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TTC: Flexity Streetcars Testing & Delivery (Bombardier)

4551 Has enter service on 504 (br304am) After 14 days.
4550 & 4552 out testing.
4543 still showing its at Bathurst Loop
 
This was the 'cause' given for the Flexity that derailed from pushing a stalled CLRV: Stuart Green: "...Some debris on the tracks from the rainfall overnight"
New TTC streetcar derails in downtown Toronto while pushing older streetcar
A new TTC streetcar went off the tracks as it was pushing a stalled streetcar Tuesday morning causing major traffic delays near King and Bathurst Streets.
https://globalnews.ca/video/2886106...owntown-toronto-while-pushing-older-streetcar

Contrary to the comments made at the time, material in the flangeway was not found to be at fault in that derailment. The TTC's internal investigation found that the issue stemmed from the fact that the operator of the disabled CLRV applied the brakes in an emergency manner without notifying the operator of the pushing Flexity, which was applying power at the time, causing it to push itself off of the rails. There has since been another derailment with the same cause.

Dan
 
Why actually...

bombardier-flexity220j4u3q.jpg


Health and safety continues to be a strong focus for UITP’s members and BodyGuardTM is a safety system for light rail vehicles currently in development with Bombardier and Technical University Zurich. In the case of a possible frontal collision between vehicle and pedestrian, an airbag automatically deploys, closing the gap between road and vehicle. This technology, which prevents the pedestrian from being caught under the vehicle, has only been made possible due to the development of highly sensitive sensors.
Haha, excellent. See I thought something like this would be possible, or inevitable. But I was very much expecting angry insults and trolling about supposed impossibility.

Wonder if the Freedoms will have this, or could have it added later on.
Likely manufactured by Takata.

Love that Bombardier supply chain.

- Paul
 
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The TTC's internal investigation found that the issue stemmed from the fact that the operator of the disabled CLRV applied the brakes in an emergency manner without notifying the operator of the pushing Flexity, which was applying power at the time, causing it to push itself off of the rails. There has since been another derailment with the same cause.
Essentially the same force as a frontal collision. Caused it to derail. Twice according to your recount of what TTC found from their own investigations.

Thank you. Once again, you make my point. And that of the researchers, engineers, and other professionals who've studied and detailed exactly that, and documented it in many reports linked and discussed. The subtleties of energy absorptive buffers continue to baffle some...

Addendum:
...the flangeway was not found to be at fault in that derailment. The TTC's internal investigation found...
Do you have a link or reference?
 
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Essentially the same force as a frontal collision. Caused it to derail. Twice according to your recount of what TTC found from their own investigations.

Not necessarily, the drawbars the TTC uses to interconnect their streetcars is a completely different dynamic than two vehicle cabs coming into contact with each other. We outsiders have no idea what sort of buffers or other shock absorption mechanisms they have under the fairings. They certainly appear to be low complexity compared to the service couplers on the Freedoms, and one vehicle e-braking while the other pushes is beyond the normal use case.
 
the drawbars the TTC uses to interconnect their streetcars is a completely different dynamic than two vehicle cabs coming into contact with each other.
Based on what? If hydraulically damped couplers were used (which are designed with shock (energy) absorption on all modern designs) you may have a point, although manufacturers state in their specs as to the force absorbed and the rate, modulation can even be progressive (as in suspension systems, so you don't 'bottom' the device so easily), but for towing, since the CLRVs and Outlooks aren't coupler equipped (the CLRV's had theirs removed decades back, a whole subject in itself) a rigid tow bar is used.

And that imparts the same stress vectors on the front of the Outlook if it is being used for 'pushing' a stalled CLRV as a forward collision. Below the crash bar on the *Toronto* Outlooks is the fairing and no sign anywhere that I can find of there being a coupler per-se. And it was a 'forward collision' even if it glanced off at a vector from the front of the Outlook. The side damage on the SUV clearly shows that. There is no sign of lateral tearing on the SUV, ostensibly it was 'thrown' sideways at impact, which is consistent with the front right wheel having broken or bent axle stub and suspension arms (possibly even broken knuckles).

What isn't clear from the pics, and it would be from examining for scuffing or deformation under the front Outlook frame structure, is if momentary jamming occurred in the gap behind the fairing covers in such a way as to lift, or more likely 'tilt' the first section of the LRV (bear in mind the next section is cantilevered, so the needed force to lift the front is vastly reduced) such that even minor lateral forces on the forward bogie are enough to push the wheel flanges off the tracks.

In the case of the CLRVs, the push/tow bar is attached to the anti-climb bar. It has no absorption what-so-ever.
If someone has detailed and referenced knowledge on this, feel absolutely free to link or reference it. Meantime:
190611

(Image: Giordano Ciampini)
[...]
With inspection complete, the most delicate phase of the operation can begin: pulling the new streetcar off the flatcar. First, a spare old-style streetcar pulls up to the back of the new one and a tow bar is connected between the two.
[...]
The TTC didn’t know in advance, but Canadian Pacific delivered this new streetcar backwards, its rear end facing the unloading bay. As a result, the technicians have to take some extra steps to get the vehicle into the maintenance barn the right way around for testing.
[...]
Mihai Birjovanu, a rail vehicle analyzer with the TTC, is charged with safely towing the new streetcar off the flatcar. “Vehicles aren’t that hard to pull,” Ernst says. “They have good bearings, and on steel wheels with steel rail it only takes a few hundred pounds to move it.”
[...]
Streetcar number 4408 and the towing 4194 snake through the Hillcrest yard en route to the workshop. Because 4408 is still facing the wrong way, Birjovanu must take part in a piece of choreography that involves briefly blocking traffic on Bathurst Street. First, the coupled pair reverse into a position that allows a second spare vehicle to connect to the front of the new streetcar. Birjovanu, poking into traffic, breaks his link at the rear and 4408 is pulled forward to the entrance to the barn and backed inside. From above, the brief ballet looks like a pair of three point turns.
[...]
https://torontolife.com/city/transportation/new-ttc-streetcar-arrival-toronto/

In the case of the Outlook, as I detailed in a post prior, complete with pics, reference, link and vid, the 'collision bar/anti-climb device' (you'll see the access cover knocked off it in the post-collision pics) *may* have acted to somewhat mitigate the full concussive force. If so, it still wasn't, and evidently isn't suffice to prevent derailing the front bogie in slow speed impact...let alone high speed.

Best people think about that! It's too late to engineer a rebalance of the cantilivered forces on the front and rear bogies (the middle one is neutralized by ostensibly equal loads either end), so the obvious thing to do is to *mitigate* the forces acting on that instability.

And that's to add a reactive/absorptive bumper front and rear to reduce untoward forces on the bogies. The lower the 'reach' of such a bumper, as detailed exquisitely in the number of reports and papers I've detailed and linked, the less the tendency for the LRV to 'ride-up' on impact as well as reduce the the characteristic 'glance off' from trajectory and the amount of damage to vehicles and passengers alike.

Addendum: Note the 'gap' fibreglass skirt appears to be on hinge-arms in this pic, deployed up to allow access to place pneumatic jacks under the frame. The design appears like it was intended to mount a reactive bumper, as other Outlook models appear to have. The TTC ones are very different from the other Outlook examples in terms of the unique front end geometry. That's ostensibly to allow inter-operation in emergency situations with the CLRVs. Once the CLRVs are fully retired, and that is the reason for 'odd' geometry of Toronto's Outlooks are moot, then all the more reason to adopt the front-end safety features of the other Outlook models
https://globalnews.ca/news/2885328/...er-new-streetcar-derails-in-downtown-toronto/
 
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Based on what? If hydraulically damped couplers were used (which are designed with shock (energy) absorption on all modern designs) you may have a point, although manufacturers state in their specs as to the force absorbed and the rate, modulation can even be progressive (as in suspension systems, so you don't 'bottom' the device so easily), but for towing, since the CLRVs and Outlooks aren't coupler equipped (the CLRV's had theirs removed decades back, a whole subject in itself) a rigid tow bar is used.

And that imparts the same stress vectors on the front of the Outlook if it is being used for 'pushing' a stalled CLRV as a forward collision. Below the crash bar on the *Toronto* Outlooks is the fairing and no sign anywhere that I can find of there being a coupler per-se. And it was a 'forward collision' even if it glanced off at a vector from the front of the Outlook. The side damage on the SUV clearly shows that. There is no sign of lateral tearing on the SUV, ostensibly it was 'thrown' sideways at impact, which is consistent with the front right wheel having broken or bent axle stub and suspension arms (possibly even broken knuckles).

What isn't clear from the pics, and it would be from examining for scuffing or deformation under the front Outlook frame structure, is if momentary jamming occurred in the gap behind the fairing covers in such a way as to lift, or more likely 'tilt' the first section of the LRV (bear in mind the next section is cantilevered, so the needed force to lift the front is vastly reduced) such that even minor lateral forces on the forward bogie are enough to push the wheel flanges off the tracks.

