Signal passed at danger (SPAD) by passenger train TD8239, Docklands, Melbourne, Victoria, on 23 November 2020

 
  bevans Site Admin

Location: Melbourne, Australia
The ATSB is investigating a Signal Passed at Danger (SPAD) by passenger train TD8239, at Docklands, Melbourne, Victoria, on 23 November 2020.

At approximately 1634, the locomotive-hauled passenger train TD8239, travelling from Southern Cross to Wendouree (Ballarat), passed a signal that was at Stop. At the same time a VLocity train set was travelling towards Southern Cross Station and was approaching a possible conflict point with the outbound passenger train. Both trains were brought to a stop and there was no collision or injury.

This investigation is being led by Victoria’s Chief Investigator, Transport Safety (CITS). CITS conducts rail investigations in Victoria on behalf of the ATSB under the Transport Safety Investigation Act 2003.

Should safety critical information be discovered at any time during the investigation, the ATSB will immediately notify operators and regulators so appropriate and timely safety action can be taken.

A final report will be published at the conclusion of the investigation.

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  Duncs Chief Commissioner

The ATSB is investigating a Signal Passed at Danger (SPAD) by passenger train TD8239, at Docklands, Melbourne, Victoria, on 23 November 2020.

At approximately 1634, the locomotive-hauled passenger train TD8239, travelling from Southern Cross to Wendouree (Ballarat), passed a signal that was at Stop. At the same time a VLocity train set was travelling towards Southern Cross Station and was approaching a possible conflict point with the outbound passenger train. Both trains were brought to a stop and there was no collision or injury.

This investigation is being led by Victoria’s Chief Investigator, Transport Safety (CITS). CITS conducts rail investigations in Victoria on behalf of the ATSB under the Transport Safety Investigation Act 2003.

Should safety critical information be discovered at any time during the investigation, the ATSB will immediately notify operators and regulators so appropriate and timely safety action can be taken.

A final report will be published at the conclusion of the investigation.
bevans
A locomotive hauled train? I thought all the services on that line were now V Locities.
  route14 Chief Commissioner

There are three weekday peak trains that are loco hauled.
  tazzer96 Chief Commissioner

It should say towards ballarat.  It's actually a melton service.
  route14 Chief Commissioner

You are right, Melton and Bacchus Marsh.
Edit: I meant to say Bacchus Marsh but somehow typed Ballarat instead.
  The Vinelander Minister for Railways

Location: Ballan, Victoria on the Ballarat RFR Line
There are three weekday peak trains that are loco hauled.
route14

They haven't gone past my house and I can see every train going by from the comfort of my living room chair.

Mike.
  YM-Mundrabilla Minister for Railways

Location: Mundrabilla but I'd rather be in Narvik
I know that 'country trains' do not have train stop trips but what safety features do N class locos, Vlocitys and Sprinters have to guard against driver error especially in the suburban area?

Good start to the investigation will be to establish the true destination of the train not that this will affect the details of the incident.
  route14 Chief Commissioner

I remember reading that VLocities have train trip equivalent.
  historian Deputy Commissioner

I know that 'country trains' do not have train stop trips but what safety features do N class locos, Vlocitys and Sprinters have to guard against driver error especially in the suburban area?
YM-Mundrabilla

TPWS - where fitted.

Otherwise nothing.
  hbedriver Assistant Commissioner

TPWS where fitted to signals will not stop a SPAD, but will act to stop a train prior to entering any danger zone.

In this case, management decided the need to install the equipment along the platforms at Southern Cross to stop trains hitting the buffers was superior to needing to protect a complex junction subject to numerous conflicting moves. None of those eight signals were equipped with TPWS. No, I don’t know why either.

Doubtless they will now play catch up, possibly even before the final report from ATSB.
  BrentonGolding Chief Commissioner

Location: Maldon Junction
I remember reading that VLocities have train trip equivalent.
route14
TPWS is fitted to V/locity trains and it works - I have been a passenger on 2 trips where it was activated and you sure know about it especially if you are positioned near the drivers cab!

But as HBE says this acts to stop the train from entering the danger zone AFTER it has passed a signal at Red (or overspeed or whatever other reason it trips)* so it requires a buffer big enough to pull the train up BEFORE it gets to the problem / conflict ahead

In the case of a complicated set up in a very short space like the approach to Southern Cross I imagine it would be quite difficult to set up and might require very low line speeds for it to have any effect.

* I think I posted both at the time, the first time I experienced TPWS in all it's glory was an overspeed coming down grade into Sunbury on the Up so not really relevant here but the second time was when a signal reversed on the driver approaching Albion also on the Up. Our train stopped real quick due to the lower line speed at this location and so we were pulled up well short of the Metro train ahead of us that had been wrong-roaded onto the RRL where it ran out of overhead pretty quickly!
  YM-Mundrabilla Minister for Railways

Location: Mundrabilla but I'd rather be in Narvik
'Doubtless they will now play catch up, possibly even before the final report from ATSB.'
That will give plenty of time.
  YM-Mundrabilla Minister for Railways

Location: Mundrabilla but I'd rather be in Narvik
TPWS where fitted to signals will not stop a SPAD, but will act to stop a train prior to entering any danger zone.

