The U.S. transit industry has essentially converted to low-floor transit buses for most new orders. Much of the rationale for choosing these designs is based on two primary arguments: customer convenience and more cost-effective compliance with accessibility regulations.
As was the case first in Europe, and later in many cities worldwide, low-floor transit buses have virtually completed their conquest of the North American marketplace. Indeed, no manufacturer now offers a standard-floor vehicle (i.e., a higher floor with steps at the doors). Low-floor design advantages include faster boarding and alighting for the majority of passengers, as well as elimination of the traditional wheelchair lift, which has been one of the biggest sources of maintenance-related road calls since accessible buses began to be mandated in the U.S.
However, there are applications where these benefits may be trumped by those of standard-floor buses, including the accommodation of the preference of many riders who would rather sit higher above the roadway, as well as higher capacity in vehicles of comparable size.
To bus engineers, every design decision represents a trade-off, with advantages in certain areas inevitably creating disadvantages in others, and the choice of floor design is no exception. Given the growing, near universal enthusiasm over low-floor buses among today’s public transit fleets, could some of their disadvantages be overlooked?
Standard-floor designs may be worth another look for two considerations, the first of which is that many passengers prefer a higher seated position. This is particularly true of passengers on higher-speed commuter routes. Several bus manufacturer executives have noted that the first areas of a stepped low-floor bus to fill up with passengers tends to be the higher-floor sections. Whether it is a perceived safety consideration or preference for looking out the windows at a higher level, many passengers do prefer seating in those sections — even if they prefer the lower floor at entry and exit.
This is particularly true at higher speeds. They report that in express routes, for example, riding in the lower floor section at higher speeds feels to some customers like “riding in a bathtub.” Perhaps this explains why many people prefer SUVs and trucks over regular passenger car designs, capacity issues aside.
It is also important to note that wheelchair lifts have substantially improved in reliability during the past two decades. The present generation of wheelchair lifts, now in wide use on paratransit and other fleets, are far more reliable.
Further, in some applications, longer dwell times may not be as important to fleet productivity or customer convenience as the rest of regular-route transit service. One such example is commuter or express service. The additional dwell time needed for wheelchair lift deployment to assist boarding and alighting of mobility-impaired patrons is not as important an issue in these applications as comfort, speed and capacity.
Moreover, wheelchair ramps are still designed with actuator, linkages, safety gates and other components. Although certainly less complex overall than a conventional lift, these ramps also present maintenance challenges — they require the drivers to leave their seats to deploy the ramps and assist passengers with their securement systems. Thus it is not clear how much dwell time or maintenance-related savings are being achieved.
Operating cost advantages?
The second reason why transit agencies may want to reconsider using low-floor buses in all applications in their service areas is the inherent disadvantage in low-floor buses of standard floor design with fewer seats per coach. This could help explain some rising operating costs in recent years.
According to National Transit Database (www.ntdprogram.gov) statistics, per-passenger operating costs have actually risen in recent years, from $2.15 in 1995 — when low-floor buses really began to be delivered to agencies in large volumes — to $2.54 in 2002, the most recent year studied. This represents a rise of 18 percent, at a time when the average fleet age was actually decreasing, due to record levels of funding that allowed transit agencies to replace their aging vehicles. It was also at a time when ridership continued to climb at levels not seen since the 1950s. Could low-floor buses be part of the reason?
There could be a number of explanations for rising operating costs, including higher driver and maintenance technician wages, additional high-tech equipment, poorer fuel economy of alternative fuels and costs associated with more stringent emission controls, among other factors.
These rising costs, however, could be exacerbated by the trend toward low-floor bus procurements for the following reasons: