Mercedes-Benz Ponton
The Mercedes-Benz "Ponton" series are a range of sedans / saloon car models from Daimler-Benz, introduced starting in 1953, and subsequently nicknamed 'Ponton' (the German word for "pontoon"), referring to its ponton styling, a prominent styling trend that unified the previously articulated hood, body, fenders and runnings boards into a singular, often slab-sided envelope. At the time, Mercedes itself did not refer to any of its cars using the nickname. Mercedes stretched the 'Ponton' saloons into a range that became the automaker's dominant production models until 1959. The 1953 Mercedes-Benz W120, marketed as  180, four-cylinder sedans were Mercedes' second totally new series of passenger cars since World War II, following the 1951 introduction of the top of the range W186 Type 300 “Adenauer”, and replaced the pre-war-designed Type 170 and Type 170 S. Contrasting very visibly with the traditional distinct fenders on that body-on-frame model and the ones before it, the 'Pontons' were Mercedes' first monocoque, unitary body production models. Mercedes expanded the base Ponton model into a diversified line, developing multiple series based on the 180, by introducing more engines and stretching the body. Six-cylinder models  received a longer nose, and 'S'-models also a longer passenger compartment, offering more legroom. A six-cylinder coupe and convertible were further derived, and a shortened floorpan of the four-cylinder sedan was also modified to serve as the structure for the Mercedes-Benz 190 SL roadster. The 'Ponton' saloons were the automaker's main production models until 1959, adding up to 80% of Mercedes-Benz car production between 1953 and 1959, with some models lasting until 1962. The range was succeeded by the range of ""Heckflosse"" or "Fintail" models. Design history. Daimler-Benz emerged from World War II as  a carmaker best known in the early 1950s for its expensive Mercedes-Benz 300 "Adenauers" and exclusive Mercedes-Benz 300 S sports tourers. Both were largely handbuilt body on frame vehicles. Its low end was anchored by the dated pre-war designed Type 170. Seeking to expand its production, Mercedes turned toward the unibody concept to design a line of mass-produced cars. Work began in earnest on the pontons bodied cars in 1951, with a design focused on passenger comfort and safety. Head of the design team was Dr. Fritz Nallinger. Styling was headed by Karl Wilfert. Also in  the design team was Béla Barényi, who conceived the passive safety (crash protection) engineering of the body. The first of the 'Ponton' models to go into production was the 1953 Mercedes-Benz W120, four-cylinder, four-door sedan, available as the 180 petrol and the 180D diesel. In 1954 the Mercedes-Benz W180 six-cylinder executive / luxury model 220a was added, developed mostly by stretching the W120's body by , complemented by a new rear suspension. was needed to fit the longer straight six engine block, and longer rear doors benefited legroom in the passenger cabin. In 1956, the six -cylinder model was expanded into an entire range. The 220a was upgraded to become the 220S. A third saloon series, the Mercedes-Benz W105 was created by grafting the six-cylinder nose onto the shorter center and rear body of the four-cylinder. Fitted with a detuned version of the straight-six, it was sold as the model 219. Additionally, new two-door coupe and convertible bodies were offered for the 220S, on a shortened wheelbase. In 1956, the four-cylinder model also received an all new, short-stroke petrol engine option, the 190 (or W121 internally), and in 1957 , the old 1.8 litre in the 180 was replaced by a detuned version of the 1.9 litre. In 1958, the base range was further completed by also offering a 1.9 litre diesel. In 1958, the 220S models were upgraded with fuel injection, and became the Mercedes-Benz W128, or 220SE series. The models 180(D) and 190(D) received further updates in 1959 and 1961. Designed in safety. Austrian-Hungarian engineer Béla Barényi originally invented and patented the crumple zone concept in 1937 before he worked for Mercedes-Benz, and in a more developed form in 1952. Barény questioned the prevailing opinion  until then, that a safe car had to be rigid. He divided the car body into three sections: the central, rigid, non-deforming passenger compartment, and the crumple zones in the front and the rear. They are designed to absorb the energy of an impact (kinetic energy) by deformation during collision. The 1953 W120 "Ponton" partially implemented the concepts of crumple zones and the non-deformable passenger cell into its "three-box design" by having a strong deep platform to form a partial safety cell (patented in 1941). The Mercedes-Benz crumple zones patent (number 854157) granted in 1952, describes  the decisive feature of passive safety. The first Mercedes-Benz car developed, fully using this patent was the 1959 successor, the Mercedes W111 “Tail Fin” Saloon. The 'Ponton's design concept was proven by ADAC crash test facility in June, 2010 when a Mercedes Ponton was crash tested in their Technical Centre in Landsberg am Lech, confirming the existence of the design incorporated into the vehicle. This made for a milestone in car design with front and rear crumple zones for absorbing kinetic energy on impact. The safety cell and crumple zones were achieved primarily by the design of the  longitudinal members: these were straight in the centre of the vehicle and formed a rigid safety cage with the body panels, whereas the front and rear supports were curved, so they deformed in the event of an accident, absorbing part of the collision energy and preventing the full force of the impact from reaching the occupants. Models and types. There were essentially five models of Ponton bodies on four different wheelbases: three wheelbase length saloons, plus a coupe and cabriolet version on a shortened six-cylinder body. Note the "D" designates a diesel engine, and the suffix "b" and/or "c  are body variants introduced after the middle of 1959. The design of the 190 SL roadster differed completely from the Ponton sedans, copying much of the bodywork of the 300SL sportscar, and using the same suspension, but it was constructed on a shortened version of the W121 Ponton floorpan. Models and engines timeline. Sample specifications. A 1957 brochure provides a cross section of Ponton models then available: