brasilia on April 19th 1996. From the end of 1998 on 70.000 units per year are going to be produced by 1.500 employees for the South-American market.
On may 20th 1996 the A-class entered again the stage of public interest when a PR- and communication-campaign was lanced throughout Germany and six other European countries with TV spots, and advertisements in the print media and the Internet. The reason for this early beginning was the understanding that interested people are occupied with the purchase of a car as early as 12 to 18 months in advance. As the new A=class is a creation within an entirely new category of vehicles and potential clients could not refer to any other previous model it was the more important to create a certain familiarity between the people and the future product.
Shortly before, the W_168, as the A=class is called on the internal level of Mercedes-Benz, had proven in several different crash tests performed at the engineering centre in Sindelfingen that a compact car with only short deformation distances is able to comply absolutely with the high safety standards of Mercedes-Benz. It has become possible through the revolutionary new sandwich structure of the bodywork built of two levels laying on top of one another. The upper part constitutes the passenger compartment whereas the drive-aggregate is located in front of and under the intermediate floor. In case of a front collision the drive unit slides along an oblique splash wall under the passenger cell and therefore cannot be of any harm for the occupants.
But the A=class does not only fulfil the future European regulations for a frontal impact but complies as well with the rigorous U.S. American and European guidelines for lateral collisions.
The first official information and photos of the definitive stock version came to the press in the beginning of December 1996 and three months later the A=class had its world premiere on the Geneva Automotive Salon. It was this event, two months after the presentation of the CLK in Detroit, that marked another milestone in the Mercedes-Benz Passenger Car Division's productive offensive
More than 20 technical innovations which weren't existent in this car category before have been developed in the new model line. Thanks to the unique sandwich principle the A=class reaches the level of a mid-range saloon in the disciplines safety and comfort.
The innovative rear seat accommodation and the passenger seat with the option to be dismounted offer the variability of a mini-van and the possibility of to change the five-seater into a one-, two-, three- or four-seater. All in all there are 72 versions of seat arrangement realisable and concerning luggage storage it reaches the dimensions of large estate cars: depending on the position of the rear seats the a loading capacity reaches from 390 to 1.340_litres and with the passenger seat taken out even 1.740 litres. The even floor, the large hatchback and the low luggage-compartment sill facilitate the loading of the boot.
The stable floor assembly of a compound of straight frame side rails and transverse members is an integer component of the innovative safety system. At the front end of the frame side rails there is a new kind of front module of aluminium with two lateral crash boxes. They are fixed by two screws to the longitudinal beams and are relatively quick and inexpensive to replace after an accident. The front mudguards are made of synthetic material, the first time in a large series at Mercedes-Benz taking again its original form after a light collision without requiring neither repair nor painting. The hatchback is equally made of synthetics for reasons of weight reduction. The repair-friendly construction of the A=class does not only reduce the overhaul after an accident but results as well in a more favourable classification in the third-party, fire and theft insurance.
Concerning the passive security the new model line almost reaches the level of the exemplary E=class. Apart from the unique sandwich principle this is also thanks to the restraint systems specially adapted for the A=class structure with its short deformation distances which are part of the standard equipment. Elements of this system are full-size airbags for driver and front seat passenger, automatic seat belts supplied at the front seat and the lateral rear seats with the seat-belt tighten system and at the front seats with a seat belt load limit-system.
As the engine and the gears of the A=class are fundamental components of the room- and safety concept the development of the drive unit had to follow new ways. Not only the displacement category but also the dimensions and the fitting position of the engine make the traditional choice from the modules in the construction kit impossible and require an entirely new construction. Like this a completely new-fashioned generation of four-cylinder engines with light-alloy block was created: two petrol-engined cars in the construction series_M_166 and two turbodiesel of the construction series_OM_668. All four engines have been made 25_% lighter than any other four-cylinder in the same displacement category by consequent weight reduction. The drive unit is installed directly beneath the pedal floor at right angles in inclined position. The top of the drive block facing the passenger-compartment floor has a smooth surface so that the engine-gearbox assembly can slide downwards along the pedal floor in case of a frontal impact
The Otto engines were already available at the beginning of batch production and performed 60_kW (82_hp) and 75_kW (102_hp) from a displacement of 1.4 and 1.6 litres respectively. The ignition engine with 66 kW (90 hp) and 44_kW (60_hp) is characterised by the four-valve technique, supercharger and electronically controlled fuel injection according to the Common-Rail-Procedure and are planned to be lanced on the market in spring and autumn 1998. Both versions have a displacement of 1.7 litres and in the power-reduced and consumption-optimised version with 44 kW the quantity of fuel to be injected is reduced, the supercharger is adapted to the modified conditions and the charge=air cooler.
