NSW speed boards

[tonyp]

I do not agree with the comparison made between the metro from Tallawong to Central
with Helensburgh and Central. Most trains from Helensburgh to Central only make 6 stops.

I chose suburban semi-express services from the timetable that have a significant number of stops comparable to the metro. I specifically avoided intercity services (with the exception of the NSL where suburban trains are all stops and take well over an hour) because they have little utility for suburban travellers. I had to choose a Central Coast train with quite a few urban stops for the NSL to get something comparable to the other lines.

[tonyp]

Thanks for the excellent insight.

Few general points
- Cannot blame the existing talent pool for not knowing that 20 - 25 years ago the speed boards were higher. In my line of business things would be no different as few from the 90's would still be in the same department as today.

- The difference between 115 km/h and 160 km/h on East Hills to Glenfield is 1min, almost exactly. Increase to 130 km/h and its about half a minite, while I can see 130 km/h being a future option, 160 will not and no 160 will never happen again over the rest of the network as its simply too busy and too much work for too little gain. 160 only support some expresses, not the bulk of services with exception being East Hills to Glenfield.

- Will M sets or later be see increased Acceleration, simple answer NO! The trains were geared for 160 km/h running and then curtailed to 130 km/h running due to the OH design. To get faster acceleration the entire fleet of trains built since the late 90's will need their gearing changed and while the T sets and K sets are still in service there is no point as whats the point making one train accelerate faster than the one in front.

Additionally, the entire D set fleet was ordered with the same set-up.

R sets are limited to 130 under the wire and 160 on diesel.

A lot of people don't understand how little difference a higher maximim speed makes over shorter distances. It's just single figure minutes. I was once doing a highway trip between towns at 100 km/h and one of the run-flats got a puncture, so I had to drop to 80 km/h for the remaining half of the journey. It added only a few minutes to the trip. High top speeds are most beneficial over long distance runs.

Re gearing, which I understand, you might want to look at the Perth trains which have high maximum speeds and also good acceleration for metro-like performance at stops. They added extra power bogies to the design. Their journey time performance is the same as Sydney Metro's.

[rtt_rules]

A lot of people don't understand how little difference a higher maximim speed makes over shorter distances. It's just single figure minutes. I was once doing a highway trip between towns at 100 km/h and one of the run-flats got a puncture, so I had to drop to 80 km/h for the remaining half of the journey. It added only a few minutes to the trip. High top speeds are most beneficial over long distance runs.

Re gearing, which I understand, you might want to look at the Perth trains which have high maximum speeds and also good acceleration for metro-like performance at stops. They added extra power bogies to the design. Their journey time performance is the same as Sydney Metro's.

Yes the main issue for Sydney is not can you increase from 115 to 130 or 130 to 160 but rather get rid of the the extensive time lost to sub 80 km/h.

I would love to see higher speeds in Sydney, but the investment is substantial however the returns are not due to both the limited distances available and limited number of trains to use those routes. There are only two corridors really available and this is the EH to Glenfield which is effectively do able and the main western corridor from Redfern to Straithfield and further west. However for the later the investment is huge because the alignment is full of minor bends to get around bridges and platforms (some of which don't even exist anymore) and junctions.

For the IU trains, I think its in general alot cheaper and easier to speed this up by working on the IU corridors outside Sydney and there are across the board benefits to NSW-link services and freight.

Even if all the work was done to simply get freights up to 80km/h with sparks maybe pushing 100 km/h (or better) on the same track, there would be significant time savings removing the sub 80 km/h sections.

[tonyp]

the main western corridor from Redfern to Straithfield and further west. However for the later the investment is huge because the alignment is full of minor bends to get around bridges and platforms (some of which don't even exist anymore) and junctions.

The line from Sydney to Parramatta has an interesting history. It was originally quite straight, as it was built across open land. By the time they quadrupled and later sextupled it, urban development was solidly spread alongside it, so they had to take land from whichever side of the line they could, which explains its now snake-like profile. Parramatta-Penrith and Kingsgrove-East Hills-Glenfield-Campbelltown were built pretty straight across open countryside, though the former had to find its way NW to Blacktown before heading west.

