[steveintoronto]

This will crop up in the news again, doubtless, baseless or not, but one has to wonder how that Flexity derailed so readily:

JEFF GRAY QUEEN'S PARK REPORTER Globe and Mail
TORONTO
PUBLISHED JULY 25, 2008 UPDATED APRIL 27, 2018

[...]
Bombardier sources said the firm was blindsided by the TTC's announcement last week that its streetcar design had flunked a technical test of how it would handle the city's tight turns and steep hills, and by accusations from TTC chairman Adam Giambrone that Bombardier had knowingly submitted a failing bid.
[...]
The TTC had said the company submitted its computer modelling on how the streetcar would handle Toronto's tracks using parameters other than those provided by the commission. Bombardier sources yesterday said they did so because the TTC explicitly asked bidders to do that.

According to the Bombardier sources, who spoke to The Globe and Mail on condition of anonymity, the dispute centres on a two-degree difference in the angle of the top of the rail underneath the company's low-floor streetcar's wheels.

The TTC, mindful that tracks can be worn down, asked bidders to model their vehicles with a 70-degree angle. Bombardier's vehicle "did not perform optimally" under this condition, company sources acknowledged. But the sources said the TTC had asked bidders to include "alternative parameters" to show how they believe their car would best perform.

Bombardier did so, suggesting a car designed for a 72-degree wheel-track interface that the company says would work on all but a tiny fraction of the TTC's tracks, which are in the process of being replaced.[...]

https://www.theglobeandmail.com/new...isqualified-streetcar-as-safe/article1058246/

Which begs the question: Is the track on King where it crosses University (a very high wear location) up to spec?
Addendum:

Furthermore, the TTC tentatively plans on rehabilitating streetcar track on King Street between Dufferin Street and Parliament Street in stages through 2023;

https://www.toronto.ca/legdocs/mmis/2019/cc/bgrd/backgroundfile-132032.pdf

 

[Steve X]

This will crop up in the news again, doubtless, baseless or not, but one has to wonder how that Flexity derailed so readily:

https://www.theglobeandmail.com/new...isqualified-streetcar-as-safe/article1058246/

Which begs the question: Is the track on King where it crosses University (a very high wear location) up to spec?
Addendum:

https://www.toronto.ca/legdocs/mmis/2019/cc/bgrd/backgroundfile-132032.pdf

Ummmm trains and streetcars don't derail normally on straight tracks especially considering how slow the proceed through intersections. The problem with the track profiling and geometry has to do more with curves when momentum pushing the car straight while turning. It wouldn't matter too much on track conditions, when a big enough smash on an angle would drive any moving streetcar off the tracks. It wouldn't even matter if it was a SUV, pickup ,minivan or just a sedan.

Just think where will all the energy and momentum go if it didn't derail??

I think any streetcar in the world would have derailed in this collision unless it's able to absorb all the impact. That would most likely create a huge dent in the cab killing the innocent operator and multiple causality on board while pushing the streetcar backwards to smash whatever vehicle behind and/or servery crippling the frame turning the car into a write off. Alternatively if the streetcar is able to hold its stance firmly like a brick wall, the entire SUV will be crushed like a tin can killing all occupants on the SUV. In my opinion, I think it's good that the streetcar absorb small amount of the momentum and transferring it to the derailment.

ALSO, the Flexity and any new LRVs with this length are twice as long and twice the weight. With the same parameters of a CLRV, the momentum would have doubled at the same speed and be more likely to derail. Someone mention wanting long streetcars? They will even derail easier want hit on an angle.

 

[steveintoronto]

The tram hit the car. Look at the pictures. There is no sign of lateral scrape on the SUV.
The tram is over thirty times the weight of object impacted, with no sign of lateral force being transferred from the pic posted of the SUV side.

There is one distinct possibility detailed in my earlier posts and in linked and highly qualified professional studies. The frontal frame of the tram momentarily had the right front wheel of the SUV under it. The thin cowl beneath the frame was torn off laterally, ostensibly by the right side of the bumper or bodywork of the SUV. For that to happen, the wheel mentioned would be under the overhanging and unprotected clearly obvious frame portrusion.

Once again...I don't know how much simpler this can be: How did a 1500 kg vehicle being hit from the side so easily derail an LRV (tram) weighing over thirty times it's weight with the tram hitting straight on?

Vectored impact force transferred to the first segment of the LRV? There's no sign of that on the impacted SUV. Something else happened, and that is highly likely to be, according to highly accredited researchers (feel absolutely free to to contest their findings and/or methodology) and "over-ride"...which is *exactly* why anti-over-ride devices are affixed to coupled train and tram segments.

