Ideas and predictions for trains serving Old Oak Common station

[Bald Rick]

I think it would be pretty pointless to through-route Hex to the Western Rail Link because it's only providing a slower alternative to the GWML. If both are built one or other of the Western and Southern links probably has to terminate at T5 for capacity reasons (there are empty platforms there for that reason). As a through service the Southern provides much more benefit due to the extra access to OOC and Paddington.

AIUI the very rough plan is for one of the Southern / Western links to pick up Crossrail, and the other to pick up HEx. I forget which way round it is. Don’t forget the Southern link also has trains coming from Waterloo, and they would terminate at T5.

All rather academic, for the Southern link at least, because I can’t see it happening any time soon in the current circumstances.

 

[si404]

I think it would be pretty pointless to through-route Hex to the Western Rail Link because it's only providing a slower alternative to the GWML.

I think a Paddington-OOC-Terminal 2-Terminal 5-Slough-Maidenhead-Twyford-Reading will be about the same time as an Elizabeth line train from Reading to Paddington. I doubt people would use it as a through service.

It's not that useful for passengers, but there's operation benefits of through-running.

AIUI the very rough plan is for one of the Southern / Western links to pick up Crossrail, and the other to pick up HEx. I forget which way round it is.

Depends on who's proposing it! I'm pretty sure I've seen every combination (except both services on the Western link).

The push for Woking trains on the Southern link means HEx that way. Likewise, the push for Waterloo trains means no Elizabeth line trains on the Southern link (which would have terminated at Staines under old Network Rail plans).

I doubt TfL would be that willing to run the Western link (especially as it is likely to have Oxford trains).

 

[popeter45]

personal this is what i would do with a Western heathrow Access

Hex runs fast on fast lines from T5 to reading with Elizabeth line running the stopper, same setup as currently runs with the East side access

are there any plans for a GWML junction before OOC so services that use the fast lines could move to the Slow lines for stops while letting other fast services to pass?

 

[Bald Rick]

personal this is what i would do with a Western heathrow Access

Hex runs fast on fast lines from T5 to reading with Elizabeth line running the stopper, same setup as currently runs with the East side access

are there any plans for a GWML junction before OOC so services that use the fast lines could move to the Slow lines for stops while letting other fast services to pass?

a) the Western link connects only with the slow lines
b) no

 

[coppercapped]

Well, you've certainly always been opposed to my view, which remains the case, that the IETs should not be carrying commuter traffic and a dedicated 12-car fast commuter service should operate instead.

I have given comprehensive answers to your view before, but for the sake of new readers I shall repeat them as such assertions made with no evidence should not be unchallenged.

For the sake of this argument I assume that in the medium term (two to three years) traffic will return to pre-corona virus levels.

It is clear that capacity is constrained between Reading and London, as it is on many other routes to the capital. In this sense I have no objection to increasing capacity between Reading; all I ask is that suggestions for this increase take at least some account of the existing factors on the ground. Simply proposing, presumably additional, dedicated 12-car trains is a very, dare I say it, Trumpian, simplistic solution.

Some data. The 2011 census showed that 42,309 persons commuted into Reading from other local authorities in the UK and 32,960 persons commuted out of Reading to other local authorities in the UK by all modes. These numbers only cover ‘for work’ travel - leisure travel in all its forms is not included - and show that there is a net inflow of people to work in the Reading local government area. Restricting the mode to rail only the census showed that 6,415 persons commuted into Reading from other local authorities in the UK and 6,283 persons commuted out of Reading to other local authorities in the UK or abroad. So the rail flows are balanced. These data may be found on the ONS website here.

To these rail ‘travel to work’ figures must also be included ‘leisure’ travel and all those changing trains. The ORR data show that more than 4 million people change trains at Reading every year which is the equivalent of well over 100,000 per day; over a 16 hour period that is some 6,000 per hour. Because of the high train frequencies there is no pronounced peak in these interchange flows, although obviously more people per hour change trains during the rush hour than during the rest of the day. A proportion of these will be continuing on to Paddington - but they are not ‘Reading Commuters’ as they do not originate in Reading.

To cope with this traffic most eastbound trains call or terminate at Reading in the morning as do, obviously, the westbound local services from Paddington and Waterloo and the trains from Gatwick and Guildford. In the evening westbound trains from Paddington call at Reading not only to return people home from London but also to pick up those working or interchanging at Reading for their destinations further west.

