This Traction Avant tours around Chicago, old-time gangster city.

First, before the DS, there was the Traction Avant, the TA.

After the economic crash in New York in 1929 and the crisis that followed in Europe, the high-priced Voisins didn't sell anymore, and Voisin skidded into financial difficulties. Lefebvre had brilliant ideas for an altogether new kind of automobile that Voisin could no longer build. It was the end of their road together. Lefebvre had to move on. 
Lefebvre looked for new opportunities to realize his ideas. He failed to win the support of Louis Renault. Then, making a decision that would change automotive history, Renault's arch rival André Citroën said, "Oui!" 

Citroën and Lefebvre envisioned building a totally new kind of family automobile, a strong, low car, with independent suspension, better stability and road holding and front wheel drive. This was in a time when only one percent of the cars had front wheel drive, and they were race and sports cars. 
As designer of aeroplanes Lefebvre had a wholly different way of looking at wheel-road contact. He foresaw that roadability could be much improved. To get his company out of the red into which it had slipped and back on the road, Citroën desperately needed a sales success.  

Both men wanted to show the motoring world that front wheel drive was a better proposition. To make manufacturing the new concept viable Citroën would have to step up to mass production. Next move: a visit to Henry Ford with whom he got along quite well. From there they went to see Budd, a manufacturer of steel stamping presses for car panels. By 1916 Budd was already producing steel bodies for Dodge and German customers, Adler, Audi, BMW and Wanderer. The new Citroën was to be a superior automobile, a wholly welded monocoque construction. The expense of the Budd presses was enormous, but since they could turn out much larger runs of cars than traditional methods, the investment was economically feasible.

The new Traction Avant was developed at a fast pace, but Citroën's grave financial problems necessitated too fast an introduction; the TA was only at the borderline of full development. Lefebvre had proved to be an excellent team manager, and although it was definitely too late, he solved all the problems in the end. 

The spiritual and technical father s of the TA were André Lefebvre and Flaminio Bertoni, who as automobile sculptor gave the car its incomparable, characteristic modern form. He came to work with Citroën and in one night modeled the Traction in plasticine. For the first time a car was not sketched on paper but designed directly in three dimensions.
The engine had overhead valves, and far ahead of its time, replaceable cylinders. The TA featured Lockheed hydraulic brakes and from 1936 onwards a rack and pinion steering mechanism. All these innovations would be adopted by other carmakers, but only years later. 
The high production volume meant that the TA had to appeal to a wide public. A variety of models was built next to the standard four door model:  the wider and larger Normale; the Roadster; the Faux Cabriolet, and the longer Familiale with six side windows and strapontins, fold-up seats between the front and back seats. Variations of the Familiale included the Commerciale with a large hatchback, and a Limousine available without the strapontins. The 15-Six, introduced in 1938, had a 2867 cc six cylinder engine. A 15-Six, custom built as a roadster for Madame Michelin, later came into Dutch ownership. The 7-series was in production until 1940. At the outbreak of the Second World War in 1939 production of the Traction Avant essentially came to a standstill. In 1945 production resumed at the rate permitted by the availability of scarce materials. 
At first, o nly the Légère and the Normale were obtainable, and only in the most spartan version s . The cabriolet and coupé models did not return. Not until 1953 did production of the Familiale and Commerciale resume . During the 23 years' lifetime of the production run not much was changed. In 1952 the spare wheel moved from its mount on the outside of the trunk to the inside. The waveform bumpers were straightened, and the wipers changed place from the top of the windscreen to the bottom. The front seat became Pullman seats. The drive train at the front was modified. All other attention and energy was invested in the new, forthcoming model, the DS. 

Gangster get-away-car.
The Traction Avant 15/Six could reach a high for the time top speed of 130 km/h, and had fabulous road manners that impressed us in the classic gangster movies. The 2867 cc 6-cylinder engine's 77 hp made her the ideal get-away-car, but she was also called la Reine de la Route, the Queen of the Highway. Gendarmes driving 4-cylinder models tried to catch the thugs, but never succeeded, giving Jean Gabin and his mates the opportunity to turn up in the next movie. In contrast to these breathtaking scenes in black and white, my DS flew low above the ground through endless, waving green fields.

Hydro-pneumatic suspension.
In 1954 Citroën introduced the new 15-Six H - Hydraulique - equipped with hydro-pneumatic suspension on the rear wheels, a foretaste of the sumptuous ride to come in the DS. And the Traction could be bought in more colors than black; two shades of grey or two shades of blue.
Motoring journalists had hoped for a completely new model. Instead, they were toured around in the Hydraulique, fêted with champagne at speed while no drop was spilled. This astonishing demonstration was reported with great enthusiasm by the press, and 3000 Hydrauliques were built. 

At last, in 1955, the successor to the TA was introduced, the most revolutionary automobile of all times, the Citroën DS19. (For two years, TA production would continue. Number 759.123 rolled from the factory in July 1957. But love didn't die. Until this day many Tractions keep rolling.

The HY.

First came the Citroën TUB, Lefebvre's creation that we now refer to as a wingless Junkers, the German Auntie Ju, a tri-motor aeroplane made of corrugated aluminum. We've seen the HY along Belgian and French roads as movable chips parlors. The Citroën HY was produced between 1947 and 1982 and is still highly regarded for its technical characteristics, and its distinctly non-bourgeois style. For 34 years the HY remained practically unchanged, an absolute record for a van. In total 475.000 were produced. 

