Fatal Rear-End Impact of Mississauga Transit Bus – Issues Need Explanation
Informing the public about deadly dangers must be an unquestioned responsibility of those who have exclusive information about those dangers. That responsibility was needed in the latest fatal collision on Derry Road in Mississauga, Ontario when a passenger car rear-ended a stopped transit bus. Even though another fatal collision could occur because nothing will be changed, police and news media failed to inform the public of the deadly danger that may have been a factor in the death of a male driver of the car. Clearly an immediate concern had to revolve around the visibility of the transit bus that was stopped at a bus stop in a live lane that had a posted maximum speed of 70 km/h. Anyone who has performed traffic studies (such as those performed by Gorski Consulting) would recognize that about 20 per cent of drivers could be travelling at or above 90 km/h in a zone posted with a maximum speed of 70 km/h. Therefore was it safe to place a bus stop in such a live lane?
There has been no information provided about what conditions existed at the time of collision except that the road surface was dry. What levels of artificial illumination were available in the vicinity of the stopped bus remains unknown.
A photo provided by the CBC showed the bus and striking vehicle at their final rest positions. This photo showed that the bus did not have its emergency flashing lights activated at the time that the photo was taken. Was this just coincidence such that someone turned them off after the collision? Or did the bus not have its lights activated at time time of the crash? For news reporters who interview police that would have been an important question to ask. However police policy in every known jurisdiction has now created “spokespersons” – persons who are trained to give no details and to answer questions in a roundabout way while concealing information that, ethically, the public has a right to know. So, if a police spokesperson were asked whether there is a present danger that another transit bus could be rear-ended in night-time conditions would he or she reply that the concern exists? Likely not. What is always said is that the investigation is ongoing and that investigators are gathering evidence. Evidence that will rarely be shared with the public whose lives might be threatened.
Up to now there has been no indication from police that the deceased driver was impaired by alcohol or drugs. But even if that were so that does not absolve official agencies from pointing out the danger to anyone whose abilities may not be impaired.
Why this is mentioned is due to previous analysis conducted by Gorski Consulting. For example Gorski Consulting conducted an analysis of a similar incident, not too far from the present site, where a serious, rear-end impact occurred due to a visibility obstruction caused by the presence of heavy trucks. In short, due to the length, width and height of heavy trucks they create large barriers and when two or three of these trucks are travelling close behind each other, like they often do, they create a wall that obstructs visibility ahead for a substantial distance. This is particularly crucial on major arterials such as Derry Road where there are 3 travel lanes. Videotaped observations of traffic on such roads by Gorski Consulting has shown that lane changes are very common and those lane changes do not always occur toward the left, but lane changes toward the right are just as common. What this means is that when slow-moving, heavy trucks move into a left or middle lane, drivers following behind will move into the right lane to pass the slower vehicles without being able to see if that right lane is blocked. This is precisely the kind of condition that could have occurred at the site of the present fatal collision – regardless of driver impairment. Even if the bus had its emergency lights (“flashers”) activated a driver, sitting on the left side of a car’s interior, would not be able to see the road ahead, past the rear end of a truck trailer, in sufficient time to avoid a collision at the heightened speeds involved.
Yet municipal staff create such dangerous scenarios with respect to bus stops without being made accountable for their actions. Just before I resigned my position on the City of London Transportation Advisory Committee I was in attendance when City Staff gave a presentation about proposed widening of an arterial road on which transit buses would be travelling. One of the problems I observed was that there were no plans for the installation of bus bays that would allow buses to be steered out of the curb lane and therefore allow traffic to pass the bus without changing lanes. I asked the city presenter this simple question: “Do I understand correctly that you are not intending to provide a bus bay at this location and that the bus will stop within the curb lane?” The answer was given in the affirmation without further explanation. It was only several minutes later, when another staffer recognized the concerned looks of other advisory committee members, that this staffer explained that the reason why bus bays were no longer being recommended in London is because, through a discussion with representatives of the London Transit Commission it was learned that bus drivers were having difficulty re-entering a curb lane and this delay was affecting their schedules. Yet the delay to transit buses should not be the only factor in this decision. Clearly vehicles attempting to pass a stopped transit bus will change lanes and often there are conflicts as many more vehicles end up making lane changes and this causes a potential for collisions. But because those collisions can be blamed on the erroneous decisions of private citizens it becomes of no importance to city staffers because the City will not be held responsible for those collisions. And so these are the kinds of problems that are enabled when there is no oversight into actions and decisions of city staff.
