Humboldt Broncos Multi-Fatal Bus Crash Was Likely Influenced by Lack of Proper Intersection Visibility
In a companion article (“Issues of Concern With Respect to the McElhanney Report on the Safety of the Humboldt Broncos Collision Site”) that has been posted on the Articles page of this Gorski Consulting website we have explained how the Saskatchewan Department of Transportation was likely partially at fault for the cause of the Humboldt Broncos multi-fatal bus crash on April 6, 2018 in north-eastern Saskatchewan. What has not been properly reported is that a required line of sight called an “intersection sight triangle” was not afforded to both drivers such they could not see each other in sufficient time and distance to avoid the collision. As stated by authoritative organizations such as the Transportation Association of Canada (TAC):
“From each approach to an intersection, sufficient sight distance along each intersection leg to allow vehicle operators to see approaching vehicles in time to avoid collision is required.”
The lack of proper reporting on this issue has led many Canadians to be misled about how and why the Humboldt Broncos collision occurred. Gorski Consulting has highlighted the fact that information from the police investigation of the collision has not been released even though over nine months have passed since the collision date. It is this essential information that needs to be revealed so that a proper assessment of the collision cause can be made.
Fatal Result in Rollover on Highway 6 Should Not Be Expected
The OPP released the photograph shown below of an SUV that rolled over on Highway 6 in Flamborough earlier today.
This is a classic example of a rollover that should not have resulted in fatal injuries. While we cannot see the other side of the vehicle and sometimes photographers purposely hide vehicle damage, what is visible shows evidence of a simple rollover. Simple rollovers are those that do not involve major deceleration that might occur from the impact of an wall, tree, another vehicle, etc. Such additional impacts would be recognized by the presence of crush to the vehicle. The only noticeable crush might exist at the front bumper which is missing. But that damage is minor. The minimal buckling at the front centre of the roof does not indicate a major force as such a roof is very soft and easily crushed in that manner. None of the roof pillars have been displaced and the occupant compartment retains essentially the same volume as it would prior to impact. The air bag curtains have deployed providing a further benefit to the driver’s survival and reducing the opportunity for ejection.
Simple rollovers will generate deceleration of about 0.4 to 0.6 g. When you brake your vehicle to its maximum on a dry pavement your vehicle slows down at a rate of about 0.7 g. So the slowing of a vehicle in a simple rollover is less than from maximum braking. You should not expect to sustain fatal injuries from braking so you should question why such injuries must exist in a simple rollover.
So overall, from what can be seen in this photo, the fatally injured occupant should have survived. We can never know what additional factors may be at play. Certainly anything that intruded into where the occupant was located could have a role to play. And lack of seat belt use would also be a consideration. But overall a further explanation should be provided as to why this person came to such an unfortunate circumstance.
Humboldt Broncos Tragedy Doubled By Silence
It is vitally important to understand what factors led to the tragic deaths and injuries in the Humboldt Broncos bus crash in the Canadian Province of Saskatchewan on April 7, 2018.
Previous collisions are an early warning that, if ignored, lead to current ones. And current collisions are a resetting of the alarm for future crashes. To date the Humboldt Bronco alarm has been turned off and the public has been told to get back to work. It is the public’s obligation to ask what set off the alarm in the first place. With the guilty plea of the truck driver who struck the Broncos bus those factors that were instrumental in the crash may never be made public. That secrecy becomes the enabler that allows dangerous conditions to exist.
What were the travel speeds of the vehicles on approach to the crash site? What was the speed of each vehicle at impact. What opportunity did each driver have to avoid the collision or lessen its severity? How much time did it require the truck to start from a stopped position and clear the intersection? How do other truck drivers pass through this intersection? What was the change-in-velocity of the bus and how does that match with the numbers of deaths and injuries? These are just some of the questions that need to be addressed.
Highway 401 – Adjustments to Data on Unintended Veering at Four Sites
Unintended veering out of a travel lane is rarely documented with sufficient precision. Yet this could be a cause of many collisions such as the multi-fatal collision on I-75 near Gainsville Florida that occurred on January 3, 2019. Using multiple, synchronized video cameras Gorski Consulting has documented such details at four sites along Highway 401 in Southwestern Ontario.
Example from the December 2, 2018 session showing a black car that has veered out of the westbound, right lane of Highway 401.
Preliminary data was provided in a news item posted on December 20, 2018 on this Gorski Consulting website. That data was based on videotaping at three sites. A second videotaping session was conducted at one of the sites (Westminster Drive) thus resulting in four sessions and three sites. The original table is reproduced below.
Since that posting a fifth videotaping session was conducted at a fourth site (Kenesserie Road). Additional processing of the data along with the addition of the fifth videotaping session has led to adjustments to the original table. These adjustments involved removal of some observations where the veering was simply too minimal. For example, the criterion for inclusion of a veering occurrence was with the observation of the right front tire and whether the full width of that tire was observed to move outside of the white-painted edge line of the lane. Upon closer viewing of the video we observed several instances where the veering did not reach that threshold. Thus those observations were excluded. This has resulted in the adjusted table of data below.
Not unexpectedly the observations of veering were dominated by large trucks. Of the total of 109 observations of veering, 88 involved large trucks. These vehicles are approximately 2.6 metres wide whereas typical passenger cars may only be about 1.8 metres in width while large Pick-up trucks and vans may have a width of 2.0 metres. The width of the lanes of Highway 401 are likely in the range of 3.7 to 4.0 metres. Considering these values it is easier for large trucks to veer out of a lane than smaller vehicles. Furthermore trucks hauling typical box, semi-trailers are often pushed by winds, further increasing the likelihood of such veering.