[tonyp]

I've had to revise my table for the North Shore Line because I found one of the distance figures for the stations was via Strathfield. Cowan is in fact about 45 km from Central via the North Shore. So the relevant trains for this line are intercity ones, because the suburban operation on the North Shore doesn't have any semi-express trains from Cowan.

Tallawong 0:52 - 17
Riverstone 0:58 - 13
Cowan 1:03 - 12
Macarthur 1:03 - 16
Mount Druitt 0:50 - 9
Helensburgh 0:58 - 12

Cowan used to have a direct suburban via NSL. For example, in 1979 off peak it took 1:01 to get to Central with 23 intermediate stops! Reliability might have been a bit up the spout (in peaks it was 1:13), but otherwise how the mighty have fallen.

[Transtopic]

Before you shoot back with your long held view that an all stations metro would be faster than an equivalent distance outer suburban express service, and the metro would service every station, with the existing quad and sextup track and future extensions, an alternative all stations service would also still be available.

Certainly long lines like Macarthut and Penrith have too many stations to contemplate all stops services, but it is a fundamental tenet of Sydney's current planning that all suburbs should have equal access to the fastest possible commute and this in turn encourages more even development across the urban area. The metro is premised on this basic policy - the 30 minute city where you live within 30 minutes of your place of work etc. The two-tier operation of the suburban system doesn't serve this objective because it favours certain centres with a fast service and condemns other suburbs to a slower service and the latter won't grow local employment opportunities as well.

We can now compare the performance of the all-stations metro to semi-express suburban services as Tallawong is about the same distance from Central (45 km) as Riverstone, Berowra, Macarthur Mount Druitt and Helensburgh. Obviously one needs to compare on the basis of a similar number of intermediate stops and the various semi-expresses on those lines do have similar nimbers of stops, except services to Mount Druitt which has little more than half the nimber of stops as the others. This does, however make it the least functionally useful of the services in terms of the planning objectives.

Journey times to Central -- Number of stops

Tallawong 0:52 - 17
Riverstone 0:58 - 13
Berowra 0:59 - 12
Macarthur 1:03 - 16
Mount Druitt 0:50 - 9
Helensburgh 0:58 - 12

All slower, less stops, less functionally useful than the metro. Mount Druitt a couple of minutes faster but 8 less stops.

This discussion is about speed limits on the Sydney Trains network and nothing to do with metro, so why do you keep bringing it into the conversation?
It's irrelevant.

It's extremely unlikely that any of the ST lines you mentioned will be converted to metro and your comparisons are meaningless. A more meaningful comparison would be in a hypothetical situation if the lines in question were converted to metro, running all stations as metros do including through the inner city, and comparing it with the ST limited stop express services on the same lines if upgraded with the digital systems. I know which one I'd put my money on. It's misleading to continually make comparisons with the current ST timetable.

Track amplifications allow for the separation of fast and slow services without inhibiting faster journey times for longer distance commuters if sharing the same tracks. There is no need for the longer distance services to stop at every station and for those wishing to access a station not serviced by the express trains, there are opportunities to interchange to an all stations service at major stations. After all, we're continually brow beaten by the metro protagonists about the need to accept more interchange. I wouldn't think that a hypothetical all stations metro service from Penrith to Central with 31 intermediate stations would be a particularly attractive proposition compared with an upgraded express ST service.

[Transtopic]

The difference between 115 km/h and 160 km/h on East Hills to Glenfield is 1min, almost exactly. Increase to 130 km/h and its about half a minite, while I can see 130 km/h being a future option, 160 will not and no 160 will never happen again over the rest of the network as its simply too busy and too much work for too little gain. 160 only support some expresses, not the bulk of services with exception being East Hills to Glenfield.

- Will M sets or later be see increased Acceleration, simple answer NO! The trains were geared for 160 km/h running and then curtailed to 130 km/h running due to the OH design. To get faster acceleration the entire fleet of trains built since the late 90's will need their gearing changed and while the T sets and K sets are still in service there is no point as whats the point making one train accelerate faster than the one in front.

Additionally, the entire D set fleet was ordered with the same set-up.

R sets are limited to 130 under the wire and 160 on diesel.

It's not just about East Hills to Glenfield, but East Hills to Wolli Creek or Sydenham on the express tracks which would have a far more significant reduction in journey time with increased maximum speeds. That would be on the basis of extending the quad from Revesby to at least East Hills and preferably to Glenfield. An alternative for the East Hills to Glenfield quad would be constructing passing loop tracks around Holsworthy Station, which is the only station between East Hills and Glenfield, to allow express services to overtake the stopping service.