…and there are other issues.
Airbags, like seatbelts, have been shown to provide tremendous benefit to our society and this is why Gorski Consulting has continued to support their installation. But when problems are detected that expose the public to needless danger those problems need to be publicly exposed so that they are corrected. Despite that the truth may be inconvenient it must be revealed because we value human life more than we fear that inconvenience. Yet there are numerous persons in our society who continue to believe that the “end justifies the means” and therefore any and all means are justified. So problems associated with such life-saving technology such as airbags and seatbelts are justifiably hidden.
In the present case, broad frontal impacts, at 50 km/h (30 mph) into an immovable barrier (transit bus) are precisely the kinds of impacts that have been studied in detail since the 1960s evolution of the U.S. NHTSA and Transport Canada’s Road Safety Branch. Before we recognized that there was a difference between crash tests and real-life collisions we determined that we must manufacture a vehicle where the driver withstands this broad frontal impact. Thus, of all the unique collision scenarios that exist in the real world a driver is most protected in a broad frontal impact into an immovable barrier.
So what happened in our real-life collision? This was as broad and frontal as any crash could be. And, although the crush to the front end of the car was substantial, many controlled tests have demonstrated that, accompanied by airbags and pre-tensioned seat-belts a driver should be able to survive a tremendous change-in-velocity, provided that there is no significant structural intrusion into the occupant space. So again we ask, what happened here? The single photo (even though insufficient) seems to show that there was no meaningful structural intrusion. So why did this 45-year-old male driver die?
Well, unlike controlled crash tests there is a slight but important difference that could be a critical factor but was not mentioned by either the police nor news media. It has to do with the vertical level of crush on the front end of the car and what that does to the timing of deployment of an airbag. Airbags need to be aniticipitory to a large degree because of the need to get them fully inflated before the body of the driver reaches them during the crash. As an example, an unrestrained driver’s body begins to move forward in relation to the vehicle interior commencing at about 60 milli-seconds. There are 1000 milli-seconds in one second. So this is a very short time. Meanwhile an airbag must commence deployment and become fully deployed before the body of the occupant reaches it. So this is a very short time to begin and complete this inflation. And this is why the inflation must be equivalent to an “explosion”. An algorithm within an airbag control module studies the crash pulse which eventually leads to a decision about how airbag deployment takes place. Such algorithms have problems when stiff areas of a vehicle’s front end, such as the bumper, are not the major part of the crushing mechanism. The rear bumper of the bus was high enough that the front bumper of the car was not fully engaged in the crush of the vehicle. This is accentuated by maximum braking that drops the vertical height of a car bumper. The crush that takes place above the bumper is to a softer portion of the structure where the rate of change in acceleration (called “jerk”) is not high enough to produce an immediate firing of the airbag. In other words the airbag fires late when the driver’s body has already moved into a position that is too close to the airbag. The driver is then killed, not necessarily or primarily, by the impact force, but by the force exerted by the exploding airbag. This is an unwanted outcome. It is not wanted by manufacturers, government agencies, police, or anyone who might have to do something about the problem. The best that can be done is to hide the problem and that is often what is done. The end justifies the means. If we hide the fact that a problem exists the public will continue to be confident about the safety of airbags and that is the justified end. But is that really the best approach?
So did this unfortunate driver die because of being out of position (OOP) when the airbag deployed. It will never be publicly revealed and therefore actions to improve airbag performance will continue at a slower pace. And here is the problem. When you do not identify a problem for which there is no immediate or simple fix, much like climate change, or other difficult issues, you slow down the timing and efficiency of its correction.
But there are greater problems that are generated when members of the public detect the problems that are being hidden. Once that happens they lose confidence in those agencies who have hidden the problem. When that happens it becomes much harder to correct the problem because no matter what is said it is no longer believed. It is commonly believed that honesty is for fools and losers and our society thrives on manipulation and deceit. What we have lost is the understanding that truth and transparency can be a strategic advantage to our functioning. Being known as an entity that can be relied upon is a powerful possession in the hands of those who work for the public’s interest.
School Bus Collision West of Smoky Lake Alberta Reminiscent of Humboldt Broncos
The site of this school bus crash near Smoky Lake Alberta is similar in many ways to that of the Humboldt Broncos crash.