In the case of the CLRVs, the push/tow bar is attached to the anti-climb bar. It has no absorption what-so-ever.


If someone has detailed and referenced knowledge on this, feel absolutely free to link or reference it. Meantime:


https://torontolife.com/city/transportation/new-ttc-streetcar-arrival-toronto/

In the case of the Outlook, as I detailed in a post prior, complete with pics, reference, link and vid, the 'collision bar/anti-climb device' (you'll see the access cover knocked off it in the post-collision pics) *may* have acted to somewhat mitigate the full concussive force. If so, it still wasn't, and evidently isn't suffice to prevent derailing the front bogie in slow speed impact...let alone high speed.

Best people think about that! It's too late to engineer a rebalance of the cantilivered forces on the front and rear bogies (the middle one is neutralized by ostensibly equal loads either end), so the obvious thing to do is to *mitigate* the forces acting on that instability.

And that's to add a reactive/absorptive bumper front and rear to reduce untoward forces on the bogies. The lower the 'reach' of such a bumper, as detailed exquisitely in the number of reports and papers I've detailed and linked, the less the tendency for the LRV to 'ride-up' on impact as well as reduce the the characteristic 'glance off' from trajectory and the amount of damage to vehicles and passengers alike.

Addendum: Note the 'gap' fibreglass skirt appears to be on hinge-arms in this pic, deployed up to allow access to place pneumatic jacks under the frame. The design appears like it was intended to mount a reactive bumper, as other Outlook models appear to have. The TTC ones are very different from the other Outlook examples in terms of the unique front end geometry. That's ostensibly to allow inter-operation in emergency situations with the CLRVs. Once the CLRVs are fully retired, and that is the reason for 'odd' geometry of Toronto's Outlooks are moot, then all the more reason to adopt the front-end safety features of the other Outlook models

https://globalnews.ca/news/2885328/...er-new-streetcar-derails-in-downtown-toronto/

Okay, enough with the speculation. Those of us who are interested, let's just wait for the official report. You know, the one written by experts, not armchair enthusiasts who pretend to understand (streetcar) physics.
 
Interesting: Note the "Crash Management" on the lower bumper protrusion:
[...]
https://www.ttc.ca/About_the_TTC/Commission_reports_and_information/Commission_meetings/2007/Dec_18_2007/Other/Low Floor Light Rail Vehicle - Request for Proposal - Prese.pdf

Those of us who are interested, let's just wait for the official report. You know, the one written by experts, not armchair enthusiasts who pretend to understand (streetcar) physics.
Fine, find even one from the past that's been posted. Over to you...be my guest. Even FOI requests have been denied by the TTC. The City Ombudsman has released some information on TTC issues, but that's an exception.

$32,000 and a 3-year wait: Star reporters share what it’s like trying to access public documents in Canada
https://www.thestar.com/news/gta/20...ing-to-access-public-documents-in-canada.html

So again, feel free to show where previous TTC accident reports have been published. Can't be that hard if someone of your ilk is so upset, can it?

Those of us who are interested, let's just wait for the official report
You're free to do as you like. But also feel free to produce some reference for previous issues of derailment. How long do you need?

I think you'd better read this:
https://decisions.ipc.on.ca/ipc-cipvp/orders/en/item/180283/index.do?r=AAAAAQAITU8tMzM0NyAB

If you don't like me asking questions, and posting results of researching this, then by all means block me. Thank You.
 
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Do you have a link or reference?

A friend who is quite high up in the TTC, and who was involved in the investigation into the second derailment. I doubt that I would be allowed to share the investigation if I had a copy of it however, as it is an internal document.

Dan
 
A friend who is quite high up in the TTC, and who was involved in the investigation into the second derailment. I doubt that I would be allowed to share the investigation if I had a copy of it however, as it is an internal document.

Dan
Thank you for reply. This is what many don't realize: The TTC, Metrolinx and many Cdn agencies hide information that is freely available in other nations, even the US, even though Canada and provinces claim to make the information available. Accountability and 'Open Access' is a theory.
 
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Thank you for reply. This is what many don't realize: The TTC, Metrolinx and many Cdn agencies hide information that is freely available in other nations, even the US, even though Canada and provinces claim to make the information available. Accountability and 'Open Access' is a theory.

You are right, for a lot of companies the word "Open Access" is a vague concept. I'm sure in a few years that document will be public, that's usually what happens, but that's very off topic so.
 

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