There's still no reason why the 160km/h speed limits couldn't be reinstated on the East Hills Line with the digital systems upgrades, as no freight runs on the line. It would only be applicable for D and R sets with further OH upgrades, with either potentially forming future SHL Intercity through services to Central instead of requiring interchange to T8 at Campbelltown. Perhaps upgraded white speed boards could be retained specifically for those services, although they will eventually be replaced with in-cab signalling.

I take issue with your assertion that the latest suburban rolling stock won't see an increase in acceleration, and by inference deceleration. They were never designed for 160km/h service speed, but 130km/h with the margin to operate at up to 110% of the design service speed, i.e. 143km/h. The design specification for acceleration/deceleration was 1.0m/sec/sec, but the built version was reduced to 0.8m/sec/sec with the proviso that it could be increased to the original design specification when requested by the rail operator, currently Sydney Trains. The acceleration/deceleration performance has got nothing to do with the maximum service speed. The K sets will soon be replaced with the Oscars cascaded down to suburban working and the T sets are next in line for replacement, which could potentially be compatible SD to operate on T4. It's not going to happen overnight though.

The D sets also have the design capability of 160km/h and I'm not aware that this has changed.

[Transtopic]

I would love to see higher speeds in Sydney, but the investment is substantial however the returns are not due to both the limited distances available and limited number of trains to use those routes. There are only two corridors really available and this is the EH to Glenfield which is effectively do able and the main western corridor from Redfern to Straithfield and further west. However for the later the investment is huge because the alignment is full of minor bends to get around bridges and platforms (some of which don't even exist anymore) and junctions.

When you say EH to Glenfield, are you referring to the sector East Hills to Glenfield or the whole East Hills Line to Glenfield? There's a difference and a quite substantial one at that.

With regard to the Western Line corridor between Strathfield and Central, @pway_master has stated that it was never assessed for the XPT design speed limits along with other lines and hence there must be the potential for significant reductions in journey times for express running on this corridor.

You have also overlooked other corridors with significant sections of quad track allowing higher express speeds, such as the T4 Illawarra Line between Wolli Creek and Hurstville and T9 in part from Strathfield to Epping. In the case of the T4 Line, Cronulla and Waterfall services have an express run from Wolli Creek to Hurstville which would benefit from an increase in maximum speeds and likewise on T9 with completion of the quad, where even with the limited overtaking opportunities between West Ryde and Epping, the semi-express peak hour service from Central to Epping is 5 minutes faster than the all stations service.

[tonyp]

From what I read from the couple of very knowledgeable people here, we're not, for various reasons, going to get maximum speeds above 130 km/h in the metropolitan area, nor is there any significant benefit in doing so in terms of journey time. A couple of other factors I'd note are, first, that the future regional/country/interstate train type that will be operating soon cannot run faster than 130 km/h under wires, nor can the suburban stock.

Second, it seems to me that Queensland and WA operators have decided that a maximum speed of 130 (WA) to 140 (Queensland) km/h is all that's required on their two lines (Mandurah and Gold Coast) where there's ample opportunity to run at 160 km/h. I believe the new C series train in Perth was considered for 160 km/h maximum speed, but it was decided to keep it at 130 because there was no significant advantage in the additional speed. I imagine also that the gearing for such a speed would reduce its acceleration capability from stop, which is more important on an all-stations train type. The only electric passenger train rated to run at 160 km/h, the NIFs, are likely to spend their lives confined to 130 km/h because there's little possibility of exceeding that on any of the electrified intercity lines due to alignment - maybe parts of the Newcastle line in the future at most.

[Transtopic]

It wouldn't worry me if the suburban electrified network is limited to 130km/h as it would at least be a big improvement on the current 115km/h limit.

It does raise the question though why the NIF (D sets) was designed for 160km/h when the OH supposedly only allows 130km/h.

[pway_master]

It wouldn't worry me if the suburban electrified network is limited to 130km/h as it would at least be a big improvement on the current 115km/h limit.

It does raise the question though why the NIF (D sets) was designed for 160km/h when the OH supposedly only allows 130km/h.

