It comes with a fragrance dispensing system borrowed straight from the S-Class.
Shortly after coming out with the Mercedes-Benz Tourismo RHD, Daimler has another all-new bus to showcase. This time around, it comes from Setra and takes the shape of a double-decker with a segment-leading drag coefficient of 0.35. Buses will forever and ever be boxy in order to maximize space inside the cabin, but even so the advancements made in aerodynamics are making them sleeker and sleeker with each new generation. It wouldn’t be entirely accurate to say it’s as aerodynamic as a Focus RS (also with a Cd of 0.35), but even comparing the two is an achievement in its own right.
While it’s a tricky job to try and make a box on wheels look nice, Setra has found a way to give the new S 531 DT a really cool design, especially in this “Viola Pyxis” shade. Sure, it’s no Jaguar E-Type, but it might just be the E-Type of double-deckers. We’re exaggerating to prove a point, of course. The new 14-meter bus belongs to the TopClass 500 family and offers seating for up to 83 passengers along with their luggage thanks to a gargantuan cargo capacity of 8.4 cubic meters (296 cubic feet). It features everything you could ever imagine to see in such a large vehicle, from a kitchenette and a washroom to numerous underfloor stowage compartments and a toilet compartment.
Double-decker drivers will be happy to hear there will be fewer visits to the fuel station should they have the privilege of getting behind the wheel of Setra’s latest gem. That’s because the capacity of the diesel tanks has been enlarged from 510 to 540 liters compared to the previous S 431 DT, which has been in service since 2002. There’s room for an optional tank providing an extra 170 liters or even 270 liters for those really long journeys. These upgrades were possible by moving the main switch panel for the electrics next to the entrance at the front on a sliding base while the compressed air tanks have been relocated below the driver’s platform and in the section of the rear axles. The spaces freed up on the left side of the bus have now been occupied by the diesel tanks.
Setra has done the math and estimates the S 531 DT will save approximately 3,000 liters of fuel compared to its predecessor if driven annually for 100,000 kilometers (62,137 miles). This will be possible not just thanks to its more fluid shape, but also because of the latest six-cylinder, 12.8-liter diesel engine producing 510 horsepower (375 kilowatts) and 2,500 Newton-meters (1,843 pound-feet) of torque from just 1,100 rpm.
Another ace up its sleeve is a feature borrowed straight from the Mercedes S-Class. An optional fragrance dispensing system kicks in when the bus’ ignition is turned on and one of the doors is left open. The logic behind this is to make sure those boarding the double-decker will be greeted by one of the six perfumes available.
Having to carry 83 passengers, it goes without saying safety is of utmost importance. Setra’s new S 531 DT is actually the first bus in the world to boast Active Brake Assist 4 brakes with pedestrian detection. Not only does it alert the driver of an imminent impact with a pedestrian, but it also automatically applies the brakes. Its long-distance radar mounted at the front can spot any obstacles up to a distance of 250 meters (820 feet) while pedestrians are spotted up to a distance of 80 meters (262 feet). As for motorcycles, mopeds, and cyclists, the radar will notice them from a maximum distance of 160 meters (524 feet).
Another first in the bus segment is the Sideguard Assist borrowed from Mercedes’ trucks and can be shortly described as a clever blind spot system. It warns the driver whenever something is going on the bus’ sides while making a turn or changing lanes.
The new Setra double-decker builds upon the success of three previous generations kicking off with the S 228 DT launched back in 1981. Since then, combined sales have racked up more than 4,000 units.
Gallery: 2017 Setra S 531 DT
Maximum efficiency, variability, comfort and safety, exciting design: world premiere of the new Setra S 531 DT double-decker bus
- Safety: world premiere for Active Brake Assist 4, Sideguard Assist in the bus and coach segment
- Efficiency: outstanding aerodynamics lower fuel consumption
- Variability: the new Setra is a bus to meet all needs
- Comfort: bright interior, convenient stairs, innovative washroom
- The Setra double-decker bus is "heaven-scent"
- Design: modern and surprisingly distinct appearance
Maximum efficiency and variability, supreme comfort and the ultimate in safety: the new Setra S 531 DT double-decker bus of the TopClass 500 sets new standards in its class. With superlative aerodynamics, this impressive touring coach is all set to establish new fuel efficiency records in its segment. With its flexible lower deck, it covers the entire scope of applications in touring and regular services. The interior boasts an impressive standard of comfort. Finally, the use of Active Brake Assist 4 and Sideguard Assist on board the new double-decker bus will mark the world premiere for these assistance systems in the bus and coach segment. These systems further enhance the already high standard of safety. All this is cloaked in a fascinating design with its own distinct stamp.
