Results From Bicyclist Observations on Trafalgar Multi-Use Path in London, Ontario
Residents were puzzled to observe the large number of tripods and video cameras positioned along the Trafalgar bike path on August 28, 2018 in London, Ontario.
August 28, 2018 was “Observation Day” for the Trafalgar Bike Path in east London, Ontario. This was the day that Gorski Consulting set-up 10 video cameras and documented the speeds of cyclists going up and down the slope from the north side of the new CN bridge to Trafalgar Road. The path had been previously marked at 25 metre intervals and the cameras were used to observe as cyclists passed the painted markers. Later analysis of the timecode of the synchronized cameras led to the calculation of the time that a bicycle travelled from one marker to the other. As an example if a cyclist took 3 seconds to travel the 25 metres from one marker to the next this meant that his average speed was 8.33 metres per second. By multiplying this value by 3.6 we transfer this into km/h, or 30 km/h.
View of a GoPro camera anchored to the railing of the CN bridge to document the speed of cyclists travelling up and down the slope of the path.It becomes a simple process to tally up the motions of each cyclist in a spreadsheet and this provides an indication of the variance in speeds with maximums and minimums.
The slope of the path needed to be determined and that was measured on a previous day.
View of video camera pointing southward up the slope of the bike path toward the CN bridge.
The table below shows the measurements of the slope of the path from the CN bridge to the terminus of the path at Trafalgar Road.
The observations of the cyclists on August 28, 2018 led to the creation of the table of speeds shown below.
The “Bridge to 10m” refers to the 10-metre section of the path at the north end of the CN bridge which is the portion shown in the second photo (above) in this article. The observation distances go as far as 175 metres north while the terminus of the path at Trafalgar Road is approximately 325 metres north of the CN Bridge. The observations of cyclist speeds could not be followed all the way to Trafalgar Road because it was impractical to stretch the camera positions over such a long distance. Rather it is expected that addition testing will be performed on another day to capture the cyclist motions for the remaining distance from 175 to 325 metres.
The purpose of this testing is to explore how a steep downslope can affect the speed of cyclists. In this case, northbound cyclists need to make a sharp left turn as they approach the Trafalgar underpass and we have previously mentioned how challenging that can be. Even though the steepest portion of the downslope is almost 300 metres away from that sharp left turn it still contributes to the elevated speeds as demonstrated by our coasting tests that were described in an earlier article. Even the Pottersburg Creek bridge, located just before Trafalgar Road contains a downslope of 5.8 % and this also contributes to the elevated speeds.
Above all, this is a research experiment. It is a safety lesson for those who need to consider how the characteristics of bike paths affect the public’s safety.
Example of Dangerous Situation at Trafalgar Bike Path in London, Ontario
What is so dangerous about this young female lying across the Trafalgar bike path within the dark shadow the Trafalgar Road underpass?
Gorski Consulting has expressed concern with respect to the safety of cyclists and pedestrians along London’s new multi-use path at its junction with Trafalgar Road in east London, Ontario. Those concerns have been previously highlighted in other news items on this Gorski Consulting website. An example of this danger is shown in the above photo which was taken while testing was being conducted at the path on August 24, 2018.
What is shown in the above photo is the body of a young female lying across the bike path within the shadow of the underpass of the Trafalgar Road underpass. Apparently the youngster was attempting to fish something out of the water with her hands. Other young persons were also present within the underpass but are not in view in the above photo. So why is this sight so dangerous? Well, let us take a look from a longer distance as shown in the photo below.
View looking north along the bike path upon approach to a sharp left turn that northbound cyclists would need to perform if they wished to travel underneath the Trafalgar Road underpass.
The young female is lying within the shadow of the underpass in the above photo. But how visible is she to a cyclist that would be approaching her location? Recall that testing was completed and reported by Gorski Consulting indicating that the average coasting speed of our test bicycle as it crossed the Pottersburg Creek bridge was just over 30 km/h and this is substantially higher than the average speed of recreational cyclists travelling along a typical level surface. This heightened speed is due to the downslope that exists from the CN railway overpass located about 325 metres south of Trafalgar Road.
View looking north on approach to the Pottersburg Creek bridge that is located just south of the Trafalgar Road underpass. In the background cyclists must make a sharp left turn just after they cross this bridge in order to enter into the underpass.