There are three major difficulties in introducing a dedicated Reading to Paddington shuttle both mornings and evenings:

1. There is limited capacity on the Mains between Reading and London and such fast shuttles cannot run on the Reliefs because of the four essentially ‘all stations’ Crossrail trains per hour scheduled for the peaks from Reading and all the additional services joining at Airport Junction. As si404 pointed out earlier in post #150 the 2019 timetable has 16 trains per hour west of Airport Junction on the Mains all running at 125mph, on average one every 3 minutes and 45 seconds. I have no idea how many per hour you are proposing but even adding one more would be very difficult without impacting reliability especially, as I suspect, you are proposing the use of trains made up of three Class 387 units. These have a top speed of only 110mph and pathing these amid 125mph IETs will be challenging to say the least.
2. It would not be feasible to make more paths available between Reading and London or platforms at Paddington for the ‘Bletchleyite Shuttles’ by terminating expresses originating in the further reaches of the GW empire at Reading. Try explaining that to a passenger from Newport or Worcester.
3. To ensure the architypical Reading Commuter’ uses only the ‘Bletchleyite Shuttles’ there would have to be a way of separating the pedestrian flows in the station from the gatelines to the trains. Short of a significant rebuild I cannot see how this can be achieved. Currently Up Main express trains for London use the island platform 10/11 almost exclusively and only 10 can be used easily for reversing moves off the Down Main. This will block 10 for longer than a simple station stop and if it is occupied when the Down shuttle arrives all the Down trains behind the waiting shuttle - one every 3 minutes and 45 seconds don’t forget - will be held until the platform is free.

Connectivity, most importantly with HS2.

Again a buzzword.

The main driver of the redevelopments at OOC driven by the development corporation are the earnings originating from the mixture of offices and housing planned there - all of which will be made more attractive by the HS2 station and the connection to the West London, Richmond and Underground lines in the area. As a local distribution hub and as a way to improve connections from (mainly) the Birmingham area to Heathrow (there being no Birmingham to Heathrow flights at all) as well as removing some of the pressure from the inner-London connections at Euston the OOC station has a lot going for it. The remaining GWR outer-suburban trains and Crossrail will offer excellent connections for local traffic and those working in the offices.

For longer distance traffic on the Great Western routes the calculations are different. Admittedly there may be some passengers from, for example, Plymouth who would have a faster journey to Manchester or Newcastle by changing at OOC but these are edge cases. The question to be answered is how many of them will there be and does the benefit to them outweigh the dis-benefits caused to all the other passengers who wish to continue to Paddington and find that their journey is slower. There is no reason for GWR Main Line passengers to change to Crossrail at OOC, there will be a perfectly good station at Paddington and it won’t be so far to walk. It will be pointless - and I suggest counterproductive - to stop trains originating or terminating in South Wales, Bristol, Cheltenham, Worcester or Oxford at OOC as the journey time to Birmingham will be longer than the direct route. This makes a total of nine trains per hour. If these have to stop simply because the other trains stop is a classic case of the tail wagging the dog.

SNIP
This is another question Ive raised on this forum when the "oh, it was faster 50 years ago" and don't get an answer or view on. Unless people are comparing completely the same thing and taking into account modern factors then its irrelevant. How much faster should we be achieving over those timescales? 5 minutes quicker, 10? How quick should services be compared to now in 30 years?

You have comprehensively missed the point. It is not ‘how fast should the journey be?’ but ‘why should a journey in ten years time be slower than was possible in 1976, over 50 years earlier?’ Your argument is illogical - why should ‘modern factors’ make things slower? In almost every other human endeavour ‘modern factors’ make things lighter, faster or cheaper. What excuse have the railways to be different?

 

[Ianno87]

You have comprehensively missed the point. It is not ‘how fast should the journey be?’ but ‘why should a journey in ten years time be slower than was possible in 1976, over 50 years earlier?’ Your argument is illogical - why should ‘modern factors’ make things slower? In almost every other human endeavour ‘modern factors’ make things lighter, faster or cheaper. What excuse have the railways to be different?

