Safety Compromises Part 9: Rolling Turns and Sharp Turns

It might seem obvious that a bus driver would know how to properly turn a vehicle with a long wheelbase. Yet it is surprising how many are not taught to. More interesting, bus drivers often do not have the time to.

In some states, municipalities (e.g., Louisville) and/or transit agencies, bus drivers are required to come to a complete stop before turning left. But with the tight schedules common to most routes of many transit systems, coming to a complete stop before every left turn could consume a considerable amount of running time. This is especially true if the driver gets caught in the light during a few stops. But even without getting caught in the light, coming to a stop or a crawl before turning left can consume 15 or 20 seconds per intersection. Fifteen or 20 seconds more than a rolling turn would consume.

Right turns are not nearly as problematic (see “Dancing in the Oncoming Lane” in NATIONAL BUS TRADER, August, 2016). This is less true where the intersecting street is very wide. Otherwise, the bus will spend a few seconds in the oncoming lane before returning to its appropriate travel lane after the turn. This problem is made worse by a nation full of signalized intersections with limit lines needlessly too close to the intersections – often more than a bus-length too close. Also, a bus driver cannot make a right turn at a high speed: If he or she did, the bus could roll over. Keeping the speed down eliminates this risk. Otherwise, rocking-and-rolling before and through the turn is even more essential for making right turns – which might otherwise contain some blind spots.

In contrast, with the sweeping arcs of many left turns, drivers can race through them at much higher speeds. Such turns would shave time off their already-too-tight schedules. This practice certainly reduces the risks of getting caught in the light. But in addition to mowing down pedestrians, drivers doing this can also prematurely cut in front of oncoming through-traffic too close to the turning bus to stop before driving into or through it (see “The Danger Deterrent,” in NATIONAL BUS TRADER, April, 2016).

The Proof and the Pudding

The correlation of insufficient running time with tight schedules is not an un-researched hunch: I have been testifying about this correlation for more than a decade now. More significantly, in 2014, Seattle METRO conducted a study in response to a plethora of high-profile accidents where drivers mowed down pedestrians in crosswalks during left turns. (See article in sidebar.) Seattle METRO found a  stunning correlation between insufficient running time and left turn accidents, although METRO blamed some of the collisions on “blind spots.” As every professional driver knows, or should know, “rocking-and-rolling” in the driver’s seat almost always eliminates what would otherwise be a blind spot. Regardless the proof of this correlation between insufficient running time and left turn collisions exists.

The pudding is what a transit agency or other defendant becomes when some expert witness who understands this rides and times the route to find recovery time non-existent. This is even more problematic when that route’s drivers rarely let a boarding passenger reach a seat or stanchion before zooming away – and the schedule is still so tight that no recovery time still exists – apart from that which the driver can create through the commission of still other safety compromises (see

Rolling Turns and Arithmetic

Coming to a complete stop, a driver has a much better chance of looking around – mostly to gauge the distance in front of the bus from oncoming cars, and to look for pedestrians in or approaching the crosswalk. In contrast, when turning at a constant speed (which drivers should not do anyway) at 20 mph, the bus covers roughly 59 feet during a typical driver’s reaction time. And then it takes roughly another 32 feet to brake to a stop. Most drivers who mow down pedestrians testify that, “I never saw him [or her]. He [or she] came from out of nowhere.” Yet they manage to stop their vehicles a few feet from the collision. Doing the arithmetic, it is always clear what the driver did: He or she saw the pedestrian in the crosswalk long before striking him or her. But in a rolling turn at 20 mph., or even 10 mph, the driver was not able to stop before striking the pedestrian. And while an expert witness for the plaintiff surely helps to analyze and testify crossing or turning accidents (see and, he or she need not be a reconstructionist. The arithmetic needed was learned in the third grade (multiplication), fourth grade (long division) and usually 11th-grade (drivers’ education). In drivers’ education, one employs third and fourth grade math to learn about reaction time and braking distance.

Another problem with rolling left turns is wheelchair securement. This feat of kindergarten skill is either rarely done or partially done (i.e. securing only the aisle sides of the chair) by transit drivers. It is rarely done by NEMT drivers (largely because the service providers earn no money when the vehicle is not moving). Paratransit drivers often do not as well, because their schedules are hopelessly too tight (largely because they were made by scheduling software). So few wheelchair users ride motorcoaches that their drivers often have no clue about how to secure a chair. When they do – after spending 10 to 15 minutes relocating passengers, flipping up seats, and operating the wheelchair lift – they often do not bother to secure the chair because, at that point, they are hopelessly behind schedule.

Finally, rolling turns can pitch passengers out of aisle seats onto the floor, or pitch those in wallside seats against the windows. In my weekly commuter/express ride to my country office, the schedules are so tight that the drivers speed around winding mountain roads so fast that passengers often bump into those seated beside them. On many occasions I have been tossed into the aisle. I suppose this occurrence is the real reason that the aisle-side seatbacks are outfitted with grab handles. Experienced cowboys accustomed to riding bucking broncos are more adept at holding on. And they are more adept at remaining in their seats even when they do not hold on. In contrast, most urban dwellers are no match for a commuter/express coach racing around winding roads on a tight schedule.

Forces and Folly

I have written often about how centrifugal and inertial centrifugal forces can affect passengers (see “The Mysterious Force,” NATIONAL BUS TRADER, December, 2001). We often learn of these forces in 7th grade science class, when the teacher swings a pail of water around his or her head and nothing flows out. Yet the mention of these forces is rare in driver training materials for every mode of public transportation. It is folly to not teach or remind drivers (rarely science teachers) about such things.

As noted, a sharp right turn for a bus in most intersections is impossible. But an alert turn is always possible. And always necessary. This is also true for left turns, even while racing through them is enticing.

When centrifugal or inertial forces are unleashed on passengers, the agency or company is fodder in a keenly-focused law suit. When the schedule was too tight, and it is shown that these forces were the result of a schedule being too tight, the case nears the magic word that plaintiffs’ attorneys love to here: ‘Deliberate.’ This is because ‘deliberate’ – commonly referred to as “willful and wanton” – may translate into a judge instructing the jury that it can assess punitive damages. In really ugly incidents where some expert demonstrates that the incident was a deliberate trade-off for something else (see, jurors can be outraged. Assessing punitive damages is simply a means of venting this rage.

Clash, Crash, Splash and Cash

Try this tongue-twister out loud – quickly – even once. Just wait until transit agencies begin deploying autonomous buses programmed to turn safely. Just wait until someone like myself finds their robots reprogrammed to accommodate an agency’s safety compromises. This ploy may seem like a transit agency’s escape from accountability. After all, would a bus manufacturer “give up” a major customer to defend itself in the inevitable lawsuit when it was asked by that customer to re-program its robots to race through rolling turns?

In this future, values will crash as they clash with cash. This collision should produce quite a splash. But values and cash have been colliding for quite some time now, often in public transportation. Just wait until some robots come along designed to operate safely. Re-programming them to make safety compromises will make quite a splash when some journalist figures it out. Woe be the first transit agency identified as the culprit.

Check out Turning Accidents — An Expert Witness Take

Publications: Articles about Safety Compromises.