The photo below shows the situation as northbound cyclists would be exiting the Pottersburg Creek bridge. The cycling path comes to an abrupt end so that those wishing to proceed further north need to make a sharp left turn to proceed into the Trafalgar underpass.
View, looking north, at the north end of the Pottersburg Creek bridge where cyclists need to make a sharp left turn to proceed into the Trafalgar Road underpass.
The photo below shows the extent of the change in direction that northbound cyclists need to make as they approach the Trafalgar underpass.
View looking south from the Trafalgar underpass.
Clearly, when there are dark shadows on a sunny day a pedestrian lying across the path in the foreground would be difficult to see and even if a cyclist was able to successfully avoid such an obstacle it is quite possible that an impact could occur with the metal railing or with the concrete wall of the underpass. This is why we have expressed our concerns.
Results From Bicycle Coasting Tests on London Multi-Use Path Near Trafalgar Road
Gorski Consulting is proceeding with assessment of the safety of the new multi-use path that was completed earlier this year south of Trafalgar Road in London, Ontario. Previous postings on this website indicated our concerns that the northward downslope of the path leading to the underpass at Trafalgar Road would contribute to an increased speed of cyclists. This speed was a concern because on the approach to the underpass cyclists were forced to make an abrupt left turn into a darkened underpass with poor visibility in a location where pedestrians were found often standing within the darkened passage where they could not be readily seen. Other concerns with respect to erosion of earth onto the surface of the path at the precise point where cyclists needed to make their sharp turns were also presented.
Before proceeding with further expressions of concern there was a need to gather data on the speed of cyclists. Thus on August 24 and 25, 2018 a series of tests were performed using a hybrid bicycle instrumented with three video cameras. The tests were commenced from a stopped position at the CN railway bridge and the cycle was coasted northward down the steep downslope toward the Trafalgar underpass. The purpose of this testing was to determine what speeds would be attained as a result of the downslope irrespective of any pedaling that the cyclists might use to gain speed.
On August 24th, 14 tests were performed. It was observed that the maximum coasting speed of the cycle was reached at 150 metres north of the CN railway bridge and that maximum speed was 39.1 km/h. It was further noted that the coasting cycle reduced its speed to about 29.1 km/h at a location 275 metres north of the CN bridge. The cycle then increased its speed to 31.3 km/h as it passed over the bridge crossing the Pottersburg Creek at a loation of 300 to 325 km/h, which is located only a few metres south of the point where cyclists need to make a dramatic left turn to enter the underpass at Trafalgar Road.
The results from August 25th were similar. The maximum speed attained at the 150 metre location was 38.8 km/h, reducing to 28.5 km/h at the 275 metre marker and then increasing speed to 30.3 km/h while crossing the bridge at Pottersburg Creek.
Considering that the average speed of recreational cyclists on a level surface is below 20 km/h, these results represent a heightened speed that has an effect on the ability of cyclists to maintain control of their cycle and increases the likelihood that a collision might occur with pedestrians within the under pass or a loss-of-control incident could occur with the cycle resulting in impacts with the concrete wall of the underpass or impacts to the metal railing within the underpass.
The next step will be to document the speed of northbound cyclists as they travel along the downslope toward the Trafalgar Road underpass. The results of those observations will be reported shortly.
Failure To Recognize That Cable Barrier Did Not Prevent Engine From Crossing Hwy 401 Median
This transport truck was diverted by the cable barrier on Highway 401 near Kenesserie Road but the engine that crossed through the barrier was not stopped. That is the problem.
Highway median cross over collisions can be deadly. Therefore it is good news that a transport truck was kept within the median of Highway 401 rather than crossing into opposing lanes near Kenesserie Road on Saturday, August 18th, 2018. But the issue is more complicated than that.
The OPP reported that at about 0030 hours on Saturday an eastbound pick-up truck was hauling an engine on a flatbed trailer when its driver lost control due to the wet road conditions. The pick-up struck the newly installed high tension median barrier causing the engine to become dislodged and it flew into the opposing, westbound lanes of the highway. A westbound transport truck struck the engine and went out of control, driving into the median where it struck the cable barrier preventing the truck from travelling into the opposing eastbound lanes. This was hailed by the OPP as a success story in that there were no injuries and therefore the median barrier successfully prevented a deadly median barrier cross-over collision. Well, yes, it prevented the vehicles from crossing the median, but the celebration fails to recognize the important fact that the engine was not prevented from crossing the median, and that is a problem.