To distinguish the models equal in displacement the performance-reduced version is offered as_A_160_CDI.
The Common-Rail technique, developed in collaboration with Bosch, had its world premiere with the two direct injection engines which were presented in Geneva as A_160 and A_170_Turbodiesel and received the abbreviation CDI only in November 1997. While the traditional systems create the pressure for every injection event anew, the CDI motors work through one common line (Common Rail) saving the pressure and distributing it via magnet valves to the injection nozzle. The high injection pressure of up to 1350 bar, available already at low rotational speed, as well as the variable control of the injection process result in a considerably improved mixture formation leading again to a high torque, low fuel consumption and less exhaust emission. However, the first application in series of this highly modern Diesel technology took place in the C=class, when, in December 1997 the first copies of the C_220_CDI, presented two months earlier in Frankfurt, came to be delivered.
Another novelty, the Active Service System ASSYST, analyses the oil quality in the engine constantly and enables all A=class engines to sense what are the engine's needs and matching exactly the frequency of service checks or oil changes. It thus keeps the trips to the service bay to an average of every 40.000_km. The innovative four-cylinder aggregates are produced in the works in Untertrkheim where passenger car engines have been produced since 1904.
Similar to the engines, the gears of the A=class are newly developed, adapted with their inclined exterior surfaces to the existing concept of bodywork and safety. The five-speed manual transmission which is part of the standard equipment weighs only 32_kg and is therefore the lightest gear of its torque category. Another technical milestone among the new models is an electronically controlled 5=speed automatic gearbox that can be delivered on demand from spring 1998 on. The particular novelty is that it is with only 315_mm in length and 68_kg weight the shortest and lightest automatic 5=speed gearbox.
The automatic clutch, having its premiere in the A=class, is a quite inexpensive alternative to the automatic gearbox. The moment the driver takes the foot off the accelerator and moves the gear lever the system recognises the intent of shifting gears and opens the clutch via an electric motor.
The chassis of the A=class is equally a novelty. The traditional constructions could not be used, as they could simply not be made to fit in the innovative concept of room prevailing in the A=class. In the front a modified McPherson system with helical springs, double-tube gas-pressure shock absorber and torsion-bar type stabiliser are used. The axle components are fastened to the integral beam, which is fixed by screws to the body at eight points, together with the rack-and-pinion steering gear and the engine-gearbox assembly. In the rear a trailing-arm axle with helical springs, single-tube gas-pressure shock absorber and torsion-bar type stabiliser are used. This axle construction can be installed below the loading floor without cutting back space in the car's interior. The shock absorber and suspension are located in a section in front of the wheel's centre that would otherwise remain unused.
Power steering is a standard in the A=class and works with an electronically controlled pump with adaptable performance. For the case of a flat tyre the car is provided with the tyre sealing solution TIREFIT which is part of the standard equipment in Germany plastering the tyre for the drive to the next station. An electric air pump is also part of the system that is connected to the board net via the cigarette lighter. Alternatively there is a spare tyre available on demand without extra charge.
The idea of offering different design- and equipment lines that has proven its success in many years is also realised in the A=class. The offer comprises the three versions ,Classic", ,Elegance" and ,Avantgarde" having in common a rich standard furnishing. The ,Elegance" version offers several additional features not only regarding the interior, but also visible in the external appearance compared to the basic ,Classic" version. Among those are the light-alloy wheels, the radiator grille and the outside rear-view mirror housing finished in the body's colour, chrome trims in the door handles as well as bi-coloured rear light glass. The ,Avantgarde" line, technically seen the most progressive version, is characterised by light-alloy wheels with wide-base tyres, a silver finish on the radiator grille, the outside rear-view mirror housings painted in the body colour and the rear light glass in single colour.
Sales of the new A=class was started on May 5th 1997 after the prices had been announced on April 30th. Within a short period the entire production of the year was sold out and potential new clients were forced to come to terms with delays in delivery quite soon.