Because in your example, you're not comparing like-for-like. Between 1976 and 2030 there are:

-Alot more trains on the network, but still only 4 tracks between Paddington and Reading. There weren't 20 main line trains per hour in 1976. For a Reading-Paddington traveller, frequency is probably a bigger factor than odd minutes on the journey time
-A whole extra stop (potentially) accommodated
-A railway that doesn't kill even nearly as many passengers it used to. A key element of modern factors you've missed is 'safer'

 

[hwl]

Because in your example, you're not comparing like-for-like. Between 1976 and 2030 there are:

-Alot more trains on the network, but still only 4 tracks between Paddington and Reading. There weren't 20 main line trains per hour in 1976. For a Reading-Paddington traveller, frequency is probably a bigger factor than odd minutes on the journey time
-A whole extra stop (potentially) accommodated
-A railway that doesn't kill even nearly as many passengers it used to. A key element of modern factors you've missed is 'safer'

Agreed.

Demand patterns between destination have changed substantially. OOC is also likely to be very popular for interchange in the future.

For the ECML orders IET wasn't/isn't primarily about journey time reduction but being able to add an extra stop on average into every journey without a time penalty (with capacity benefits too)

 

[Horizon22]

I think a Paddington-OOC-Terminal 2-Terminal 5-Slough-Maidenhead-Twyford-Reading will be about the same time as an Elizabeth line train from Reading to Paddington. I doubt people would use it as a through service.

It's not that useful for passengers, but there's operation benefits of through-running.

A lot of local demand will already be orientated around current routes that have built over time - stations on the ex-Connect service for example. Maybe some benefit for Slough / Maidenhead, but it's not operationally useful if its carting around fresh air!

 

[si404]

A lot of local demand will already be orientated around current routes that have built over time - stations on the ex-Connect service for example.

Not sure how the Connect service is relevant here. Or what your point is - it's not as if extending HEx onto Reading changes the current routes (other than HEx extending). At least no more than the Western access will.

Maybe some benefit for Slough / Maidenhead, but it's not operationally useful if its carting around fresh air!

Carting around fresh-air* because it's operationally the most convenient choice happens all the time. Running through services that make no sense end-to-end likewise.

*which is no more likely west of Heathrow than east of Heathrow. It's not as if the Thames Valley is a ghost town. Plus, unlike east of Heathrow where HEx is about passengers rather than workers, west of the airport it would be serving both.

 

[Horizon22]

Not sure how the Connect service is relevant here. Or what your point is - it's not as if extending HEx onto Reading changes the current routes (other than HEx extending). At least no more than the Western access will.

Was just considering the demand from the intermediate stations. It's very sensible if no GW expresses stop at OOC on the other hand.

 

[si404]

Was just considering the demand from the intermediate stations.

There's zero demand for say a Southall-Slough service via Heathrow taking nearly double the time of the all-stops via West Drayton service. There is, however, lots of demand for Slough-Heathrow, Southall-Heathrow and Southall-Slough.

It's very sensible if no GW expresses stop at OOC on the other hand.

Why? West of Reading to OOC passengers would be better served getting either the semi-fast GWR service, or going to Paddington and doubling back on a stopping service of some description. The journey time Reading - OOC would be the same via Heathrow as via the all-but-two stops.

The point of through service isn't primary passengers - it's operational convenience (hence why, should the southern link open, along with 2 new platforms that would give the space to allow more capacity for terminating trains, the express service will pair with the southern link - it would provide a useful link for passengers). That said, western access to T2 is very useful for passengers.

 

[Horizon22]

There's zero demand for say a Southall-Slough service via Heathrow taking nearly double the time of the all-stops via West Drayton service. There is, however, lots of demand for Slough-Heathrow, Southall-Heathrow and Southall-Slough.

Think we've crossed wires and are talking about slightly things! Of course there's no demand for that and agree that from stations west of Hayes there's certainly some direct demand, although there are currently several fast express buses.

Would a proposed through service really be quicker though with a turnaround at T5? Probably talking about 5 minutes minimum allowance for a driver to change ends. However if it linked into a Southern link service and ran through that works, but again that would need something to cater for the Western link passengers and pathing is getting tight by this point with the extra services.

Why? West of Reading to OOC passengers would be better served getting either the semi-fast GWR service, or going to Paddington and doubling back on a stopping service of some description. The journey time Reading - OOC would be the same via Heathrow as via the all-but-two stops.

The point of through service isn't primary passengers - it's operational convenience (hence why, should the southern link open, along with 2 new platforms that would give the space to allow more capacity for terminating trains, the express service will pair with the southern link - it would provide a useful link for passengers). That said, western access to T2 is very useful for passengers.

