Premiere: customer takes delivery of first Mercedes-Benz Citaro Low Entry model
Growth in the Citaro family
In addition to the Euro VI variant of the Citaro LE, the short variants of the Citaro, namely the Citaro K, and also right-hand drive Citaro models in the guise of the Citaro Solo and Citaro K, are now also available with Euro VI engines. As a result the urban bus family is almost complete, comprising suitable vehicles to meet virtually every possible customer requirement.
Low Entry: passenger-friendly and economical
As the term "Low Entry" suggests, these buses feature a low-floor design from the front section up to and including the centre entrance, and a raised floor behind the centre entrance (door 2). As well as providing a high level of passenger comfort, even for passengers with restricted mobility, this "composite" design also allows the uncomplicated and maintenance-friendly installation of the major assemblies in the rear area.
Tried-and-tested components from low-floor and raised-floor buses
Like its predecessor, the Citaro LE with Euro VI engine combines the advantages of a low-floor bus with those of a raised-floor bus. Both regular-service buses – the Citaro LE and the Citaro – are practically identical up to the area behind the centre entrance door. The low-floor area of the Citaro LE is exactly the same as that of the Citaro rigid bus. At the same time, in the rear section of the passenger compartment, passengers benefit from enhanced ride comfort thanks to the drive axle and transmission being lifted from the rural-service bus and touring coach modular systems. The raised roof also allows standing room at the rear of the Citaro LE. However, the Citaro LE has only been raised where necessary: as the bus features the same front body section as the standard Citaro, the sense of spaciousness is as pleasant and harmonious at the front as it is at the rear. At the same time the Citaro manages to maintain completely its sleek, distinctive exterior lines.
The look of the Citaro LE
Unlike its predecessor, whose side line rose in the rear area, the new Citaro LE is barely distinguishable from the Citaro solo bus. When viewed from the side, the fact that the floor has been raised by 310 mm from the centre of the vehicle is only noticeable as a result of the slightly longer raised roof section extending towards the front. By adopting the front section of the Citaro and not increasing the height in this area, the bus achieves a well-proportioned overall look. The side line has been retained in full. The optionally available roof-mounted air-conditioning system can be fitted in its familiar place, as on the Citaro. Appearance-wise, passengers will scarcely notice any external difference between the Citaro and the Citaro LE. Even the rear is derived from the solo bus. Only the cooling ribs positioned on the right-hand side of the tailgate, and the raised roof transition, are indicative of the LE variant.
A true Citaro - on the inside too
Links with the Citaro family are clearly evident in the passenger area of the Citaro LE, which includes wall-mounted cantilever seats for the urban bus as well as twin seats with aisle-side supporting feet and the classic handrails which curve outwards at the top. The raised ceiling in the rear area exactly reflects the design of the front ceiling area. The cross duct in the transition from the low-floor front section to the raised rear section conveniently accommodates a destination display or a monitor for the rear rows of seats.
While the Citaro LE makes use of the tried-and-tested City Star Eco seating, the rural-service variant of the Citaro LE comes fitted with Inter Star Eco inter-city seats. In the rural-service version, spacious, trough-shaped luggage racks can be fitted from the front end through to the area above the rear axle. The luggage racks also feature grab rails for the benefit of standing passengers. As an option for rural-service applications, service units comprising ventilation nozzles, reading lights and buttons for the passenger stop request system can be integrated into the luggage racks.
As in the previous model, two shallow steps in front of the rear axle, each 195 mm high, lead up to the raised-floor area at the rear. Thanks to the roof being raised by 310 mm here, the feeling of spaciousness at the rear is as pleasant as at the front of the bus. The floor-to-ceiling height in front of the rear platform is a spacious 2.05 m. The raised floor part rises only gently from the second door, and does away completely with steps. This benefits passive safety and makes it easier to clean the vehicle. All the seats in the rear of the bus face forwards, while the rows rise steadily from front to rear like cinema seats. The rear seat bench has sufficient space to accommodate five passengers.