Safety: world premiere for Active Brake Assist 4, Sideguard Assist in the bus and coach segment
The very highest safety as standard – courtesy of Daimler Group technology. The premium brand's new double-decker comes as standard with long-life LED headlamps which are kind on the eyes. The emergency braking system Active Brake Assist 4 (ABA 4) is being introduced in the bus and coach sector for the first time ever on board the S 531 DT. In addition to the previously available functions – maximum full-stop braking in response to stationary objects and obstacles moving ahead of the vehicle – it now also incorporates pedestrian detection with automatic braking response. Another world premiere in the bus and coach segment is the use of Sideguard Assist on board the new double decker. This employs radar sensors to monitor the lane to the right of the bus along the vehicle's entire length. When turning off and cornering, it warns the driver of pedestrians, cyclists and stationary obstacles in the turning path. Outside of built-up areas, it additionally serves as a lane-changing assistant.
Efficiency: outstanding aerodynamics lower fuel consumption
The new double-decker bus is tailored for optimum aerodynamics from front to rear. At the front, windscreens with pronounced curvature and large edge radii allow the air to flow around the vehicle, while at the rear recesses and airflow breakaway edges guide the airflow in a controlled manner. The development engineers have attended to the most minute details: the windscreen wiper on the upper deck is vertical in its rest position, for example – a feature adopted from motorsport. These measures result in a drag coefficient of Cd = 0.35 - a new benchmark for this segment. The aerodynamics provide the basis for record-breaking fuel consumption, which drops by around seven to ten percent compared to the predecessor model, according to the type of use. Depending on the mileage covered, this adds up to savings of several thousand litres of fuel annually.
Variability: the new Setra is a bus to meet all needs
Holiday travels, long-distance regular services, stylish bistro buses, inter-city lines – the new Setra covers all conceivable types of use for a bus on this scale. The variable lower deck provides the basis for this versatility, together with the scope for individual appointments and seating which is typical of the brand. Thanks to a completely new construction, the platform on the ground floor on the right as seen in the direction of travel can be omitted if the customer so desires. This results in new options: wheelchair bays, installations for bistro buses, a demountable platform with pram area for inter-city lines or, with platform, the classic seating for touring purposes. The available diversity is also manifest in the cockpit: customers can choose between the elegantly functional cockpit from the Setra ComfortClass 500 and the luxurious cockpit from the TopClass 500.
Comfort: bright interior, convenient stairs, innovative washroom
With a bright interior, with plenty of light and a modern design, the interior of the new Setra makes a spacious impression. The stairs connecting the lower and upper deck catch the eye in particular. Glazed on the outside, they feature panelling consisting of translucent acrylic plastic on the inside. Evenly spaced two-tone steps with individual lighting, landings and continuous handrails give passengers a sense of security when going up and down the stairs. The washroom in a totally new design is also worthy of note. Its installations are arranged diagonally, making maximum use of the available space. The gleaming white upper areas of the furnishings and the pleasant LED lighting are reminiscent of a modern bathroom.
The Setra double-decker bus is "heaven-scent"
An optional fragrance dispensing system takes the already pleasant climate on board the new Setra to new heights. When the ignition is turned on and door one is opened, or when a door is left open, a fragrance generator automatically dispenses a discreet and unobtrusive yet highly pleasing scent. In this way, a fresh yet unobtrusive aura welcomes guests on board and encourages them to feel at their ease. The main components have been taken from the Mercedes-Benz S-Class. There are six fragrances to choose from, ranging from fresh and sporty to a heavier scent that reminds one of leather.
Design: modern and surprisingly distinct appearance
The new double-decker bus belongs to the Setra TopClass 500. Within the 500 model series, it is nevertheless in a class of its own, on account of its broad spectrum of applications and its diverse scope of equipment and variants. This is documented by its modern and distinct appearance. The Setra's face with its dark front panel and silver brand lettering clearly originates from the TopClass 500. As a new feature, the two windscreens are seamlessly joined together and structured by an aluminium bar. On the side wall, the designers have adapted the brand's hallmark "La Linea" aluminium strip, which now extends horizontally along the edge of the roof. The extensive glazing is highlighted by a counter-sweep at the level of the rear stairs, which adds a dynamic touch and features an aluminium surround. The panelling of the upper deck now appears to hover like an island on the glass. Underneath, an aluminium badge above the front wheel arch provides a break in the waistrail on the lower deck. Side fins with airflow breakaway edges and the tail lights of the 500 model series frame the rear end. On the new double-decker bus the two vent grilles for the engine have been joined together. Above these, the black grille of the integrated TopAir air conditioning system makes its mark. The chrome-plated badge featuring the brand lettering from the TopClass 500 catches the eye under the rear window – a perfect finishing touch for a spectacular bus.