There was no description of the engine involved but it could easily have weighed a 1000 pounds. Even much less massive objects flying into opposing lanes can be deadly. What if the engine had struck a smaller vehicle such as a car or a light duty truck? Would the consequences have been just a favourable? Clearly not.
While there appear to have been some benefits to the presence of the newly-installed cable barrier, this incident does not prove that it was the right choice for installation over the more costly concrete barrier. What is needed is more information and experience from further incidents before any conclusions can be drawn. The problem is that the details of what transpires during these incidents are not provided for the public to evaluate. Nor is it likely that any such details will ever be provided. And that is another problem.
Head-on Collision Should Have Been Survivable
A fatality should not be expected in this type of head-on impact.
The OPP uploaded several photos of two vehicles involved in a fatal collision on Hwy 48 north-east of Toronto over the weekend. The photo above shows the two involved vehicles. A 25-year-old female occupant of one of the vehicles reportedly sustained fatal injuries. While the reasons why occupants do not survive such impacts may be complicated by unreported facts, the public should become critical observers of incidents like these that do not provide an obvious reason for the fatal consequence.
The safety of modern, light-duty vehicles has improved greatly over the decades such that the collisions that were deemed not survivable only 40 years ago are certainly survivable today. This is particularly true of frontal impacts of two vehicles approaching from opposite directions such as the one shown in the photo above. A distance approaching 1.5 metres from the front end of such a typical vehicle to the location of an occupied front seat is the key factor enabling the controlled ride-down of the occupants. A wide variety of safety systems can be deployed in the 1/10th of a second of such a crash that were not present 40 years ago.
In those earlier years most persons did not wear seatbelts and even if these restraints were worn they were of poor design. Similarly the frontal structures of those older vehicles did not crush in a controlled manner such that in many instances the structure of the crushed vehicle would penetrate into the occupant’s space. Air bags were also not available but even the early air bag systems were too aggressive and caused their own safety problems. Although some challenges remain, for the most part air bag systems have improved while being incorporated into the full system of other safety devices.
While it is not apparent to the general public, a key ingredient in the improved safety of head-on crashes was the implementation of “pre-tensioners” in restraint systems. In earlier days seat belt loading marks were measured by investigators to determine how they were being used at the time of an impact. That data showed that the loading did not occur until the occupant was in a “full-forward” position, similar to the position if the occupant had placed their seat in a full forward position on the seat’s adjustment track. Clearly this was not a recipe for improving the safety of occupants because the restraining was occurring too late in the crash. There are many reasons why this is not a good idea but this will not be discussed here. The point is that pre-tensioners are fired in the same manner as an air bag causing about 4 inches (10 centimetres) of webbing to be pulled toward the occupant’s body. This is a tremendous improvement in the commencement of ride down at an early stage resulting in tremendous improvement in occupant safety.
In summary the photo above shows a classic case where the frontal structures of both vehicles appear to have performed well. Although there is a lot of crush this is a good result. Crush is needed to dissipate the kinetic energy possessed by both vehicles prior to impact. The full frontal engagement of both vehicles is somewhat uncommon but it suggests that most of the kinetic energy would have been dissipated by the vehicles and that the impact force was relatively close to the centre-of-gravity of each vehicle. While this is not ideal it also allows the full frontal mass of the vehicles to be involved in the dissipation. Most head-on collisions involve in the range of a 50 percent overlap and therefore half a vehicle’s frontal structure is not helping in the controlled ride-down. So there are trade-offs.
A good crush is demonstrated by the lack of rearward displacement of the A-pillars of each vehicle. The A-pillars are those that are located on each side of the windshield. Where there is rearward displacement of such pillars there is often a compromising of the near-occupant’s seating space and this is a bad result. So seeing the lack of any A-pillar displacement is a good sign.
Proper engagement, with manageable crush on both vehicles suggests that this head-on collision should have been survivable.
Also, while there appears to be substantial crush it is not overwhelming. Examining the position of the front wheels In the wheel-wells is also a general indicator of the extent of maximum crush as well as the degree of crush of the front edges of the hood of each vehicle. All these facts point to a collision severity that was manageable.
So these facts lead to the expectation that the occupants of each vehicle should have survived the crash. So why did a 25-year-old female sustain fatal injuries in this crash? This question should not be left unanswered. While there may be reasons that have not been explained or revealed, the public should be prepared to recognize when something is not quite right in the reporting of such tragedies.
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