If my surmise is incorrect, then you're in a hell of a lot worse situation than you appear to believe, as it means "the fix" isn't as within easy reach by affixing a bumper as built, tested and recommended by the authors of the study.

Perhaps you'd care to set these mere mortals straight:

EXPERT REVIEW PANEL TRANSIT IDEA PROJECT 77 MARTIN P. SCHROEDER, American Public Transportation Association ANTONY R. JONES, Voith Turbo Scharfenberg GmbH & Co, United Kingdom KEITH FALK, Consultant PAUL J. MESSINA, Port Authority TransHudson, Fishkill, NY GEORGE C. HUD, LTK Engineering Services, Ambler, PA JEAN MAJOR, Dellner, INC., Charlotte, NC DOMINIQUE LE-CORRE, Alstom Transport

So be my guest....how did the derailment happen? And why won't it be repeated?

[...]
The resulting bumper from the FTA project showed marked improvements to automobile passenger safety for a variety of automobile types and collision scenarios analyzed. The results clearly show that careful selection of the front end bumper profile can significantly reduce the probability of injuries to automobile occupants. A profile that is low enough to engage the door frame structures of small and light vehicles, with an adequate vertical height to engage the same structures on taller SUVs, provided the best overall performance. Addition of a segmented corner bumper with energy absorbers further reduced the potential for injuries. Overall, the bumper design that encloses the LRV front end prevents struck vehicle override and occupant entrapment. It also helps to deflect pedestrian traffic without entrapment. [...]

Here's the study. I suggest reading it:
http://onlinepubs.trb.org/onlinepubs/IDEA/FinalReports/Transit/Transit77.pdf

Addendum: I'd also suggest considering this, complete with a video for those who have trouble reading:

Anti Climbers
In train collisions there are two distinct objectives to improve passenger safety:

• elimination of vehicle over-riding or climb over.
• prevention of uncontrolled structural collapse.

Both are achieved by managing the impact energy absorption and dissipation. Rail vehicles are now designed with controllable deformation characteristics and higher energy absorption characteristics in couplers as well as anti climbing features.

Without anti climbers one vehicle will over ride another in a serious accident. Oleo anti climbers contribute to the 'crash worthiness' of rail vehicles in two ways:

• By absorbing impact energy as collision forces rise following coupler overload. This can be by incorporating a gas hydraulic unit and /or a deforming tube in one or more stages.
• By locking vehicles together during the early part of the collision; controlling vertical movement and helping to direct forces longitudinally.

The anti climber contact faces lock together prior to any vehicle structural deformation and minimise the tendency of vehicles to climb or override.

Oleo were involved in the development of anti climbers working in conjunction with British Rail Research in the 1990's when it was established that end on collisions of railway vehicles presented the greatest hazards to passengers and that most fatalities happened at speeds of less than 60km/h, where successful prevention of over riding and energy management are possible. Extensive full size vehicle impacts were undertaken and the results can be seen in a film entitled "Oleo Crash Energy Management". [...]

https://www.oleo.co.uk/products/rail/anti-climbers

Imagine that! Absorbing impact in a controlled and progressive way. What next? Plastic disposable cowls on the front of LRVs in Canada because the natives don't know the difference?

 

[steveintoronto]

Collison Safety Improvements for Light Rail Vehicles ... - ROSA P

It's 60 pages. It might entail having to read and understand. Full report downloadable for free at this link.

The following abstract is for the ASME site paywall for the same report:

abstract

The majority of fatalities that occur from light rail vehicle (LRV) operations are occupants of automobiles that are struck by the LRVs. Recent developments of crashworthiness standards for LRVs by the American Society of Mechanical Engineers (ASME) Rail Transit Vehicle Standards Committee included consideration of a wide variety of crash scenarios including collisions between LRVs and street running automobiles. The requirements included in the standard are primarily to create an enclosed front end geometry where the struck vehicle will not be entrapped or overridden. A smooth enclosed front end profile is a primary requirement for improving the compatibility of LRVs colliding with automobiles. More recently, a study has been initiated by the Federal Transit Administration (FTA) to develop LRV front end features that further improve the crash compatibility with automobiles. The approach depends on results from computer simulation modeling of vehicle collisions across a wide variety of LRV bumper designs, some with and some without energy absorbers. Results of the study and the design of the energy absorbing bumper system are presented.

https://proceedings.asmedigitalcollection.asme.org/proceeding.aspx?articleid=1648458

And here's what looks conspicuously like the 'bar' above 'the gap' that is connected to the frontal frame member of the Outlooks:

https://www.oleo.co.uk/media/media_uploads/product-sheet-anti-climbers-LRV.pdf

Unfortunately for mixed vehicular traffic, the purpose of this is to engage other LRVs, not vehicles and pedestrians. For that, the reactive bumper shown above, and discussed at length by highly qualified personnel, is needed.

