Like most fields, public transportation is swollen with studies, both in the U.S. and abroad. Yet some of the most fascinating things seem to be never studied, or rarely studied.
One example of this phenomenon comes from my experience examining more than 80 incidents involving vehicle-pedestrian and vehicle-vehicle incidents. Many of them involved buses or coaches turning. I learned many unique things from these incidents. Yet some things are still puzzling. One of them is the dozens of incidents that involved buses, motorcoaches or van- and minibus-conversions (to accessible vehicles) making left turns. Yet I cannot recall a single incident involving a right turn.
The Danger Deterrent
Residing in Los Angeles County from 1980 to 1997, I recall a famous and seemingly-treacherous, un-signalized traffic circle in Beverly Hills. This circle contained three through-streets, or six "spokes:" North Canon Drive, North Beverly Driver and Lomites Avenue -- one spoke of which lay almost precisely 60 degrees around the circle from the next. At the point where it faced the circle, each street ended with a mere stop sign -- while the risk entering this circle seemed to cry out for yellow-and-purple-striped nuclear warning danger tape. While North Canon was more of a "collector" street than its counterparts, this notion was barely distinguishable to a motorist who neither lived near nor regularly drove through this circle. As a consequence, there were absolutely no clues about which corner's approaching traffic had the right-of-way.
To a seasoned traffic engineer or transportation planner, a Google-Earth view of this intersection is breathtaking. In the Google-Earth view, the two vehicles shown appear ready to crash into one another. Other than the travel speeds of its cross-streets, this intersection is more intimidating than a Figure 8 racetrack. Reflecting this risk, when first coming upon it, and on every successive occasion, I came to a complete stop. And motorists entering the circle from almost every street hand-signaled one another to either enter first, or to offer thanks for allowing them to. Most of us verily crept across the circle, glancing at the other five spokes and traffic flow within the intersection continuously. Defensive driving on steroids.
I learned what was so astonishing about this traffic circle in 1983, while preparing the City of Beverly Hills' first transportation plan. What was so extraordinary was that, up until that time, there was not a single accident at this intersection on record. Yet no one in the City's traffic department had any understanding why. Like myself, several speculated that it was simply because the intersection appeared so profoundly dangerous upon approach that even a compromised motorist (like a drunk driver) would be hesitant to do anything but inch across it -- already "reacting," and ready to brake at any moment.
In between visibly-threatening hazards and risks difficult to see (e.g., black ice) lies a spectrum of risks that bus drivers would do well to be trained to recognize and properly mitigate. One of them is a left turn.
Right to Left Turn Ratios
As I noted above, I have been involved as an expert witness in several dozen left-turn accidents while none involving right turns. One fellow-expert I know has done six cases involving right turns, and feels that there are "many more out there." Yet, like me, he does not recall ever reviewing an intelligible study about them. I have seen turning addressed in professional drivers' manuals. But the information and insights were marginal. I do not recall ever seeing anything in these sections about reaction and braking distance -- which would typically cover much more distance than for a right turn.
Thinking about this phenomenon a bit more, left turns for vehicles with large wheelbases would seem almost exponentially easier than right turns. Compared to right turns, most left turns are almost sweeping. While "rocking and rolling" should effectively eliminate otherwise blind spots in either, visibility in left turns is still easier: Most of the time, objects with which the bus might collide lie almost directly in front of it.
Another oddity it that right turns into narrow cross-streets require even more of the bus to enter the perpendicular roadway's oncoming lanes -- usually for several seconds. Professional drivers are taught to "rock-and-roll" through all types of turns. But the increased "otherwise-blind-spots" of a right turn are further marginalized by the vehicle's lower deceleration and acceleration through the turn. Still, given the dimensions and geometry of most right turns, right turns would seem to intensify one's need to rock-and-roll. However, visibility for right turns is largely through mirrors, doors and side-windows. For left turns, visibility is mostly through the windshield.
A final distinction is that, in making a right turn, the bus driver need worry only about (a) vehicles approaching from the left after passing through a red or amber light, (b) oncoming vehicles turning left, and (c) vehicles too close to the limit line in the oncoming lanes of the right turn. In contrast, a left-turning vehicle has to worry about (a) vehicles coming from the right (against the light), (b) vehicles turning left from the oncoming lane of the cross-street (again, against the light) and (c) vehicles in the oncoming lane traveling straight through the intersection -- on the same green light the bus driver has. If left turns are beginning to sound complex and challenging, this is because they are.
Safety and Liability
Despite the size of a bus and the dimensions and geometry of most intersections, the comparative safety of making both types of turns, with a bus, should not be dramatically different. Yet from my forensic experiences, left turns cause exponentially more carnage. Regardless, professional drivers of "common carriers" are held to the highest standard and duty of care. When jurors view the video of a pedestrian waltzing across a bus' windshield moments before being mowed down, the highest standard and duty of care is the last thing that comes to mind.
Operating below this standard of care is not necessarily endemic to every bus-turn-related collision, even while, in most municipalities, pedestrians have the "right of way." Of course, in five States (Virginia, Maryland, Delaware, North Carolina and Alabama), this concept is only an illusion. In those States, if the victim is even one percent at fault, the parties overwhelmingly at fault "walk away" from the inevitable lawsuit. But not always. I recently helped one of these victims recover $4.5M in one of these States.