If you had to pick, which would be better - a Western link dedicated service from say Reading to Heathrow or a GWR semi-fast stopping at OOC and changing there for Heathrow?

 

[coppercapped]

Because in your example, you're not comparing like-for-like. Between 1976 and 2030 there are:

-Alot more trains on the network, but still only 4 tracks between Paddington and Reading. There weren't 20 main line trains per hour in 1976. For a Reading-Paddington traveller, frequency is probably a bigger factor than odd minutes on the journey time
-A whole extra stop (potentially) accommodated
-A railway that doesn't kill even nearly as many passengers it used to. A key element of modern factors you've missed is 'safer'

Of course I’m not comparing like with like. Why should I? The world has moved on.

So there are more trains? Then the operations and signalling systems should cope with them. To use this as a reason for stagnation or even retrogression is avoiding the question.

The higher train frequency between Reading and London is certainly a benefit to Reading passengers, but it has resulted from the higher frequencies of the services serving all those towns and cities west of Reading. I cannot think of any of the additional fast trains added over the years that originated or terminated at Reading.

Why should a whole extra stop lead to a slowing of the service? Buy trains which can cope.

Of course safety has got better - but it has got better in practically every other industry as well. Even road traffic deaths in the UK have fallen from around 7,000 per year in the mid-1970s to around 1,800 per year now. Airlines are also safer than was the case in the mid-1970s. See, for example, this graph of fatal airliner accidents taken from page 16 of the latest issue I can find of Boeing’s Statistical Summary of Commercial Jet Airplane Accidents Worldwide Operations | 1959 – 2017 which includes all types, not just Boeing products and all operators.



Railway safety is following the trend; it is also not an argument for stagnation.

If you had read my post properly you will have realised that I was writing about the effect that any extension to the time taken between Paddington and Reading will affect not only Reading to Paddington passengers but every single journey made to and from London which originates to the west of Reading. This is a very large number of people. Their interests have also to be considered.

My argument is not - and never has been - only about Reading to London passengers.

 

[Horizon22]

Why should a whole extra stop lead to a slowing of the service? Buy trains which can cope.

You can't magically change the rules of physics; instead of running at 125mph throughout, you would have to slow down go to 0mph, open and close doors and then increase back up to 125mph.

 

[coppercapped]

You can't magically change the rules of physics; instead of running at 125mph throughout, you would have to slow down go to 0mph, open and close doors and then increase back up to 125mph.

You are telling me that? I have a degree in Physics.

You've missed the context.

 

[Horizon22]

You are telling me that? I have a degree in Physics.

You've missed the context.

Which is what exactly? I've read the context but you're asking why it would lead to a slowing of the service and I think that's fairly obvious. Unless you are suggesting that timetable improvements can be made west of Reading to speed up services, but it still would increase journey times between Paddington and Reading. Even with better acceleration - and an IET is signifcanntly better than a HST at the 0-60 range, it is inevitable addition of several minutes.

Services also have increased dwell times compared to the last few decades due to increased passenger numbers. Yes rolling stock can alleviate this a little, but not always to allow 30 second dwells to remain viable.

 

[coppercapped]

Which is what exactly? I've read the context but you're asking why it would lead to a slowing of the service and I think that's fairly obvious. Unless you are suggesting that timetable improvements can be made west of Reading to speed up services, but it still would increase journey times between Paddington and Reading. Even with better acceleration - and an IET is signifcanntly better than a HST at the 0-60 range, it is inevitable addition of several minutes.

Services also have increased dwell times compared to the last few decades due to increased passenger numbers. Yes rolling stock can alleviate this a little, but not always to allow 30 second dwells to remain viable.

In my earlier post 193 I asked why the stop was needed at all:

For longer distance traffic on the Great Western routes the calculations are different. Admittedly there may be some passengers from, for example, Plymouth who would have a faster journey to Manchester or Newcastle by changing at OOC but these are edge cases. The question to be answered is how many of them will there be and does the benefit to them outweigh the dis-benefits caused to all the other passengers who wish to continue to Paddington and find that their journey is slower. There is no reason for GWR Main Line passengers to change to Crossrail at OOC, there will be a perfectly good station at Paddington and it won’t be so far to walk. It will be pointless - and I suggest counterproductive - to stop trains originating or terminating in South Wales, Bristol, Cheltenham, Worcester or Oxford at OOC as the journey time to Birmingham will be longer than the direct route. This makes a total of nine trains per hour. If these have to stop simply because the other trains stop is a classic case of the tail wagging the dog.