For example:

[...]

[...]

[...]

[...]

[...]

[...etc with model after model detailed and discussed...]

Link above

 

[lenaitch]

Just a thought . . . we could all wait for the results of the actual technical investigation.

 

[Steve X]

The tram hit the car. Look at the pictures. There is no sign of lateral scrape on the SUV.
The tram is over thirty times the weight of object impacted, with no sign of lateral force being transferred from the pic posted of the SUV side.

Seriously? Obviously the streetcar didn't hit a stationary SUV parked over the tracks.

Who hit who (in terms of physics) is relativity. Both vehicles were moving so they both collided and hit each other in reference of the ground.

We can also agree that the streetcar is in motion and powered itself that far off the tracks. The SUV change the direction of the streetcar.

 

[steveintoronto]

Who hit who (in terms of physics) is relativity.

Is your theory Relativity? Interesting...

 

[steveintoronto]

Just a thought . . . we could all wait for the results of the actual technical investigation.

Without bringing the situation to light in a public forum, going by the results of any previous investigation, it will not be published. There's only a few orgs in Canada that will release information freely, even if FOI mandates the release.

Anyone have any details on the last Ottawa DD bus crash investigation? How about many rail accident investigations? Often it takes the Safety Board to refer to reports not published, and the CTSB itself releases details gov't agencies refuse to.
What we still don't know about the fatal Ottawa bus crash | CBC News

Speaking of which:
Parliamentary committee wants Transportation Safety Board to oversee highway safety

ELIZABETH PAYNE Ottawa Citizen
Updated: June 11, 2019

A parliamentary committee has added its voice to those calling for the Transportation Safety Board to oversee highway safety across the country.

In a report on bus passenger safety tabled Tuesday, the Standing Committee on Transport, Infrastructure and Communities, recommended that the federal government consider expanding the mandate of the Transportation Safety Board of Canada to include the investigation of serous highway accidents, as well as all accidents involving motor vehicles designed to transport nine or more passengers.

Families of crash victims and public safety advocates have been pushing for the expansion of the Transportation Safety Board’s mandate to include highway crashes. Its work is currently limited to air, rail, marine and pipeline safety. But many safety advocates point out that highway crashes kill and injure many more people.

There was a call for the Transportation Safety Board to investigate after a double-decker OC Transpo bus crashed into a shelter at Westboro Station in January, killing three people and injuring 23. Families of victims of the Humboldt Broncos bus crash in 2018, have also called for the safety board’s involvement in highway safety.

The Transportation Safety Board did make recommendations about bus safety after an earlier deadly OC Transpo double-decker bus collided with a VIA Rail passenger train in Ottawa, in 2013. The crash killed six people.

Because the crash involved a train, it fell under the Transportation Safety Board’s mandate. Among its recommendations after that crash was that Transport Canada create crashworthy standards for large buses to help them better withstand crashes and rollovers. Parents of Humboldt victims say such standards could have protected their loved ones in a crash that killed 16 and injured 13.

The committee also recommended that Transport Canada develop bus crashworthy standards and that the Government of Canada support its ongoing efforts to do so.

Internal communications obtained by this newspaper revealed the department’s “glacial” pace in doing testing for those standards amid staff shortages and tendering red tape. Transport Canada says it has now expedited work to do that testing.

The parliamentary committee also made recommendations about improving school bus safety, including that Transport Canada be directed to study alternative seat designs aimed at improving safety, including integrated booster seats, integrated wings to reduce lateral head movement and passenger airbags.

Transport Canada, provincial and territorial authorities and others are currently studying seat belts in school buses. Seatbelts are mandated on new passenger coaches in Canada beginning in September 2020.

https://ottawacitizen.com/news/loca...tation-safety-board-to-oversee-highway-safety

https://www.ourcommons.ca/DocumentViewer/en/42-1/TRAN/news-release/10557364
https://www.ourcommons.ca/Committees/en/TRAN/StudyActivity?studyActivityId=10485212

 

[smallspy]

? That's exactly the point. There was no controlled impact. The plastic skirt tore away, and that's the extent of energy absorption on the LRV.

Where exactly was the impact controlled and absorptive?

Which is exactly how it's supposed to work. The body panels are deformable to smaller impacts, and under higher impacts get destroyed in the process. And then are easily replaced afterwards. Same idea as the CEM components on a full-sized railcar.

Had that impact happened on a CLRV or ALRV, the car would be out of service for weeks with body damage, and possibly longer if the trucks went past "full rotation" during the derailment.

Once again, the introductory paragraph of the bumper research project:
View attachment 190084
View attachment 190085
http://onlinepubs.trb.org/onlinepubs/IDEA/FinalReports/Transit/Transit77.pdf

Not every device needs to be multiple-use. Where do you put oleo struts on the sides of the vehicle to absorb the impact? How much interior space are you willing to sacrifice to do that?