In September 1997, four years after the study ,Vision_A_93" was presented, the stock version of the A=class was unveiled at the 57. International Automobile Exhibition in Frankfurt for the first time in the three available design- and equipment-lines. In the same month the main series production of the petrol-engine types A_140 and A_160 began in Rastatt. The third passenger car production plant of Daimler-Benz manufactures the A=class in collaboration with six other German firms: sheet-metal panels are ordered from Sindelfingen, engines, gearboxes, front axles and drive shafts from Untertrkheim, oil and water pumps camshafts and crankshafts from Berlin, differentials from Kassel, steering systems from Dsseldorf and finally rear axles, column tubes, exhaust manifolds and lever-type hand brakes from Hamburg.
The bodyshell is manufactured out of 290 single tinplate pieces with 3.700 welding points to make a perfect A=class bodywork. It is then painted using a unique procedure that is characterised by its high environmental compatibility, efficiency and quality.
The key part of this fully automatic process that has been developed in a co-operation with the partners at BASF and Drr Systems is the integrated painting idea that made it possible to skip the filler coat, the Pulver=Slurry process for solvent-free clear coat finish as well as a new corrosion preventive procedure omitting the body-cavity sealing.
The final introduction in the market was on October 18th 1997 when the A=class was unveiled before the public at the Mercedes-Benz agencies and sales partners. The first cars were delivered only a few days later to the clients. The development, followed attentively by the public for more than four years, has been brought to a first end - at least that is what it looked like.
Only a short time later the unexpected happened: The A=class overturned in the course of an extreme driving manoeuvre in Sweden on October 21st which caused a great stir in the around the world menacing to harm the image of the new product and even the entire brand of Mercedes-Benz lastingly. The driving manoeuvre known in Sweden as the ,moose test" and the extreme version of which - with full load and at high speed - has become the undoing of the A=class soon showed to be the talk of the town.
An international press conference held on October 29th in Stuttgart did not bring a relaxation of the situation at first, but provoked new attacks after the European media had carried out in the mean time more or less professional own tests with varying results. Neither the attestation of the technical inspection ,TV Sdwest" who certified the A=class that it fully complied with the safety standards after they had tested the A=class on October 26th under standard- and reproducible conditions nor the decision of the Daimler-Benz management to equip the driving dynamic system ESP as a standard.
On November 5th the ADAC finally concluded after extensive examinations that the A=class succeeds just as well in the tests as all the other models in the vehicle's category. In the meantime the engineers and technicians of the passenger car development department were preoccupied with ever new tests to find the chassis and suspension tuning with which the A=class would hold its ground even in only little practical conditions.
The discussion that had become more and more emotional in the meantime finally turned more reality-oriented on November 11th when Jrgen E. Schrempp, director of the board of the Daimler-Benz AG, presented the solution. The experiment and development engineers have optimised the chassis and suspension tuning and had thereby found the solution to improve driving condition in extreme situations.
These results were now to be realised as quickly as possible in the production. The modifications ranged from new stabilisers to new suspension- and shock absorber tuning at the axles, lowering the bodywork as well as using wider tyres. In addition to this the engineers wanted to go one step further and implement the refined ESP in the A=class as a standard. With this concept of a chassis the A=class will even overcome extreme situations in the real life traffic situation that no other car of this category would be able to master: on snowy, icy and wet road.
In order to be able to realise the new concept in the main batch a preparation period of 12 weeks became necessary, a period that meant necessarily an interruption in the delivery of the car. The 2.600 units that had already been given over to the clients are fitted in special extra service centres. The customers concerned have been offered to hand in their A=class and to take in the meantime another model of Mercedes-Benz.
Rather unspoilt and notwithstanding the events, the A=class was awarded two very popular prizes on November 10th and 12th. On November 10th the board member Jrgen_Hubbert received from the hands of the Austrian chancellor Viktor_Klima the Austrian automobile award ,Groáer sterreichischer Automobilpreis 1997". Two days later the A=class was awarded the ,Goldenes Lenkrad" (golden steering wheel) by the popular tabloid ,Bild am Sonntag" in Berlin. In both cases the decision of the jury had been made before the incident in Sweden. But none of the jurors on the board of the Austrian prize drew back their vote for the A=class after the events concerned.
The jury of the ,Goldene Lenkrad" have agreed with Daimler-Benz to have another test with an A=class fitted with the ESP system performed by a special expert of the jury to be on the safe side. The rally professional Rauno Aaltonen drove the A=class 38 times through the ,moose test" and a normalised slalom-test at different speeds above the required 60_km/h and with various loading. The car proved in all test courses to be particularly smooth, secure and manoeuvrable without problems. The integrated ESP showed its efficiency in an impressive manner. When Aaltonen wanted to provoke critical driving conditions this was prevented by the electronic system at the first signs already.
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