A vehicle or pedestrian who darts into the roadway only seconds before a bus gets there would also seem to be at fault. But this would not be so if the darter or his/her vehicle -- poised to dart -- was in full view of the professional driver for hundreds of feet before the collision -- or should have been. Again, this reality reflects a pedestrian or motorist's ordinary duty of care in contrast to a professional driver's highest duty of care. Further, a bus driver is taught and certified in defensive driving -- as a necessary requirement for obtaining a commercial driver's license. A pedestrian or common motorist is taught virtually, although some motorists have at least learned a few dollops from "Driver's Ed."
Regarding right- versus left-turn collisions, one factor that might help explain the predominance of left-turn incidents is the fact that the most segments of a buses movement through a left turn is significantly faster. This translates into a problem because of reaction time-and-distance and braking distance. If the driver of a full-size bus or coach with pneumatic brakes begins the turn at 20 mph (which one would almost never do for a right turn), the vehicle will travel almost 59 feet during the driver's reaction time alone. Then it would take roughly another 32 feet for this vehicle to stop (slightly less if it were lightly-loaded). In simple terms, beginning the turn at this speed, a driver would have to spot an object in front of it more than 90 feet away to avoid striking it.
Given these figures, it would seem like a terrific idea to pull the bus or coach to a complete stop before making a left turn. This is actually the policy of some transit agencies, and regulatory reality in at least one State I know of. Otherwise, in many of the left-turn-related bus-pedestrian collisions I have examined as a forensic expert, the drivers claimed to have seen no one in front of their vehicles until they struck the pedestrian. This lapse may work well in a cartoon. But it does not play well to jurors, who usually perceive the driver as a liar.
Another oddity about turns is related to a bus or coach's long wheelbase. If the turn is properly made -- not turning until the rear axle is aligned with the extended near-side curb line -- many buses or coaches would crash through the front window of a building on the far-side corner. In one left turning case I did years ago, a schoolbus driver trying to avoid this fate at an intersection hopelessly too small to accommodate the vehicle turned so prematurely that its rear tires ran over the town drunk literally standing on the sidewalk on the near-side corner. So the dimensions of the bus or coach compared to those of the intersection provide another important reason why it would make sense for a bus driver to come to a complete stop before initiating a turn -- and before doing so, to also take a good look around, and perhaps a deep breath.
Some of these problems might be solved by improving or expanding the intersection. Others could be mitigated by routes designed to avoid them. I would not bet on the former happening in a country with 70,000 bridges in need of repair. And I would not bet on the latter where many routes -- particularly in schoolbus and transit service -- are determined by scheduling software, where live Earthlings have never examined the intersection, and/or where drivers are too complacent or powerless to complain about it.
Always Expect the Expected
The cardinal principle of defensive driving is "Always Expect the Unexpected." Yet a pedestrian ambling through a crosswalk is hardly unexpected. Nor is a motorcycle or car approaching, and close to, an intersection where a bus turns left in front of it. Perhaps the Smith System should be amended to include "Expect the Obvious." Because in a courtroom, the employer (and/or its insurance carrier) of a driver who does not do this is likely to pay dearly for it. Particularly when the object struck is captured on a video, the obvious is even more exaggerated. Jurors have to wonder where the bus driver's mind was while the turn was occurring -- if, again, they do not conclude that he or she is simply lying. In three recent cases in which I was involved as an expert, the pedestrian was more than half-way across the crosswalk before being struck. In one case, the driver claimed he did not even notice that the pedestrian's head made a four-foot-long crack in the windshield right in front of the driver's eyeballs.
The worst part of all this is obviously that some innocent person was killed or maimed. Otherwise, driver error is only the beginning of what seems to many as a witch hunt for management culprits. Other factors often examined include how and what the drivers were trained, how their performance was evaluated, what their employer's policies were, and whether the route's schedule was too tight -- among many other aspects of policy-making, planning and management. A savvy attorney and knowledgeable expert will scrutinize every nook and cranny of this employer's management structure, and its performance. So when a driver makes a simple and seemingly-inexcusable error, his or her employer is likely to be toasted.
Given the magnitude of left-turn killing and mutilation involving buses, it may be time to bring back the old classic, "See Spot Run," and re-learn the basic idea of "Stop, look and listen!" Drivers who regularly do this usually discover objects they might otherwise strike in time to avoid hitting them. Equally important is it to pay even more attention to those situations that appear to present obvious risks. There is certainly a big difference between Chicago and Cheyenne. But in most places, left turns should be a recognizable hazard all by themselves. Not treating them as such will admittedly ease the challenges of a tight schedule. But not treating them as hazards also compounds the risk.
As a final thought, monitoring is the Achilles heel of public transportation -- certainly in this country, and likely in many or most others. This vacuum leaves drivers marginally- or un-supervised. So one approach to at least reduce the number of these accidents it to grant drivers some input into the route-design process, encourage their feedback about hazardous conditions, and teach them that many left turns are just that. In the current operating environment, drivers seem stuck with the route and its schedule. Perhaps it is a time to lean on those individuals with the most experience actually making turns. Of course, paying them better would not hurt either. But that is a much larger problem that cannot be addressed from within our industry.