This view of the Humboldt Broncos bus crash in April, 2018 shows the similarities in the vehicle angles of departure.
A bus crash near Smoky Lake Alberta this week brings back memories of the Humboldt Broncos crash. Looking at the two crash site photos (above) there is an eerie similarity with respect to the final rest positions of the vehicles. In the Smoky Lake case a smaller truck collided with a school carrying 14 students. Critical injuries were reported to some students but little further information has been provided.
A major difference between the Smoky Lake collision and the Humboldt Broncos tragedy is that the school bus was struck in the right side. In contrast the Humboldt Broncos bus struck the side a large, loaded trailer of a Tractor-trailer combination. The side of any vehicle provides less protection to its occupants for obvious reasons as there is less structure available to protect the occupants from the impact force and structural intrusion. Thus, on face value, one should expect that the occupants would be more vulnerable to injury in this school bus than in the Humboldt Broncos crash. Yet, although the severity of injuries has not be fully established, substantially more injury, and death occurred in the Humboldt Broncos crash.
The extent of structural intrusion into the side of the bus, along with the obvious change-in-velocity would make this comparable in severity to the Humboldt Broncos crash, yet there have been no reports of fatalities at this time.
Few have been willing to highlight the obvious fact that very little of substance has been released with respect to how the occupants of the Humboldt Broncos bus sustained their injuries. The RCMP, which was the only official agency allowed on the site, and was the only agency that could document crucial facts about the crash, have never released their report for public evaluation. Without such details there are critical concerns about what has been reported and this can be contrasted with what is visible in the travel paths and rest positions of the vehicles in both collisions.
For example a momentum analysis is frequently used in collision reconstruction to establish the pre-impact speed of vehicles. Such an analysis uses some of the following details taken from the post-impact status of the evidence.
- The pre-impact travel directions of the vehicles.
- The mass of the vehicles
- The post-impact travel angle of the vehicles
- The post-impact travel distance of the vehicles
Using such data a momentum analysis is a “closed box” such that, based on the above assumptions, an exact value of the pre-impact speeds and collision severity will be the resultant output. Opposing analysts argue about the assumptions being placed in this closed box because, once those assumptions are accepted the momentum results are straightforward. However, when the details that are necessary to complete a momentum analysis are not provided, such as the case in the Humboldt Broncos matter, the validity of a momentum analysis, or any analysis of pre-impact speed, can be in dispute. So, without those details, only very broad observations can be made. And when no further information is available the only understanding that can be obtained is through blind faith that those providing the conclusions have, in fact, performed their analysis in a crediable, valid manner.
Here is one of the general observations that can be made from both collision sites. The angle of departure of the vehicles in both crashes is similar. For simplicity, if we assumed that the masses of the vehicles in both crashes were similar in proportion to each other then the only factor that would cause these similar departure angles is the speed of the vehicles coming into impact. We have been told that, in the Broncos crash the loaded truck failed to stop at a stop sign and was reportedly travelling at highway speed at the time of impact. Similarly, the Broncos bus was also travelling at highway speed at the time of impact. Thus we should expect to see a departure angle of both vehicles in the range of about 45 degrees, and this is generally what is shown in the photo of the accident site above.
However the 45 degree angle of departure in the school bus crash at Smoky Lake is also visible in the collision site photo (above). Yet police reported that the school bus driver had stopped at the stop sign and then pulled out before the school bus was struck in its right side. So how could that make sense? If the truck was travelling at highway speed and the angle of departure was about 45 degrees, then the school bus must also have been travelling at highway speed. Yet how could the school bus be travelling at highway speed when it has just pulled out from a stopped position at the stop sign?