Without hijacking the thread, I can tell you that the idea was to re-introduce faster running up to 160 km/h on the faster track areas (as part of MTMS4 which has now been de-scoped), despite the minimal time gains it was still seen as desirable to have the rolling stock capable of these speeds for uplifts planned. 'Fast lanes' were planned from the North, West & South while a 'metro style' product was proposed for the T4 corridor.



Design aspects of NIF & NRF
You will note that the bogies of D & R sets possess 'yaw dampers' specifically required for speeds over 130 km/h due railway vehicle dynamics. These (and other components) require maintenance & increase the OPEX costs of such vehicles, so utilisation of their higher speeds is obviously desirable where practical from a value standpoint.

OHW Speeds
The current OHW speeds are limited to 130 km/h purely due to inexperience with operating regularly at higher speeds. All regulated constant-tension overhead wiring around Sydney is provably designed for 160 km/h (& this has been codified in standards since the 1980s). The technical aspects of up-tensioning the wires for 160 km/h is not a complex issue from an engineering perspective, especially considering local & international experience is available.

Decline of Engineering Skill
The more prevalent issue I foresee is the continual decline of in-house high-level engineering expertise within TfNSW & Sydney Trains. RailCorp previously had teams of 50-100 people in each discipline with a defined head (track, signallling, OHW etc..) These teams have been decimated to about 15-20 people per discipline as of 2025 with a large proportion of design & technical advice coming from an ever-expanding private sector (GHD, Jacobs, WSP & the like), a significant proportion of which, is comprised of foreign talent (including off-shoring of drafting & project management to the Phillipines etc.). One example is that currently, there is no capacity to design OHW internally & it is all outsourced for projects like MTMS etc.. Corporate memory loss has & is still occurring within these organisations, probablly due to the muddling of jurisdictions between TfNSW & Sydney Trains since 2013, & the fact that for the past 5 years they have primarily worked from home.

[tonyp]

Without hijacking the thread, I can tell you that the idea was to re-introduce faster running up to 160 km/h on the faster track areas (as part of MTMS4 which has now been de-scoped), despite the minimal time gains it was still seen as desirable to have the rolling stock capable of these speeds for uplifts planned. 'Fast lanes' were planned from the North, West & South while a 'metro style' product was proposed for the T4 corridor.



Design aspects of NIF & NRF
You will note that the bogies of D & R sets possess 'yaw dampers' specifically required for speeds over 130 km/h due railway vehicle dynamics. These (and other components) require maintenance & increase the OPEX costs of such vehicles, so utilisation of their higher speeds is obviously desirable where practical from a value standpoint.

OHW Speeds
The current OHW speeds are limited to 130 km/h purely due to inexperience with operating regularly at higher speeds. All regulated constant-tension overhead wiring around Sydney is provably designed for 160 km/h (& this has been codified in standards since the 1980s). The technical aspects of up-tensioning the wires for 160 km/h is not a complex issue from an engineering perspective, especially considering local & international experience is available.

Decline of Engineering Skill
The more prevalent issue I foresee is the continual decline of in-house high-level engineering expertise within TfNSW & Sydney Trains. RailCorp previously had teams of 50-100 people in each discipline with a defined head (track, signallling, OHW etc..) These teams have been decimated to about 15-20 people per discipline as of 2025 with a large proportion of design & technical advice coming from an ever-expanding private sector (GHD, Jacobs, WSP & the like), a significant proportion of which, is comprised of foreign talent (including off-shoring of drafting & project management to the Phillipines etc.). One example is that currently, there is no capacity to design OHW internally & it is all outsourced for projects like MTMS etc.. Corporate memory loss has & is still occurring within these organisations, probablly due to the muddling of jurisdictions between TfNSW & Sydney Trains since 2013, & the fact that for the past 5 years they have primarily worked from home.

Hijacking the thread? You are the substantive part of the thread and we're all grateful for it.

All Southern Highlands needs to go to Central, not just the peaks. That line is the weak link in the intercity network. Hopefully this will happen with the CAFs, which would be wasted just running as diesels.

