[Citroën innovations] Citroën DS: The secret of the directional headlights from 1967

Citroën DS: The luminous innovation of swiveling headlights

We continue our series dedicated to the legendary innovations of the "Double Chevron" brand. Today, we focus on a technological breakthrough that, twelve years after the Citroën DS's initial debut at the Grand Palais, allowed the model to pull ahead of its rivals once again. In 1967, while the automotive industry relied on static lighting, Citroën introduced swiveling headlights, giving the DS the unique ability to illuminate areas where its competitors remained in the dark.

1967: The face-lift that gave the legend a new gaze

In September 1967, the Citroën DS underwent its most significant aesthetic evolution since its launch in 1955. Designed by Flaminio Bertoni, the front end was completely redesigned. The fenders, hood, bumpers, and lower fairing were modified to integrate a new four-headlight optical block housed under a streamlined glass cover. This visual change gave the car a more modern, sleeker, and more dynamic appearance.

However, the brand did not stop at a mere cosmetic update. With this restyling, Citroën introduced a directional headlight system, fitted as standard on Pallas trims and available as an option on other ID and DS models. This innovation was not a gadget but a concrete response to road safety challenges. By allowing the light beams to follow the wheels' path, Citroën provided drivers with optimal visibility in curves, further cementing its status as a visionary manufacturer and the mythical character of the DS.

The engineering of the "gaze": how the system works

The DS swiveling headlight system is a fascinating example of Citroën's philosophy: a mechanical solution of formidable efficiency. Unlike the complex and expensive electronic systems developed at the time by suppliers like Cibié, engineer Paul Magès opted for an approach based on cables and linkages.

The device relies on the lateral movements of the steering rack. A linkage system consisting of levers and rods, equipped with return springs, transmits the steering angle to the two inner spotlights (the 162 mm iodine lamps). The genius lies in the asymmetrical movement: the headlight on the inside of the turn pivots more than the outer one. When the wheels are at full lock, the inner headlight can reach an angle of nearly 80°.

This design allows for anticipating the trajectory. By eliminating the response delay caused by tire elasticity, the headlights illuminate the inside of the curve before the vehicle even begins to turn. In the "high beam" position, all four headlights work together, ensuring perfect lighting of the landscape and eliminating the "black hole" effect at the exit of a curve. The gain in preventative safety was estimated at the time to be between 20% and 30% compared to traditional lighting.

The DS: confirming its lead over the competition

With the introduction of this innovation during its face-lift, the DS reinforced its image as a rolling technological laboratory. From its release in 1955, it had already disrupted the industry with its hydropneumatic suspension, high-pressure braking, and power steering. In 1965, it had already received "dynamic" headlights capable of adjusting vertically to compensate for the car's pitch variations.

The addition of swiveling headlights in 1967 allowed Citroën to maintain a spectacular technological lead over its rivals. While other manufacturers struggled to provide satisfactory lighting in a straight line, the DS could "see around corners." This ability to anticipate danger and offer unmatched night driving comfort transformed road conditions. As observers of the time noted, the DS seemed "alive," its eyes following the road to serve its driver.

Conclusion: a legacy of design and function

In conclusion, Citroën proved with the DS restyling its immense talent for merging design and functionality. By brilliantly updating an already legendary model to integrate swiveling headlights, the brand extended the DS's career while asserting its technological superiority. Twelve years after its birth, the DS achieved the feat of distancing its competitors once again. By refusing to do "like everyone else," Citroën permanently etched the innovation of directional headlights into the history of the global automobile.