One of the ways reconstructionists settle these discrepancies is by also considering the energy that was dissipated in the crash. So if both vehicles are travelling very quickly we should see a lot more crush in the structures of the vehicles than if both vehicles are travelling slowly. Once again, without any details except what we can see in the site photos, this energy analysis must be very broad. It has been observed that a number of persons came to the conclusion that the roof of the Broncos bus was detached as a result of the collision and therefore it should be not surprising that fatalities occurred. However this detachment is very suspicious as there is no explanation why the roof pillars would be “cut” in the manner they appear to be. Conversely it is well known that emergency personnel will cut off a roof, especially when there are many injured occupants. Thus this roof detachment is likely not related to the severity of the collision and is likely a red herring that is confusing the public. The principal crush was at the front end of the Broncos bus and therefore it would be prudent to inquire if any occupants sustained major injuries when they were located a substantial distance, within the bus, from that crush. It is well understood that when a long vehicle is involved, and occupants are located far from the point of crush, the severity of a collision experienced by those distant occupants is different than the severity experienced by the occupants close to the area of crush. It is unlikely that all the fatally injured and critically injured occupants of the Humboldt Broncos bus were located at the very front where all the crush took place. So this issue needs proper study.
Finally, we can look at the travel distances of the vehicles after the impact. In general, when we look at the combined travel distances of both vehicles, the vehicles that are travelling at a faster speed before impact will also travel a longer distance after impact. Yes, that is a very bold simplification because that is not always true, but without the availability of the precise evidence, we can make that broad observation. Looking at the travel distances shown in the two sites, if anything, it would appear as if the two vehicles in the Humboldt Broncos crash travelled a shorter distance than the two vehicles in the Smoky Lake crash. On this basis it should cause us to ponder why this is so. Certainly factors such as rates of post-impact deceleration could be different, or other issues may be at play. But we cannot study this further because the police had not released the evidence to allow a more detailed analysis. All we can say is that something appears to be inconsistent.
After the Humboldt Broncos collision a Canadian Parliamentary Committee was formed to study bus passenger safety. Hearings were held though the spring of 2019 and a number of witnesses attended providing their opinions as to how we can improve passenger safety. At the same time a CBC Fifth Estate documentary was focusing the public’s attention on the lack of seat-belts on school buses. Many differing opinions were expressed. Regrettably, the Parliamentary Committee was disbanded when the federal elections commenced and it is yet to be determined if a new committee will be formed to continue the discussion.
Myself and Professor Ahmed Shalaby, of the University of Manitoba Transportation Department, co-wrote a brief to the Parliamentary Committee with our observations and recommendations. One of those observations was the lack of open, independent investigation that is currently conducted whenever a major bus collision occurs. While police are supposed to be impartial in their investigations, there are practical difficulties that interfere with that impartiality. And, as witnessed in the case of the Humboldt Broncos crash, objective evidence can become hidden from the public’s eye. It was our observation that in the U.S. the independent National Transportation Safety Board (NTSB) is empowered to investigate bus collisions such as the Broncos incident. But that is not so in Canada. In Canada the Transportation Safety Board (TSB) would only become involved in a bus collision if that bus was in collision with another mode of transportation such as a railway train, an airplane or ship. This provides an extreme limit on its ability to document bus safety problems. Thus we recommended that the mandate of the TSB be changed. Ours was the only submission that called for that change.
We see once again that a major bus crash has occurred at Smoky Lake. Although there is no current information that a fatality occurred, the fact that several passengers sustained critical injuries suggests that the possibility of a fatal result is not out of the realm of possibility. Even so, the levels of injury are an important matter that needs detailed and unbiased documentation that is released to the public. Much like the Humboldt Broncos case, it is unlikely that this will happen.
There is an overall lack of transparency with respect to collision data in Canada that was also one of the observations made in the Shalaby & Gorski brief. While various agencies conduct investigations and research studies these are rarely available to independent researchers and to the public in general. If we are to increase our efficiency in studying road safety problems this lack of transparency needs to be addressed.
The Fast and The Furiously Burning
A fatal vehicle fire in Fort Lauderdale Florida is reminiscent of the fire death of Paul Walker from the “Fast & The Furious” But it also illuminates some confusing issues.
This photo was taken shortly after a 2014 Model S Tesla electric-powered sedan went out of control on a curve of Seabreeze Boulevard in Fort Lauderdale and crashed into a roadside wall on May 8, 2018.
Two young men Barrett Riley and Edgar Monserratt died in the crash. A third male occupant, Alexander Berry, was reportedly ejected from the vehicle and survived. A lawsuit, filed on October 8, 2019, by Riley’s father claimed that his son did not die from the collision but from the fire that engulfed the vehicle after the collision. The culpert in the fire was claimed to be the Telsa’s battery.