Talking to railway engineers and chiefs some years back, I remember that an ongoing undercurrent was that the talent was going to organisations like the RTA (roads) where there was a sense of achievement and a more positive working environment. The railways were so constantly battered politically that morale was poor. People asked why would a bright graduate engineer work for the railways when they could achieve better things and have a happier working life elsewhere? Then there were the private companies like GHD who attracted droves. This would be why they're hiring from overseas. The local talent has gone elsewhere. Metro has been very exciting and attractive, but now they're starting to drift away as the current government starts stalling on the program of works. Working for government agencies in general is very frustrating and demoralising. Few professionals would stick with it for life.

[rtt_rules]

A few more general comments

- No, I didn't ignore other quad sections, I was focused on sections that at least had half a chance of exceeding 115 km/h for a sustained period that would impact on the overall transit time by at least a few minutes. The T4 and T9 corridors are rarely straight enough to warrant turning on high beam.

- Previous reference to East Hills, I based my calculation to Revesby, yes the remaining 10 km to Turrella could see faster services than currently plated, but I do not know what that currently is so I couldn't calculate how much improvement there would be. I didn't have time to google the drivers route maps. If you know the current plated speed boards then I calculate that. Overall I doubt Glenfield to Turrella will achieve more than 90 to 120 sec over the current express running. YEs this isn't to be ignored but it gets down to cost benefit. 130 km/h I think yes, lets do it, 160 km/h seems too many hoops to climb through.

North of Turella, very much doubt we will see any significant changes in run times over that quality of track and alignment.

- Top end speeds and acceleration of sets. As indicated previously and this followed a fair bit of digging. There should be no reason the sets since M should be acceleration limited even if mixing with K's and T's, it just doesn't make sense. However the technical reasons do make sense.
1) Limitation on max current draw from the OH would limit the acceleration
AND/OR
2) designed for higher speeds and as such have been geared accordingly which reduces their max acceleration. I previously provided a known design change between the first generation QR IMU 100 series rated to 140 km/h vs all the following IMU sets which are 130 km/h because the 100 series has a faster gearing and hence can go faster but drags its legs getting there. The later models are faster off the line which is what QR preferred for operational reasons when mixing with the rest of the fleets in the suburban section. Now in 25 years since the newer sets arrived, they have no regeared the 100 series.

So back to Sydney, for the newer sets to reach 130 km/h I suspect they have been geared accordingly as my intial calcs on the max current draw seemed ok, but at a cost of acceleration and I very much doubt this will be corrected.

Regardless as we have all discussed, +130 running in Sydney network has few benefits so I doubt there will be any investment to allow any set to do so, even though I would really love to ride a DD at 160 km/h through East Hills.

- Quad west of Revesby.
Yes I think this should happen, well sort of. Quad to EH, but I'm not sure its justfied further west. All trains have same performance and only the stop at Holsworthy would be an issue for the expresses. The issue with a passing lane is that the Holsworthy stop isn't long enough, you need 3 stops for an express to have a time tabled pass the doesn't slow either train. This brings back memories of old waiting at Thornleigh for the express to come and then if it was late...

Now would the Holsworthy stop be an issue? Unlikely as the EH all stoppers are slotted inbetween the SW services so even the odd express shouldn't be following by less than 5min.

4 to Glenfield has benefits especially of the Leppington branch was switched to EH and extended to Bradfield and it allows SHL. almost wish a unwired 3rd track was built to allow the future R-set movements both SHL and beyond can operate at 160 km/h.

- Main west corridor, yes this basket case of a corridor (and we wonder why the MW is being built) is a victim of its own sucess with historic successive upgrades. In some ways maybe its even cheaper reducing it back to 4 tracks to get the speeds up and putting the IU UG. Unfortunately this approach to expansion is often still being done today with some quad corridors looking like they took on the challenge to add more tracks without buying more land. (this madness is not limited to NSW either). Again the fact that nearly 60 years after a station was removed the track still curves around the former platform location is mind blowing and I've yet to see a plasuable explanation how ATO will fix this.

[Transtopic]

Without hijacking the thread, I can tell you that the idea was to re-introduce faster running up to 160 km/h on the faster track areas (as part of MTMS4 which has now been de-scoped), despite the minimal time gains it was still seen as desirable to have the rolling stock capable of these speeds for uplifts planned. 'Fast lanes' were planned from the North, West & South while a 'metro style' product was proposed for the T4 corridor.