In this case, management decided the need to install the equipment along the platforms at Southern Cross to stop trains hitting the buffers was superior to needing to protect a complex junction subject to numerous conflicting moves. None of those eight signals were equipped with TPWS. No, I don’t know why either.

Doubtless they will now play catch up, possibly even before the final report from ATSB.
hbedriver
Thanks hbedriver.
Do N class have any safety features other than Vigilance Control especially to protect against SPADs?
  historian Deputy Commissioner

But as HBE says this acts to stop the train from entering the danger zone AFTER it has passed a signal at Red (or overspeed or whatever other reason it trips)* so it requires a buffer big enough to pull the train up BEFORE it gets to the problem / conflict ahead
BrentonGolding

This is, of course, exactly the same as the mechanical train stop fitted to the EMUs.

In theory in Victoria the mechanical train stop is matched to an overlap so the train is guaranteed to stop before an obstruction. The fine print, however, is that this is only guaranteed if the train is travelling at or below the authorised speed. This is particularly problematic in four aspect territory where the train ignores a Reduce to Medium Speed/Medium Speed Warning sequence and continues at full line speed. In this case the authorised speed is Medium Speed (usually 40 km/h), but the train is travelling at a much higher speed when it SPADs. There's been at least one collision in Victoria where this was a casual factor.

Automatic train control systems have been installed for around 120 years. During all of that time there have been debates about whether it is better to trip at the signal showing danger (train stop system), or provide a warning/apply the brakes at the braking distance from the signal (e.g. GWR ATC/BR AWS).`Full supervision systems, installed since the '50s, have got around this problem but at a significant and generally unwarranted cost.
  route14 Chief Commissioner

Yes, the collision in front of Epping Depot.
  Heihachi_73 Chief Commissioner

Location: Terminating at Ringwood
It was N451 hauling an H set, for those wondering.
  kitchgp Chief Commissioner

Some locations have (or had) additional speed-proving trainstops in advance of the signal, eg Heidelberg in the single-section days and the City Loop. Might have helped with the Richmond NSW overrun incident.

From Wongm's Rail Gallery:
https://railgallery.wongm.com/signalling/E114_7553.jpg.html
  route14 Chief Commissioner

Yet Transport NSW decided to impose a speed limit of 20 km/h for the entire section before Richmond instead.
  jakar Deputy Commissioner

Location: Melbourne
TPWS where fitted to signals will not stop a SPAD, but will act to stop a train prior to entering any danger zone.

In this case, management decided the need to install the equipment along the platforms at Southern Cross to stop trains hitting the buffers was superior to needing to protect a complex junction subject to numerous conflicting moves. None of those eight signals were equipped with TPWS. No, I don’t know why either.

Doubtless they will now play catch up, possibly even before the final report from ATSB.
Thanks hbedriver.
Do N class have any safety features other than Vigilance Control especially to protect against SPADs?
YM-Mundrabilla
N class are equipped with TPWS as well.
  kuldalai Chief Commissioner

There is trade-off in terminal stations like Southern Cross in that operating speeds are relatively low BUT train movements are fairly dense especially at peak times.  So whilst it would be practicable to fit TPWS on every signal, the down side is that roads take longer to clear and re-set and fully applied TPWS would tie the peak in knots.  IIRC a lot of double protection on Low Speed signals clearing at Southern Cross was altered to avoid trains being halted unnecessarily again tying the place in knots.

Lets wait and see what the ATSB enquiry reveals.

On a similar note it appears that the diverge moves at both ends of Parwan Loop are no longer 65kmh, albeit the turnouts allow and 65kmh applied for many years ?
  Duncs Chief Commissioner

There are three weekday peak trains that are loco hauled.

They haven't gone past my house and I can see every train going by from the comfort of my living room chair.

Mike.
The Vinelander
They may be just Baccus Marsh trains.
  jakar Deputy Commissioner

Location: Melbourne
So whilst it would be practicable to fit TPWS on every signal, the down side is that roads take longer to clear and re-set and fully applied TPWS would tie the peak in knots.  
kuldalai
TPWS being fitted or not makes zero difference to the timing and operation of signals and points.

On a similar note it appears that the diverge moves at both ends of Parwan Loop are no longer 65kmh, albeit the turnouts allow and 65kmh applied for many years ?
kuldalai
Still capable of 65km/h, don't always get it though for various reasons.
  historian Deputy Commissioner

There is trade-off in terminal stations like Southern Cross in that operating speeds are relatively low BUT train movements are fairly dense especially at peak times.  So whilst it would be practicable to fit TPWS on every signal, the down side is that roads take longer to clear and re-set and fully applied TPWS would tie the peak in knots.
kuldalai

Thus spake the operator Smile

This has been a constant refrain of operators for at least 140 years. I mind the old St Louis terminal, before the new Union terminal was built around 1910. It had a very elderly electro/hydraulic/pneumatic power frame - one of the first that Union Switch & Signal erected. Over time all of the safety features were gradually stripped out because they slowed the working down. By the time the new Union terminal was commissioned all of the lockbars had gone from the points (pre track circuits), and all of the interlocking had been stripped out. It just power worked the switches and signals. As a safety device it was pretty much useless.

TPWS shouldn't have any impact on terminal operations. It's not like a CBI that can't do anything in parallel. Nor does it require time-outs, or be deliberately slow to respond.

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