Part of the confusion surrounding the case involved the reporting that the U.S. National Transportation Safety Board (NTSB) concluded that the Tesla was being driven at a speed of “116 mph before the fiery crash”. And this finding was broadcast in large print across some local newspapers. A spokesperson for Tesla claimed “unfortunately, no car could have withstood a high-speed crash of this kind”. Then, when you read the fine details the facts turn out to be substantially different.
In a local news article (Sun Sentinel) the NTSB conclusions were that “Three seconds before impact the car was travelling at 116 mph. It slowed to 108 mph as the driver applied the brakes, and then decreased to 86 mph, according to data from the car”.
Witnesses observed that the Telsa struck a wall twice at 1313 Seabreeze Blvd, and it burst into flames after the second impact. The Tesla then continued south across the boulevard where it hit a metal light pole and stopped in a driveway. The distance between the second impact and the vehicle’s rest position was estimated at about 200 feet (61 metres). Witnesses could not put out the blaze nor could they extricate the two persons inside.
These circumstances are not much different than a widely publicized collision six years ago, on November 30, 2013, when a Porsche Carrera GT crashed on Hercules Street in Santa Clarita California, on the northern outskirts of Los Angeles. That collision caused the death of its right front passenger, Paul Walker, who was famous for his movie role in the “Fast and the Furious”. The driver of the Porsche, Roger Rodas, was travelling around a right curve of the suburban road when he lost control and the vehicle commenced a clockwise yaw, proceeding off the right roadside where the vehicle struck a tree and burst into flames.
With respect to the Walker crash I was contacted a few years ago by an unknown entity who, at first, asked me some general questions about the incident. Afterward came further and more detailed e-mails and reports, further questions and further analysis. As such general discussions often lead to a retainment by a client I did not think much of it buy the extent of subsequent contacts led to much more than general discussion. I will not discuss these details further other than to say that I conducted substantial analysis of the Paul Walker collision. Below is a general photo of the site with the words “Direction of travel” and “Crash Site” written on it.
The photo below shows the area of the site as the Porsche was already rotating clockwise and travelling toward the right curb and into the trees in the background.
The photo below shows another view of the yaw marks s the Porsche impacted the curb and then struck the tree which shows evidence of fresh contact.
The photo below shows the Porsche fully engulfed in flames while positioned against a second tree, not too distant from where it struck the curb.
In the aftermath one can see that there appears to be considerable destruction leading to the untrained conclusion that the Porsche must have been travelling at tremendous speed.
One of the conclusions from the police investigation was that the tires on the Porsche were over nine years old. Although data from an airbag control module was interrogated no actual, pre-impact speed data was available.
Without this event data investigators used what evidence was available from the geometry of the yaw marks to calculate a “critical Speed”. That speed was in the range of 90 mph. Five problems arose from this analysis. Firstly the investigators did not consider the fact that, as the Porsche was travelling through the curve its tires travelled over some “Botts Dots” or circular, elevated markers that were installed between the lanes so as to guide drivers around the curve. Secondly they used unacceptably high coefficients in their speed calculations. Thirdly they did not consider whether tires that were “over nine years old” could generate such high values of friction. Fourth, they did not acknowledge that, because of the advanced angle of rotation at the point where the first usable yaw marks were available, the speed calculation would be unstable and a critical speed calculation is generally not advised by the collision reconstruction community under such circumstances. Finally they did not conduct an independent energy analysis to confirm if the calculated speed matched with the pre-yaw, kinetic energy possessed by the Porsche. In other words, if the Porsche was truly travelling at 90 mph it must have possessed a very large amount of kinetic energy that would have to be dissipated (transferred or “removed”) in order to come to halt. Energy would be dissipated through the visible yaw marks, striking the curb, striking the trees and through production of the crush and deformation that was visible in the structure of the vehicle. Despite these problems in the analysis the news media, and the public took the police conclusions to be correct.
Returning to the Fort Lauderdale collision, a getter set of objective data was available because of the imaging of the event data recorder in the Telsa. Still, the idea was planted in the public’s understanding that, because the Telsa was travelling so quickly there could be no other conclusion reached except that the collision events were far too extreme for anyone to argue that the collision could have been survived except to the fire that erupted.
I do not have the details from the investigation of the Fort Lauderdale crash like I did in the Walker case. However any reconstructionist worth his or her salt would examine the Fort Lauderdale crash and recognize that the process of the dissipation of the vehicle’s kinetic energy should be evaluated. Much like the accounting term “follow the money trail”, so it is in the collision reconstruction that we “follow the energy trail”. In other words, we look at the full length and time of destruction to consider if any of the individual parts could be termed life-threatening.
