Yellow signal rule

 
  steam4ian Chief Commissioner

Gentle persons

Recently Alex C stated "The EMU times are constrained by the delayed clearing of signals at level crossings which leads to preceding yellows and associated 40kph limit and the TSRs for sighting at level and ped crossings."

Since them I have done some calculations to see what speeds trains could pass a yellow signal and still pull up at a red; I have done this for varying proportions of full service braking.

v^2 = 2.a.s
4000 class service braking =   1.1 m/S/S
Distance % braking v m/S V kph
200 70% 17.55 63
300 70% 21.49 77
400 70% 24.82 89
500 70% 27.75 100
200 50% 14.83 53
300 50% 18.17 65
400 50% 20.98 76
500 50% 23.45 84
200 33% 12.05 43
300 33% 14.76 53
400 33% 17.04 61
500 33% 19.05 69

As should be apparent from the table above restricting the speed to 40 kph past a yellow is totally unnecessary in all but a few circumstances where signals are very closely spaced, ARS and the down side of Showground come to mind. In most cases the distance between sticks is 400-500 metres which for moderate braking 50% of full service allows passing speeds over 75 kph.

This is the reason why I advocate each signal having its own "passing at yellow" speed as indicated by a circular yellow plate with the speed marked on it.

The calculations are based on the usual formula for speed, acceleration and distance.

Regards
Ian

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  Aaron The Ghost of George Stephenson

Location: University of Adelaide SA
Ian you're not bringing real physics to a fabricated argument convention again are you?
  steam4ian Chief Commissioner

LOL!
  justapassenger Minister for Railways

Why bother? At some point the ETCS Level 1 in-cab signalling will get turned on and they'll have the braking curves in the cab.

The ETCS inclusion is the sole upgrade which was acquired (but still yet to be delivered) for the $105,000,000 budgeted (who knows how much was actually spent?) for signalling in the whole Seaford project. The same block lengths were used, the signals are still only three aspect, nothing else was done to make a meaningful reduction in headways (the couple of seconds to be saved by brand new controllers clearing signals a little faster doesn't count) and the switch from track circuits to axle counters would be regarded as a downgrade anywhere else in the world.
  steam4ian Chief Commissioner

Why bother? At some point the ETCS Level 1 in-cab signalling will get turned on and they'll have the braking curves in the cab.

The ETCS inclusion is the sole upgrade which was acquired (but still yet to be delivered) for the $105,000,000 budgeted (who knows how much was actually spent?) for signalling in the whole Seaford project. The same block lengths were used, the signals are still only three aspect, nothing else was done to make a meaningful reduction in headways (the couple of seconds to be saved by brand new controllers clearing signals a little faster doesn't count) and the switch from track circuits to axle counters would be regarded as a downgrade anywhere else in the world.
Justapax

In all but the "Why bother" I agree with you about the signalling. It was a monumental ....up*. Regarding signal placement and sighting they got it wrong at so many sites. You can see where provision was made with the OH masts for signal sighting but then no signal is sited there but back in its original position sighting obscured by OH masts. They had the opportunity to put the old signals back, a system which was supposedly compatible with electrification, only needed impedance bonds at the rail gaps. If they wanted a new system it could have been installed as an overlay to the existing (that's one advantage of axle counter systems) and commissioned dry while trains were operating. On D day they had simply to take the hoods of the new signals and mask the old ones

The question is, when will ETCS be installed AND operation on ALL vehicles?

In the meantime I propose a low cost fix that will work with all vehicles even when the ETCS is down, at least it has two buttocks.

Ian

* Even more so than Oaklands station or the new Marion Station swimming pool
  Aaron The Ghost of George Stephenson

Location: University of Adelaide SA
How about this question: forget when will it be installed AND operational in ALL vehicles, when will ALL drivers be trained in ETCS's use?
  defman Station Master

I'm sorry... And excuse my ignorance, but this all sounds very mathematical... But where is the human component in all of this errr... Surmising? Drivers haven't even been given a uniform update in a year or two... Where's the money for ANY of this?
  Aaron The Ghost of George Stephenson

Location: University of Adelaide SA
I think ETCS is already paid for...
  hot-axle-box Junior Train Controller

Lol....I am astounded that the acronym police on RP haven't found this thread. Smile
  Aaron The Ghost of George Stephenson

Location: University of Adelaide SA
Lol....I am astounded that the acronym police on RP haven't found this thread. Smile
hot-axle-box
The very definition of irony.
  steam4ian Chief Commissioner

Defman.

The money requirement for the speed plates is quite small. Under $100 for the reflective plate and another $100 to fix it to the post.
All up the cost would be less than one uniform for a driver.

The timing benefits would be significant probably cutting 10 mins off the round trip time allowing drivers longer crib breaks. Increased speed would enhance the public's impression of the service efficiency.

On good aspect of the present slug like performance is that as yet we have no run any passengers under the train wheels. This was my greatest fear due to the improved acceleration possible with the EUMs.

Ian
  David Peters Dr Beeching

Location: "With Hey Boy".
On good aspect of the present slug like performance is that as yet we have no run any passengers under the train wheels. This was my greatest fear due to the improved acceleration possible with the EUMs.

Ian
steam4ian
It should not take them long to run somebody down, as if the attitude of normal commuters that I have seen in place's then I am amazed that nothing has happened yet! Pedestrian gates at God knows what cost are put in and people circumvent the safety of them all to save 20 seconds. It is past a joke really! No one is that time poor that they cannot wait a minute or so to cross a track!
  Aaron The Ghost of George Stephenson

Location: University of Adelaide SA
I think ETCS is already paid for...
Aaron
I suspect nobody here, at least not myself or Mr Justapax, would be surprised to learn my FOI request on this was today ... denied ...

It would seem that despite me being both a member of the public and interested in the expenses related to the signalling upgrade paid for with public money, my request was not within the public interest. Not to worry, my request is now in the hands of a non opposition MLC of the cross bench.
  justapassenger Minister for Railways

They actually told you it was being denied instead of just letting it get sucked into a black hole? Lucky you.

When mine (asking for the identity of all bidders for the rolling stock procurement) was not responded to I made a report to ICAC. Hook, Thomas and Rossi might benefit from the knowledge that Ecuador is nice this time of year.
  David Peters Dr Beeching

Location: "With Hey Boy".
Hook is no longer with us and has not been for some time now, don't know about the other two though!
  62430 Assistant Commissioner

Location: Metro Adelaide
Hook is no longer with us and has not been for some time now, don't know about the other two though!
David Peters
Rod Hook is still with us, just not with DPTI!  He was interviewed recently on ABC, on the O-Bahn tunnel IIRC.

Alex C
  Aaron The Ghost of George Stephenson

Location: University of Adelaide SA
They actually told you it was being denied instead of just letting it get sucked into a black hole? Lucky you.

When mine (asking for the identity of all bidders for the rolling stock procurement) was not responded to I made a report to ICAC. Hook, Thomas and Rossi might benefit from the knowledge that Ecuador is nice this time of year.
justapassenger
I requested it a while back, and made several subsequent contacts to get my denial!
  Aaron The Ghost of George Stephenson

Location: University of Adelaide SA
Hook is no longer with us and has not been for some time now, don't know about the other two though!
David Peters
Rod Hook runs his own consulting company, right by a very nice cafe, I'd tell you where it is but I don't want you going there.

For the purposes of JAP's post, being outside of DPTI is not going to limit the interest of ICAC, but I don't doubt for a second Mr Hook is anything but squeaky clean here and has little to no use of Ecuador. Rod was one of the good guys, and as we know, the good guys get made the scape goat.

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