The original impetus to gathering this veering data was because, in our initial session at Westminster Drive on October 30, 2018, we were drawn to the number of vehicles that appeared to be veering to the right, out of the right lane. Now looking at the table above and comparing that session to the others, the percent of veering vehicles (2.13%) is higher than the others.
Another interesting result is that two sessions were conducted outside of the normal work week. The November 23rd session at Dillon Road was on the Friday of the US Thanksgiving Day weekend when most truckers would be spending the holidays at home. This session produced 1.62 percent veering.
The December 2, 2018 session at Westminster Drive occurred on a Sunday and it produced 1.32 percent veering, which is lower than the original session that occurred on a weekday. A further anomaly is that 50% of the veering observations (13) originated from non-trucks. This is much higher than in the other four sessions where non-trucks produced 2, 2, 4 and 0 % of the veering observations. While the number of data points is small it leads one to consider what might have caused this result other than random variance.
A factor to consider is the varying volume of heavy trucks in the five videotaping sessions. This variance in volume is shown in the table below.
It can be seen that the two non-working day sessions of November 23 and December 2, 2018 the percentage of heavy truck traffic was 25.8 and 20.6 respectively and this is far below the percentages for the other three sessions that occurred on working days. The average truck traffic percentage for those other three working day sessions (Westminster on Oct 30th = 40.4 %, Graham Road on November 5th = 48.6 % and Kenesserie Road on December 19th = 48.0 %) was 45.7%. In other words, the percentage of trucks during non-working days was about half of what it was during working days. If veering is more prominent with heavy trucks then it should affect the results of veering frequency between the non-working days and the working days.
So comparing the data between the two sessions at the Westminster site, the Oct 30th session was a working day whereas the Dec 2nd session was a non-working day. So we should expect to see less truck veering observations in the Dec 2nd session and this is what occurred. In the Oct 30th session there were 37 observations of veering trucks whereas in the Dec 2nd session there were only 13 such observations.
The explanation for the larger number of non-truck veering in the Dec 2nd session could be that there were substantially more non-trucks on the road. However it is too early to tell.
The seemingly larger number of veering trucks at the the Dillon Road session of November 23rd is not readily explainable at this time. That session was part of the Thanksgiving Day period and it can be seen that the percentage of trucks on the road was low (25.8%) and the overall travel volume was low (only 1234 vehicles). Again, these are very low numbers of data points and the results may simply be due to random variance. Never-the-less with further work and larger data some conclusions could be made in the future.
The procedures described here represent a methodology where details of vehicle motions can be documented and evaluated. The Ontario Ministry of Transportation has maintained a number of traffic counting stations for many years along Highway 401. These magnetic loop devices should be capable of providing 24-hr, 7-day-a-week data on traffic volumes, truck versus non-truck composition, gaps between traffic units and vehicle speeds. However it is highly unlikely that these stations would be capable of documenting the numbers of vehicles veering out of their lanes, how those veering actions take place and what circumstances exist before, during and after those veering actions. The methodology used by Gorski Consulting is capable of documenting such details and more. This may be particularly important when there is a need to understand how some types of collisions occur on the highway and this could lead to changes that could reduce the severity and frequency of those instances.
Multiple Child Fatalities in Florida Crash – Questions Need to be Answered Regarding Guardrail Performance & Fire
Most guardrails are inadequate to deflect tractor trailers travelling at highway speed. Also the role of a fire in the deaths of multiple children needs to be explained. This photo from yesterday’s fire on I-75 near Gainsville Florida demonstrates why information about the performance of roadways and vehicles is so critical to the public’s safety.
While many fires erupt following collisions nothing is revealed why and how they occurred and whether they were preventable.
When a major highway such as Interstate 75 in Florida is equipped only with median guardrails there is no question being asked whether such installations are deemed safe considering the percentage of heavy trucks using that highway.
These questions will inevitably remain unanswered with respect to the tragic crash that killed 5 children and 2 adults yesterday near Gainsville Florida. What is likely is that the public will be kept out of the loop about these essential facts. Fires that might be preventable are not discussed. Fatal median cross-over collisions occur but nothing of substance is provided to the public who may be their next victims.
In Ontario there are daily notices on the 511 Twitter account notifying the public about the location of vehicle fires or major collisions. These notices are only provided so that the public will stay away from the site. Nothing is said about why and how these fires started or what was the cause of those collisions. Meanwhile we await the next fully-loaded van with children that may be unable to escape a fire and then we express our sorrow over the tragedy that could not have been avoided.
Presently there is a High Tension Cable Median Barrier being installed between London and Tilbury Ontario and its safety performance needs to be known. Its safety performance does not need to be known just by the Ontario Ministry of Transportation or a select few of police, manufacturers or installers. Its safety performance needs to be known by those of the public who risk their lives in the blind trust that all will be well. The change in approach to this secrecy is of minimal consequence to the daily operations of those maintaining Highway 401 as it only requires a properly detailed documentation of the evidence and a proper release of the evidence that will educate the public. It is this education of the public that is the catalyst to essential corrections and improvements that may be necessary. A public that is ill-informed and speculative cannot bring about such essential change if it is needed.
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