The NTSB report indicated that the Tesla was travelling about 86 mph when the initial impact occurred but this does not mean that the total speed and kinetic energy was dissipated in a single impact. Indeed the evidence indicates that, after striking the wall on the first impact, the Telsa crossed a driveway and struck the wall a second time on the opposite side of the driveway. Furthermore, the Tesla then travelled about 200 feet (61 metres) and then crashed into a lamp post on the opposite side of the road. Thus we have at least four separate decelerations that were combined to result in the 86 mph speed loss. Even in the travel distance of 200 feet the Tesla could easily have lost 50 mph, thus were would not be much speed loss left over to suggest that either of the wall impacts were non-survivable. This is further confirmed by the fact that a rear passenger in the Tesla was ejected and survived. These facts, much like in the Paul Walker collision, demonstrate how facts mentioned in the wrong context, and coming from poor analysis, can result in erroneous conclusions.
There are many collisions occurring daily that result in vehicle fires and some of them are deadly. Some of them are deadly because it was the fire that killed the occupants. It is important not to be swayed by appearances and to look carefully at the facts before concluding that a vehicle fire was not preventable. Even a Tesla travelling at 116 mph may be involved in several impacts, each of limited severity, that occur over a long distance and over a long time, resulting in relatively minor impact severities that should not result in a fire. Think about the analogy of a commercial jetliner that is travelling at 750 mph but is able to come to stop safely because it does so over a long time and distance. One must separate those collisions where a change-in-velocity occurs very quickly and therefore can cause major injury and death, from those collisions involving an identical initial velocity but their change-in-velocity occurs gradually both in time and distance.
New Road Surface Data Available For Highbury Ave in London
On October 23, 2019, Gorski Consulting conducted testing on Highbury Ave between Hamilton Road and Highway 401 in London, Ontario to document the road’s surface conditions. This was done in a manner that has been discussed numerous times on the Gorski Consulting website. It involved the attachment of an iPhone to the structure of a 2007 Buick Allure test vehicle. An App on the iPhone was used to document the longitudinal and lateral motion of the vehicle. Video cameras documented the position of the vehicle along the road including other factors such as the vehicle speed. This article will provide a general description of the testing site, numerical results from the testing and finally a discussion of how this testing relates to results from other similar highways in Southern Ontario.
The Site
Highbury Ave is the only, four-lane, controlled-access, freeway located in the City of London, Ontario which has a population of about 390,000. This expressway is only about 5 kilometres long. To the south it connects with Highway 401 (MacDonald Cartier Freeway) which is the highest-volume freeway in Canada, stretching from Windsor to border of the Canadian Province of Quebec. To the north the Highbury Ave expressway terminates at Hamilton Road, which is an old arterial roadway that crosses at a diagonal along the south-east quadrant of London. North of Hamilton Road Highbury is no longer a controlled access freeway but a four-lane arterial.
The orange circle shows the location of the testing that was performed on Highbury Ave between Hamilton Road and Highway 401 in London, Ontario.
View of Highbury Ave at its interchange with Highway 401 at its southern terminus.
View of Highbury Ave at its intersection with Hamilton Road. This is where testing was begun. Five runs were conducted. Each run involved a southbound and northbound travel over the complete five-kilometre length of Highbury.
Highbury Ave contains two interchanges, one at Commissioners Road and another at Bradley Ave. It contains some sections of surface that are an asphalt pavement while in other sections it contains a concrete surface.
View of the southbound lanes of Highbury Ave as it approaches the interchange at Commissioners Road. This surface in this location is concrete.
Several older features of the Highbury Ave make it less safe than other similar, high-speed freeways. One sub-standard feature involves the lack of additional surface beyond the painted, yellow, edge line, as shown in the example photo below. Several decades ago Highway 401 contained a similar lacking of surface width and this resulted in many loss-of-control collisions as vehicles drifted off the surface edge. Almost all freeways of the current age contain some additional surface width including rumble strips that warn drivers when their vehicle wanders too close to the surface edge.
The width of pavement extending beyond the painted yellow edge line is virtually non-existent along some portions of Highbury Ave as shown in this example looking south toward Bradley Ave.
