Articulated Bus - Advantages and Disadvantages

Advantages and Disadvantages

The main benefits of an articulated bus over the double-decker bus are rapid simultaneous boarding and disembarkation through more and larger doors, much larger passenger capacity (120+ versus 80−90), increased stability arising from a lower centre of gravity, smaller frontal area gives less air resistance than double decker buses thus better fuel efficiency, often a smaller turning radius, higher maximum service speed, and improved accessibility for people with disabilities and the elderly.

One disadvantage that is sometimes experienced with some articulated models is the insufficiency of the effective motive power available to them. It is common for articulated buses to use the same engine type as non-articulated buses (for example, the Hungarian Ikarus 260 solo and IK 280 bendy share a common 10,350 cubic centimetres (631.6 cu in), 192 brake horsepower (143 kW; 195 PS) inline six diesel engine). The extra weight of the bendy bus gives rise to a slower speed and acceleration. When used in cities built on numerous inclines (e.g. Vancouver, B.C. or San Francisco, California) the vehicle is prone to overheating. This may lead to stalling, or in the worst situations to a full-fledged fire if the bus is powered by a diesel engine. During late 2003 and early 2004, a series of onboard fires on newly delivered Mercedes-Benz Citaros led to Londoners humorously nicknaming the vehicles chariots of fire. Mercedes-Benz quickly addressed the problem, although the vehicles were out of service for a period. However, no overheating or fire-related incidents have ever been recorded in Vancouver's articulated electric trolley buses from a similar cause. Vancouver's articulated trolley buses were specifically chosen for the higher torque output of their electric motors, which typically outperform diesel-based low-floor buses.

In some circumstances of urban operation (such as in areas with high pedestrian volumes, narrow streets and tight turns), articulated buses may also be involved in significantly more accidents than conventional buses. Estimates for London's articulated buses put their involvement in accidents involving pedestrians at over five times the rate of all other buses, and over twice as high for accidents involving cyclists. In a period when articulated buses made up approximately 5% of the London bus fleet, they were involved in 20% of all bus-related deaths, statistics which eventually led to their replacement. However, these safety statistics may be partly skewed due to the buses having been used on the busiest routes in the most crowded areas of the city, making them look worse than the buses they were being compared with.