Sorry if getting off track, but when you say that MTMS4 has been de-scoped, are you aware of what the current planning is under this program (aside from dropping 160km/h speed limits)? It would be regrettable if the proposed track amplifications were scrapped, such as completing the quad on the Northern Line from Strathfield to Hornsby as part of the Northern Sydney Freight Corridor Program which is co-funded by the Feds. Does the de-scoping also affect MTMS2 and MTMS3?

Presumably the "new eastern sector" is the T4 Line which is currently undergoing upgrading as part of the digital systems program and as I suspected, it is proposed to replace the Tangara fleet with compatible SD trains which will provide a 'metro style' service. That would be a good outcome without the cost and disruption of converting T4 to driverless metro.

Decline of Engineering Skill
The more prevalent issue I foresee is the continual decline of in-house high-level engineering expertise within TfNSW & Sydney Trains. RailCorp previously had teams of 50-100 people in each discipline with a defined head (track, signallling, OHW etc..) These teams have been decimated to about 15-20 people per discipline as of 2025 with a large proportion of design & technical advice coming from an ever-expanding private sector (GHD, Jacobs, WSP & the like), a significant proportion of which, is comprised of foreign talent (including off-shoring of drafting & project management to the Phillipines etc.). One example is that currently, there is no capacity to design OHW internally & it is all outsourced for projects like MTMS etc.. Corporate memory loss has & is still occurring within these organisations, probablly due to the muddling of jurisdictions between TfNSW & Sydney Trains since 2013, & the fact that for the past 5 years they have primarily worked from home.

This is tragic and a great bugbear of mine. Aside from the loss of corporate memory, you would think that employing outside consultants would be more expensive than doing the same work in-house. We seem to have been too reliant on Pommie imports for some time now at the expense of local expertise, although I would make an exception for Howard Collins. Former Chief Engineers of the various disciplines must be turning in their graves.
Is this still happening under the Minns' government?

You'd have to ask the question, is Transport for NSW fit for purpose when other transport agencies under its umbrella may be similarly affected?

This is really a topic for another thread.

[Transtopic]

All Southern Highlands needs to go to Central, not just the peaks. That line is the weak link in the intercity network. Hopefully this will happen with the CAFs, which would be wasted just running as diesels.

Same for SCO Intercity from Bomaderry, which I'm sure you would appreciate being SD.

[Transtopic]

No, I didn't ignore other quad sections, I was focused on sections that at least had half a chance of exceeding 115 km/h for a sustained period that would impact on the overall transit time by at least a few minutes. The T4 and T9 corridors are rarely straight enough to warrant turning on high beam.

The T9 corridor from Strathfield to West Ryde, a distance of 7km, is mostly straight track with minimal curving and could easily accommodate 130km/h. Completion of the quad on this sector to at least Epping would make a huge difference to journey times and frequencies by separating fast and slow services including freight. Although T4 isn't as straight, I'm sure existing speed limits on the express tracks between Wolli Creek and Hurstville could be increased.

So back to Sydney, for the newer sets to reach 130 km/h I suspect they have been geared accordingly as my intial calcs on the max current draw seemed ok, but at a cost of acceleration and I very much doubt this will be corrected.

Regardless as we have all discussed, +130 running in Sydney network has few benefits so I doubt there will be any investment to allow any set to do so, even though I would really love to ride a DD at 160 km/h through East Hills.

I disagree. The Waratah maximum design service speed is 130km/h and the design specification for acceleration/deceleration is 1.0m/sec/sec, which was downgraded to 0.8m/sec/sec when being built, with provision to be upgraded to the original design specification when required. It had no effect on the maximum speed and was tested up to 143km/h which is 110% of the maximum service speed as specified. I doubt if even the lower acceleration/deceleration performance has been used to date. If you haven't already read @pway_master's post, I suggest you do.

Main west corridor, yes this basket case of a corridor (and we wonder why the MW is being built) is a victim of its own sucess with historic successive upgrades. In some ways maybe its even cheaper reducing it back to 4 tracks to get the speeds up and putting the IU UG. Unfortunately this approach to expansion is often still being done today with some quad corridors looking like they took on the challenge to add more tracks without buying more land. (this madness is not limited to NSW either). Again the fact that nearly 60 years after a station was removed the track still curves around the former platform location is mind blowing and I've yet to see a plasuable explanation how ATO will fix this.