Tall, non-native grasses have also begun to grow in some sections of the median of Highbury Ave. While some forms of vegetation can be helpful in decelerating a vehicle that has entered a median, not all vegetation is helpful. In this case the tall grasses provide minimal deceleration while also blocking the view of drivers across the median. Vision across a median can provide an additional second or more of warning allowing a driver to detect an opposing vehicle that has entered the median and may be approaching into impact. A second or two of additional warning can be an important difference in avoiding a collision or reducing its severity.
In this northward view along Highbury Ave from just north of Bradley Ave, tall grasses growing in the median provide little deceleration for vehicles entering the median while also causing a visibility obstruction that might otherwise help drivers to avoid a cross-median collision.
These are some examples of deficiencies that plague many old freeways that have not been upgraded. The City of London is expecting to conduct a re-surfacing of Highbury Ave, likely in 2021, however it is unclear what corrections will be made to improve its substandard conditions beyond its surface.
The need for an improved surface is exemplified in the results of the Gorski Consulting surface testing that was conducted on October 23, 2019.
The Testing Results
Five test runs were conducted on Highbury Ave on October 23, 2019. Each of the five tests commenced from the intersection at Hamilton Road and progressed southward past the Highway 401 interchange. Then the test vehicle was turned around and the testing was continued northward back to the Hamilton Road intersection. The intention was to conduct the five tests at increasing speeds, from 80 to 120 km/h. Unfortunately, due to the traffic volume, interference by traffic prevented a steady speed and in many instances the test vehicle’s position had to be changed from the right lane to the left lane and back again. These changes in speed and lane position had some effects on the data making it more difficult to compare the results from one test to the other. Never-the-less some interesting results were obtained. The following five figures provide the results from the five tests.
In the past we have attempted to make it easier for readers to differentiate between “good” and “bad” road surfaces by colour coding the values. Thus green coloured values, below 0.0200 indicate good road surfaces. Black coloured values, between 0.0200 and 0.0500, indicate acceptable surfaces that will likely contain local problems. Red coloured values, above 0.0500, indicate there are likely major problems with the road surface. An exception has been made in the above table to reflect the observation that it is important for high speed expressways to contain a higher level of service, less vehicle motion and therefore lower values of rotation. Thus in the above table several values have been coded in red wherever they rise substantially above the norm for what would be expected for expressways. This is to note that any expressway with a value greater than 0.0500 must be considered of greater concern than a similar value on a lower speed road with less traffic volume.
Discussion
Without some background to the meaning of the data the significance of the posted results can be lost. Yet it is a challenge to review the background without going into a long and detailed discussion. So, the following will be an abbreviated background which will likely require readers to look at some of the previously posted articles dealing with the Road Data datafile.
In brief, the columns in the above figures labelled “Lateral Rotation” and “Longitudinal Rotation” provide an indication of how the body of the test vehicle was moved, bounced or rotated as a result of its travel over the road surface for the time period of 30 seconds. If the test vehicle was travelling at 90 km/h that would translate to 25 metres every second. So in 30 seconds the vehicle would travel about 750 metres or 3/4 of a kilometre. So the posted number of 0.0400 provides the average rate of rotation of the vehicle body over that time and distance. The number is displayed in radians per second. One radian is equal to 57.3 degrees.
Let us look at an example where the lateral rotation is noted as 0.0400. If we multiply 0.0400 by 57.3 we obtain 2.29 degrees. So this value says that, during the noted time segment of 30 seconds, the average deviation, from a level, non-rotating position, of the body of the test vehicle was 0.0400 radians or 2.29 degrees per second. Lateral rotation refers to the motion that occurs if we were to grab a hold of the door frame and began rocking the vehicle back and forth sideways. This motion is referred to “rotation about the longitudinal axis” of the vehicle because the longitudinal axis is the line that passes through the centre of the vehicle from the front license plate to the rear license plate. This sounds odd because we are talking about something “longitudinal” when we are referring to a lateral motion. But this is the technical description of what we mean by lateral rotation. Now, because we are talking about an “average”, or standard deviation, this means that individual deviations within that average could be quite different from that average. Thus, for example, if our test vehicle runs over a length of 1 metre of uneven surface this might cause a major upheaval in the vehicle’s motion during that short time period. And we would not detect that short but huge spike unless we looked more closely at the graphing of the rotation.