Although the HY was to be much more voluminous, the brief was more or less identical as for the 2CV: front wheel drive, low fuel consumption, good road holding. The blueprints were ready during the Second World War, but the first prototype was completed when the war was over. All technical components were built in a unit up front: engine, gearbox, differential, and drive shafts. The body was built on a separate chassis so it was easy to make the van longer. The HY was built in hundreds of variants, as an ambulance, a fire-fighter truck, camper, removal van, a workshop, a sales van, et cetera.

Characteristic photo, DS powerfully accelerating.

The DS.
When André Lefebvre drove the first DS along the Avenue des Champs-Élysées on the 5th of October in 1955, it caused a commotion as in the days of the revolution. Exceeding the wildest speculations the DS proved to be the most revolutionary automobile in history. The Citroën DS moved above the road as if suspended by some unearthly means, it literally floated. La Déesse, the Goddess of the Road. In Holland she was soon called the Pike or Flatiron. Haifisch in Germany. Tibúron in Spain. Squala in Italy, Padde in Flanders, Belgium and Norway. 
The next day the DS was presented at the Parisian autosalon with the impact of a blockbuster bomb, 'La Bombe Citroën'. With its totally new driving characteristics and technical advances never seen before in an automobile, the car was a sensational surprise. On the first day of the salon 12.000 sales orders were taken. By the end of the week 80.000 sales had been booked, which caused serious production problems for the factory. On the River Seine a DS floated on four big red spheres, symbolizing the hydraulic suspension... science fiction... a legend from the future... Jules Verne! Deliveries could only begin during 1956, a disappointment for buyers; many cancelled their orders. At the end of 1956 an economy version was introduced: the ID19. The ID and DS became available in various models, a Berline, a Sedan, a Break and a Cabriolet.

Riding on balloons, moving on flying carpet.
The TA Hydraulique had already given an inkling of what was cooking in the hydraulics area. And it was generally assumed that the forthcoming car would be equally innovative in all its engineering. Steering system, brakes, gearbox and clutch harmoniously blended together in an entirely new system. A classic gearbox was hydraulically operated at the touch of a butterfly light shift lever. The car was fitted with disc brakes at the front and drum brakes at the rear. The essential technological masterstroke of the DS is the hydro - pneumatic suspension. When the engine is started the DS rises to her driving mode, and when the engine is stopped she sinks back down. For its time, the hydro-pneumatic suspension offered ideal suspension characteristics: the suspension becomes firmer as the load increases. A DS will never 'bottom out'. Ride height can be adjusted manually; the car will automatically maintain the selected height. It's odd to see passengers get in: the car gently lowers itself, then as the system adjusts, it returns to the initial height, the front independently from the rear. This feature makes the DS ideal for towing a caravan, since in spite of the weight she remains flawlessly horizontal. Equally notably, changing a flat tyre is unbelievably easy: place a little pedestal under the body next to the flat, press a button and the wheel rises off the ground.
The unique body style is the end product of cutting-edge research to find a form with the lowest possible air resistance. The wide, sleek nose, the sloping roofline, a body that tapered 20 centimeters from front to back blended into a shape unlike any car ever built except, perhaps, the Laboratoire. 
DS drivers enjoyed stable road holding thanks to front wheel drive, a very low centre of gravity on a long wheel base (3.125 meter), and a highly unusual weight distribution that put twice as much weight at the front  as at the rear. Dynamically, the DS behaves like a hammer flying through the air, with the heavy steel head up front. The gigantic wheelbase gave passengers utterly spacious legroom. New materials were used in the interior, such as rayon (Helanca) for the seats, and nylon for the dashboard, the largest part ever made in one piece.
Merely sitting behind the steering wheel of a DS one becomes immediately aware of the advanced nature of the vehicle. The large, slim rimmed wheel has a single spoke - unique at the time, unique today! The wheel allowed an unimpeded view of the dashboard gauges; it was also cheaper to make than conventional wheels.

A capsule chock-full with innovations.
In general the DS is regarded as the most innovative post-war automobile, and   many authorities see it as the most revolutionary car of all time. In September, 1967, the single headlamps were transformed into double headlamps behind streamlined glass covers. The high-beam lamps turn into corner s in union with the front wheels. The DS is the first car with disc brakes, and the first car with a curved windshield, with pillars thinner than the distance between the eyes, effectively omitting the blind spot. The DS was far ahead of her time, and while the pack has had fifty years to catch up with the tech nology, its suspension remains incomparable. Another of its idiosyncratic, fantastic features is the brake system that automatically adjusts and regulates the brake power according to the division of the car's load between the front and rear wheels. The brake pedal was an odd mushroom, that only needed to be depressed a few millimeters, so the heel could remain on the floor as the foot moved from the loud pedal to the brake pedal, tiny detail that offered extra split seconds of life saving time.
Gabriel Voisin built automobiles based on his experience building aeroplanes; likewise André Lefebvre built vehicles developed in a brain that drew its inspiration from the sky. At Citroën their dreams were realized through the design genius of sculptor Flaminio Bertoni and by the entrepreneur ship of the style conscious daredevil boss Pierre-Jules Boulanger.

Till the end of his life Lefebvre was a lateral thinker.
In 1958 André Lefebvre was struck by a paralysis of his right side and forced to stop working. He had problems speaking, but with enormous will power he taught himself to draw with his left hand. He retreated to his home in l'Etang-la-Ville and started creating again, new and unique ideas. Till the end of his life, till his death on May 4, 1964, he was still the brilliant lateral thinker and automotive designer, still seeing far ahead of his time.

DS and recent successor C6.

In Paris a DS floated on the River Seine on voluminous red spheres instead of wheels, an allegory for the hydro pneumatic suspension. She looked like a s paceship that had come from the moon. La Bombe Citroën she was called, and La Deësse.