I see, so slap some new plastic on that Bad Boy and he's set to go again in your books.

That's the plan. And how all modern streetcars and LRVs are designed around the planet.

I think not. Every pinion and articulated segment connection will have to be examined and with the slightest of deviation out of plumb, be replaced. Did you watch the vid of that machine being towed? It was quite damaged. I'd guess a major rebuild with it on alignment jigs. But we'll see.

They would have done a preliminary inspection on site, both before rerailing it and after doing so. As a starting point, once back at the shops, they'll do a more elaborate check, but even that will only take a day. Provided there is no major strucrural damage - and nothing that I've seen in the photos leads me to believe that is the case - much of the time in the shops is going to be spent replacing damaged panels and reprofiling or replacing the wheelsets.

Dan

 

[steveintoronto]

You keep repeating the same sorry mantra:

The body panels are deformable to smaller impacts, and under higher impacts get destroyed in the process. And then are easily replaced afterwards.

The LRV derailed, and was out of control. That that doesn't concern you is symptomatic of your continual denial of best practice. It's all about the superficial replacement of panels to you, not the physics of stability, safety and mitigating the severity of collisions.

 

[drum118]

4543 is out testing and its at Bathurst Bloor Loop at this time. There has been talk that it was damage during a test run by a vehicle and why it was MIA for a long time.

4550 was out testing yesterday while the rest were in the yard waiting for a bay in the service bay or was in the service bay.

4554 is at Lambton.

 

[crs1026]

4554 came off at Hillcrest today, 4553 is here but still awaiting delivery.

- Paul

 

[crs1026]

^I think some are overthinking this accident. Clearly, Newton would say that the streetcar, having considerable inertia, would have to go somewhere when it struck the vehicle. We don't know the exact directions and vectors of force that might have been present, so we are foolish to speculate about how the crash "should" have absorbed the energy.

Osborne's Law applies - Constants aren't, variables won't.

The point that is being missed is - no evidence that the carbody was compromised structurally. That would have been a far greater concern than the car derailing and taking a perverse path.

For those on board, it was a fairly "soft landing". I'm not going to offer judgements about whether it is preferable to harm occupants of a railcar versus harm nearby bystanders. That energy has to dissipate somehow. Maybe it's better just to prevent collisions.

(I worked with a guy who had been involved in designing the Fukushima reactors. After the tsunami, he was known to proudly announce that the hydrogen explosion blew out the pressure release panels "exactly as we designed them". It was a stretch to see that as a good thing in the bigger picture).

- Paul

 

[bbdfollower]

^I think some are overthinking this accident. Clearly, Newton would say that the streetcar, having considerable inertia, would have to go somewhere when it struck the vehicle. We don't know the exact directions and vectors of force that might have been present, so we are foolish to speculate about how the crash "should" have absorbed the energy.

Osborne's Law applies - Constants aren't, variables won't.

The point that is being missed is - no evidence that the carbody was compromised structurally. That would have been a far greater concern than the car derailing and taking a perverse path.

For those on board, it was a fairly "soft landing". I'm not going to offer judgements about whether it is preferable to harm occupants of a railcar versus harm nearby bystanders. That energy has to dissipate somehow. Maybe it's better just to prevent collisions.

(I worked with a guy who had been involved in designing the Fukushima reactors. After the tsunami, he was known to proudly announce that the hydrogen explosion blew out the pressure release panels "exactly as we designed them". It was a stretch to see that as a good thing in the bigger picture).

- Paul

^some are overthinking and not thinking at the same time, like comparing the weights of the entire LRV to a small SUV and wondering with bewilderment how the 30x weight difference could have pushed the LRV off course, not considering that the force required to deflect one set of trucks/segment is probably well within what is reasonable based on what we can guess (and this is all guessing at this point) the speed and direction of the vehicles were at impact. Once derailed the entire cars 48k kg and it’s inertia come into play - the vehicle still has to stop and IMO the operator/vehicle did an admirable job bringing it to a stop, again based of guesses about the precollision variables at hand.

 

[smallspy]

The LRV derailed, and was out of control. That that doesn't concern you is symptomatic of your continual denial of best practice. It's all about the superficial replacement of panels to you, not the physics of stability, safety and mitigating the severity of collisions.

I think that you're overracting to this. Until the cause of the accident has been released, we honestly can't claim to know what exactly happened in this instance. You claim that the car underrode the Flexity - what if the accident reconstruction didn't find that? What if the cause of the accident was simply due to the SUV impacting the streetcar at a high speed?

There are too many variables that are still unknown at this point.

Dan