An example of this is shown below. This figure shows the Longitudinal (blue) and Lateral (Red) Rotations of the test vehicle in Run #1 as the vehicle was northbound and passed by the Commissioners Road overpass while travelling in the right lane. Most of the data is clustered within the range of 0.1000 to -0.1000 radians per second yet we can observe several large “spikes” in the Lateral Rotation. At least one of the spikes in the middle of the graph rises above 0.5000 radians per second.
It would be of interest to find out what specific portions of the road surface caused these spikes and this can be done with considerable accuracy because of the multiple video cameras that are attached to the test vehicle and these cameras are synchronized to the iPhone App which senses these motions.
Yet it needs to be kept in mind that the spikes occur over a very short time frame of just fractions of a second and that matters. If the motion occurs for just fraction of a second then although the rate of rotation might be very high it does not correspond to a large rotation. We would be more interested in those spikes where there are high rates of rotation but also when they exist for several samples in succession. This would mean that not only did we have a right rate of rotation but the longer time of that high rate means that the vehicle’s body actually rotated to a greater angle.
We have also mentioned in previous articles that we acknowledge use of the 2007 Buick Allure test vehicle means that the results may only be valid for that test vehicle. In other words the use of a different vehicle may result in different data and that difference could be important. There are many agencies that use specialized equipment to plot the smoothness of a road surface and because this equipment is somewhat standardized the data is comparable from one dataset to the next. While this is useful for agencies that need to evaluate matters such as wear of a surface and timing of surface maintenance those are not the same needs as ours. Our interest is in documenting how road surfaces affect the motion and therefore the stability of a typical vehicle that drives on the surface. We only need to know how our road data compares to other road data from other roads. While it may be interesting to compare the data obtained using a different vehicle that is not essential for our purposes.
A substantial amount of data has now been obtained from a variety of testing over the past 5 to 6 years. The Road Data datafile on this Gorski Consulting website now contains tested roadways from many parts of parts of Southwestern Ontario and several counties. It also contains data from expressways that are similar to Highbury Ave. We can now look at the data from several of these expressways and see how Highbury Ave compares. The table below provides a summary of testing that has been conducted just this year on these expressways.
This table enables a general comparison of the road surface conditions of these major expressways in relation to each other. It can be seen that, overall, the Lincoln Alexander Parkway in Hamilton and Highbury Ave contain the worst road surface conditions.
Toronto Street Car Damage – An Example of Successful Transparency
The safety of Toronto streetcar users was protected when its Toronto Transit Commission (TTC) properly informed the public of braking system damage on 25 of its units. This quick action should be applauded and it demonstrates how persons responsible for public safety should function. CP24 News in Toronto should also be applauded for its covering of the story.
This could easily have been an example where the TTC could have hidden the results of their inspections. Such decisions toward secrecy have spelt disaster for the City of Hamilton where its decisions to hide problems will likely lead to millions of dollars in legal fees and fines. The fact that TTC inspectors could not find the source that was causing the damage to its streetcars could have led to their concern that somehow they could be blamed – and such a defensive reaction can lead to secrecy. Instead they took the high road, informing the public that they are working on the problem while also taking the damaged streetcars out of circulation.
What if the TTC had not informed the public and there was a tragic accident resulting in injuries and possibly deaths? That is not a farfetched possibility. A large streetcar filled with many passengers perhaps leaving the track and striking pedestrians in downtown Toronto? Is that not a realistic possibility? The results could have been catastrophic. And there is no guarantee that something like this might not happen sometime in the future. But the vastly more important matter is “Due Diligence” – the fact that despite a tragedy, a public entity such as the TTC did all that it could to prevent the tragedy. How could we possibly blame the TTC if it did all that it could yet a tragedy still took place? That is far better than hiding the problem because the source could not be found.
It seems the City of Hamilton, and its lawyers, took that route of secrecy when it was revealed this week that they had known that its sewage was being dumped into a city creek but did everything to hide the extent of the problem. Are these the kinds of persons that should be employed to run the operations of systems that could kill someone, or kill many? Are these the persons we would want to run the operations of an organization such as the TTC?
This is where public recognition of the proper actions of the TTC needs to be highlighted. We congratulate the TTC and Toronto for doing the proper and ethical thing, preventing a disaster and protecting the public as they should.
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