If you're referring to the Central to Strathfield corridor, then I'd hardly call it a basket case. Again, as @pway_master explained, this corridor was never assessed for the XPT speed limits, so there must be some potential to upgrade the speed limits further, even with the winding track, especially on the Main and Suburban tracks which run express services.

[rtt_rules]

All Southern Highlands needs to go to Central, not just the peaks. That line is the weak link in the intercity network. Hopefully this will happen with the CAFs, which would be wasted just running as diesels.

Same for SCO Intercity from Bomaderry, which I'm sure you would appreciate being SD.

Bomaderry I think is much further down the list of needing to get to Central. The distance is such that its not really a commuter route from south of Kiama to Central and the passenger traffic minimal even if it is. A 2/3 car set would be a very inefficent use of the already congested corridor.

However once or twice a day express I'm ok with, a bit like the Gympie Lander.

Outside peak I think the CAF's on SCO should start from Wollongong or maybe Dapto as the DD is over sized.

[rtt_rules]

The T9 corridor from Strathfield to West Ryde, a distance of 7km, is mostly straight track with minimal curving and could easily accommodate 130km/h.

Completion of the quad on this sector to at least Epping would make a huge difference to journey times and frequencies by separating fast and slow services including freight. Although T4 isn't as straight, I'm sure existing speed limits on the express tracks between Wolli Creek and Hurstville could be increased.

I agree there is some limited 115 km/h running on T9, but without track work I don't see it being alot and maybe some of the existing 115 km/h isn't suited to 130 km/h, but if it can, why not. But the time benefit we are probably spilting hairs.
https://railsafe.org.au/__data/assets/p ... 1741236176

Frequenies yes, journey times, mmm. Yes if they are following a slow service, no if they don't.

Wolli Creek to Hurtsville is a series of bends.

[rtt_rules]

I disagree. The Waratah maximum design service speed is 130km/h and the design specification for acceleration/deceleration is 1.0m/sec/sec, which was downgraded to 0.8m/sec/sec when being built, with provision to be upgraded to the original design specification when required.

It had no effect on the maximum speed and was tested up to 143km/h which is 110% of the maximum service speed as specified. I doubt if even the lower acceleration/deceleration performance has been used to date. If you haven't already read @pway_master's post, I suggest you do.

Until we can 100% confirm the reason why all the M, A and B were scaled back and more importantly can it be mitigated then its a moot point.

Signally will not be the driver for limited acceleration, its the driver for top end speed limitation.

[rtt_rules]

If you're referring to the Central to Strathfield corridor, then I'd hardly call it a basket case. Again, as @pway_master explained, this corridor was never assessed for the XPT speed limits, so there must be some potential to upgrade the speed limits further, even with the winding track, especially on the Main and Suburban tracks which run express services.

Unfortauntely it is. Nothing to do with XPT ratings, its the adhoc expansions that were done over the years as mentioned previously that have caused all the bends.

Go through the route knowledge, most speed boards are sub 80 km/h, only a few 90 - 100. I'm not sure 115 or even 130 could be squeezed out. I'm sure it could be improved, but not significantly without dropping Billions.

https://railsafe.org.au/__data/assets/p ... 1739748120

[tonyp]

Bomaderry I think is much further down the list of needing to get to Central. The distance is such that its not really a commuter route from south of Kiama to Central and the passenger traffic minimal even if it is. A 2/3 car set would be a very inefficent use of the already congested corridor.

However once or twice a day express I'm ok with, a bit like the Gympie Lander.

Outside peak I think the CAF's on SCO should start from Wollongong or maybe Dapto as the DD is over sized.

Basically children, pensioners and down and outs without a car are the only ones travelling all the way between Nowra and Sydney. In the days of the far more comfortable and faster South Coast Daylight Express it was different. However, there is a significant latent market for travel between Nowra and Wollongong (both directions), but it's presently too slow and has a break at Kiama, so it deters patronage. This would be ideal for CAF operation which can bridge the powered and unpowered sections without a break.

[Transtopic]

The T9 corridor from Strathfield to West Ryde, a distance of 7km, is mostly straight track with minimal curving and could easily accommodate 130km/h.