RO 440 rear axle for coach-like ride comfort
Due to the raised floor concept at the rear, the bus is fitted with the RO 440 hypoid axle, a tried-and-tested performer from the Mercedes-Benz touring coach range. The main advantage of the hypoid axle over the portal axle fitted on vehicles with a low floor throughout is the single-stage ratio of the centrally positioned differential, meaning low inner frictional resistance and, as a result, favourable fuel consumption figures and low noise levels. Since there is more installation space available for the rear axle below the raised floor area, an extremely effective suspension system offering coach-like ride comfort can be fitted. The maximum spring travel of the RO 440 axle has increased by 70 percent compared with a portal axle - that corresponds to an increase in travel of 50 mm, from 70 mm to 120 mm.
Powerful Euro VI engines with Power Boost option
The Citaro LE already makes use of the comprehensively revised and extremely economical Euro VI engine series from the Mercedes-Benz Citaro. Forming the basis of the engine line-up is the vertically installed OM 936 six-cylinder in-line engine with a displacement of 7.7 litres. As standard the engine meets the Euro VI emissions standard, and in the recent Record Run Buses 2012 demonstrated the potential to achieve fuel savings of up to 8.5 percent compared with a Euro V engine. The basic engine has an output of 220 kW (295 hp). As an option, a 260 kW (354 hp) variant is also available. The OM 936 works with two asymmetrical exhaust gas turbochargers and two-stage charging, which helps to guarantee a response which is characterised by high levels of torque.
Even better response is promised by the new Power Boost System (PBS). In brief, this technical refinement will be available for the engine rated at 260 kW. The new system is designed to guarantee better "sprint performance" when moving off, particularly on topographically demanding routes. To achieve this, the Power Boost System pumps compressed air from the standard compressed-air system into the engine's intake tract, thereby increasing air throughput in the short term. This in turn results in increased short-term starting torque, which can prove invaluable at bus stops located on inclines.
Like its urban bus counterpart, gear changes are taken care of in the Citaro LE by an automatic transmission, optionally available from ZF or Voith.
The variants of the new Citaro LE
The Citaro LE range comprises two-axle urban and rural regular-service buses. The Citaro LE urban bus is 12 metres long and comes with a choice of two or three doors. The rural-service bus variant in the guise of the Citaro LE Ü (12 metres long) has two entrance doors, while the Citaro LE MÜ (13.1 metres long) is available both with two and three entrance doors. All variants of the Citaro LE are 2.55 metres wide and have a maximum height of 3.315 m at the rear. The Citaro LE urban regular-service bus can carry 101 passengers, while the rural-service bus has a capacity of 83 passengers (plus the driver's seat in each case).
The handover vehicle in detail
In addition to their economical Euro VI engines, the two Citaro LE buses handed over to infra fürth verkehr gmbh also boast a comprehensive package of equipment and appointments. The 50 City Star passenger seats are supplemented with a wheelchair space with grab handle, stop request buttons and a lean-on area with integrated folding seat (mother/child seat), as well as two additional folding seats in the standing platform area opposite door 2. The interior bus-stop name displays consist of two 48 cm (19-inch) TFT monitors in the front and rear of the vehicle. Linked to an integrated on-board information system (IBIS), they are able to display information on the vehicle's progress along the route as well as the next stop. In addition, news items, event notices and advertisements can also be displayed.
In addition to a video monitoring system for door 2, infra fürth has also ordered a reversing camera which can be used not only as a parking aid but also to monitor the area around the rear of the vehicle. The images are transferred to a video monitor in the driver's cockpit. Additional safety equipment includes a fire alarm and extinguishing system in the engine compartment.
About infra fürth verkehr gmbh
The company infra fürth verkehr gmbh is responsible for the entire public local transport system in the city of Fürth. With 8 routes covering a route length of around 1147 kilometres, the transport operator carried around 18 million passengers in 2012. The company's fleet currently comprises 54 vehicles, 48 of which are Citaro models. Among these 48 vehicles is also the milestone 25,000th Citaro, which was handed over to infra fürth verkehr gmbh in a special ceremony in Stuttgart in 2009. The two Citaro LE vehicles with Euro VI engines will be deployed in future on all routes in the Franconian city of Fürth.
Credits: Daimler AG
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