The longest Mercedes

FRANK BEETON reports on the longest complete Mercedes-Benz bus of all.

Daimler Buses says that transport operators in world cities are experiencing an increase in passenger numbers, but that merely adding to the frequency of services will not provide the optimal solution to this growing demand. This is because of increased congestion that will be caused at bus stops and intersections.

This has prompted the manufacturer to develop a larger 21-m version of the highly successful 19,5-m, Euro-5, Mercedes-Benz CapaCity articulated bus, to accommodate 191 passengers. This vehicle, like its predecessor, will require special exemption from the 18,75-m overall length limit permitted by the German traffic authorities. It complies in all other respects with the dimensional and mass regulations currently in force in that country.

Evolving the new, longer CapaCity L, out of the base Citaro G model, was achieved by the insertion of an additional segment immediately behind the rear axle of the front section, and a forward extension of the rear section immediately behind the articulation joint.

It also required the incorporation of a new, independently suspended electro-hydraulic fourth steering axle under the rear section, which enabled an increase in the permissible gross vehicle mass (GVM) from 28 to 32 t. The result, according to the manufacturer, is the longest complete Mercedes-Benz of all, and the longest regular-service urban European bus combination with one articulated turntable.

The CapaCity L has a turning circle of 24,47 m, and incorporates Mercedes-Benz’s new Articulated Turntable Controller (ATC). This provides hydraulic damping of the turntable to control any potential see-sawing of the rear section when operating on slippery roads – and diminish the chances of jackknifing. There is also a function to limit the swing out of the rear section over the pavement when leaving a bus stop.

Mercedes-Benz claims that the innovations applied to the ATC and linked steered fourth axle, have resulted in an articulated bus that does not handle significantly differently from its smaller brethren.

This new vehicle has its design roots in the modular system of the standard
18,1-m, 163-passenger Mercedes-Benz Citaro G articulated bus. It is powered by the Euro-6, 10,7-litre, OM 470 six-cylinder, in-line diesel engine, which is available with outputs of 265 kW (360 hp) or 290 kW (394 hp).

The engine is mounted longitudinally at the extreme rear of the second section, and drives forward to the third axle through a choice of ZF Ecolife or Voith Diwa torque converter automatic transmissions.

Two cameras provide the driver with an exterior view of the rear section, and the interior layout can be adapted to customer requirements. The option of a fifth access door has also been added to the three or four double-width doors previously provided, to improve the flow of the increased number of passengers. The entire combination is configured with a low floor, providing standing height clearance of 2,3 m.

In the interests of passenger comfort, the vehicle is equipped with electric side-wall radiators and a high-performance auxiliary heating system, as well as top-suspended windows, air ducts with ventilation openings, electrically operated roof hatches and roof fans. There is an optional air-conditioning system with integrated roof heater.

The CapaCity L is set to undergo a customer trial with Hamburger Hochbahn during 2015, configured to accommodate 165 passengers, split between 43 seated and 122 standing.