Completion of the quad on this sector to at least Epping would make a huge difference to journey times and frequencies by separating fast and slow services including freight. Although T4 isn't as straight, I'm sure existing speed limits on the express tracks between Wolli Creek and Hurstville could be increased.

I agree there is some limited 115 km/h running on T9, but without track work I don't see it being alot and maybe some of the existing 115 km/h isn't suited to 130 km/h, but if it can, why not. But the time benefit we are probably spilting hairs.
https://railsafe.org.au/__data/assets/p ... 1741236176

Frequenies yes, journey times, mmm. Yes if they are following a slow service, no if they don't.

Wolli Creek to Hurtsville is a series of bends.

There's no need for extra trackwork. The existing track is quite capable of 130km/h. It's the legacy signalling which is holding it back.

With quad tracks fast and slow services would be separated, so the fast services wouldn't be slowed down.

With Wolli Creek to Hurstville, there would be potential for increasing speed limits, although granted there wouldn't be huge savings in journey time. Nonetheless, it's still worth doing with the digital systems upgrades.

[Transtopic]

I disagree. The Waratah maximum design service speed is 130km/h and the design specification for acceleration/deceleration is 1.0m/sec/sec, which was downgraded to 0.8m/sec/sec when being built, with provision to be upgraded to the original design specification when required.

It had no effect on the maximum speed and was tested up to 143km/h which is 110% of the maximum service speed as specified. I doubt if even the lower acceleration/deceleration performance has been used to date. If you haven't already read @pway_master's post, I suggest you do.

Until we can 100% confirm the reason why all the M, A and B were scaled back and more importantly can it be mitigated then its a moot point.

Signally will not be the driver for limited acceleration, its the driver for top end speed limitation.

It's hardly a moot point. Most likely the acceleration/deceleration specification was scaled back because at the time the new rolling stock would be operating alongside the older S, K and T sets and there was no immediate need for the higher specification. However, the specification provided that it could be upgraded when required, i.e. when the older sets are retired. It doesn't affect the maximum service speed.

Not quite sure what you mean by your last sentence, but with ATO, acceleration/deceleration and maximum speed limits for any section of track will be controlled automatically without input from the driver, except in the case of an emergency.

[Transtopic]

If you're referring to the Central to Strathfield corridor, then I'd hardly call it a basket case. Again, as @pway_master explained, this corridor was never assessed for the XPT speed limits, so there must be some potential to upgrade the speed limits further, even with the winding track, especially on the Main and Suburban tracks which run express services.

Unfortauntely it is. Nothing to do with XPT ratings, its the adhoc expansions that were done over the years as mentioned previously that have caused all the bends.

Go through the route knowledge, most speed boards are sub 80 km/h, only a few 90 - 100. I'm not sure 115 or even 130 could be squeezed out. I'm sure it could be improved, but not significantly without dropping Billions.

https://railsafe.org.au/__data/assets/p ... 1739748120

The bends have got nothing to do with it. When you have speed limits as low as 50 or 60km/h, like around Ashfield, where you would think the track should be capable of much higher speeds, it suggests that there is room for upgrading to higher limits on the whole corridor.

The only cost is upgrading the signalling and no track upgrading is needed. Ignore the current speed boards.

[rtt_rules]

I agree there is some limited 115 km/h running on T9, but without track work I don't see it being alot and maybe some of the existing 115 km/h isn't suited to 130 km/h, but if it can, why not. But the time benefit we are probably spilting hairs.
https://railsafe.org.au/__data/assets/p ... 1741236176

Frequenies yes, journey times, mmm. Yes if they are following a slow service, no if they don't.

Wolli Creek to Hurtsville is a series of bends.

There's no need for extra trackwork. The existing track is quite capable of 130km/h. It's the legacy signalling which is holding it back.

With quad tracks fast and slow services would be separated, so the fast services wouldn't be slowed down.

With Wolli Creek to Hurstville, there would be potential for increasing speed limits, although granted there wouldn't be huge savings in journey time. Nonetheless, it's still worth doing with the digital systems upgrades.

T9
You may choose to compare the speed boards on the drivers route knowledge map against the track alignment for any section. Yes there are a couple of sections up to 2 - 4 km that 130 could be reached, but not sustained prior to the following bend.

How many CCN services are currently crawling behind a all stopper as timetabled?