I understand and agree with your analysis of the physics under the current limits of train operation. However if you want to add a stop then the trains need to have better performance, possibly in conjunction with track and signalling improvements, to at least maintain the end to end times so as to not inconvenience the majority of passengers who will NOT be changing at OOC.

I agree that the IEP/IET/Class 80X trains do accelerate faster than HSTs - they are a bit more than a minute faster to Twyford from a stop at Reading than an HST. The latter used to pass Twyford at around 100mph and reach 125mph somewhere before Maidenhead, the IET is already at 125mph by Twyford. However I think you will have to agree that a one minute time saving is not a very impressive improvement after 40 years and the expenditure of several billions of capital.

 

[JonathanH]

However I think you will have to agree that a one minute time saving is not a very impressive improvement after 40 years and the expenditure of several billions of capital.

Seems rather difficult to see how there could be more than a one minute time saving without an increase in line speed. Does it need to be any quicker anyway? 23 minutes is an average speed of 94 mph.

 

[Bletchleyite]

I agree that the IEP/IET/Class 80X trains do accelerate faster than HSTs - they are a bit more than a minute faster to Twyford from a stop at Reading than an HST. The latter used to pass Twyford at around 100mph and reach 125mph somewhere before Maidenhead, the IET is already at 125mph by Twyford. However I think you will have to agree that a one minute time saving is not a very impressive improvement after 40 years and the expenditure of several billions of capital.

This assumes you consider raw speed to be the priority. I would contend that connectivity is the priority, and other than the Westcountry route (which is really a minor part of the operation) it is basically a semifast outersuburban/regional express route in practice not too dissimilar to something like Greater Anglia these days.

 

[Ianno87]

Of course I’m not comparing like with like. Why should I? The world has moved on.

And occasional trains making a headline journey time are no longer important. Frequency and capacity are.

So there are more trains? Then the operations and signalling systems should cope with them. To use this as a reason for stagnation or even retrogression is avoiding the question.

OK, show me a rules compliant timetable then, backed up with train performance that can achieve this.

The higher train frequency between Reading and London is certainly a benefit to Reading passengers, but it has resulted from the higher frequencies of the services serving all those towns and cities west of Reading. I cannot think of any of the additional fast trains added over the years that originated or terminated at Reading.

Why should a whole extra stop lead to a slowing of the service? Buy trains which can *bend the rules of space and time*.

Fixed that for you.

Of course safety has got better - but it has got better in practically every other industry as well. Even road traffic deaths in the UK have fallen from around 7,000 per year in the mid-1970s to around 1,800 per year now. Airlines are also safer than was the case in the mid-1970s. See, for example, this graph of fatal airliner accidents taken from page 16 of the latest issue I can find of Boeing’s Statistical Summary of Commercial Jet Airplane Accidents Worldwide Operations | 1959 – 2017 which includes all types, not just Boeing products and all operators.

View attachment 78398

Railway safety is following the trend; it is also not an argument for stagnation.

.

It is following the trend *because* of safety measures and systems imposed, which *all* have an implication on speed and journey times.

 

[CW2]

When considering journey times, it is important to realise that it isn't just the station-to-station time which counts. (That is the time we see in the timetables, and is easiest for us to focus on in discussions such as this, but that would be a mistake). Professional forecasters use "Generalised Journey Time" for door-to-door journeys, which is defined as Journey time + service interval penalty + interchange penalty. So if I travelled from a location in the outskirts of Bristol to an office in Canary Wharf, the sum might look something like:
Walking time from home in Bristol to bus stop + time spent waiting for bus + bus journey time to stop nearest to Temple Meads + walking time to platform + time spent waiting for train + train journey time Temple Meads - Old Oak Common + transfer time at OOC station + waiting time for Crossrail train + Crossrail train journey time + walking time from Canary Wharf station to office.

If you live on a bus route where there are buses every few minutes, you don't need to worry about missing one, but if there are only 2 or 3 per hour then you would tend to turn up early at the bus stop to ensure you catch it OK. So the demand modellers will penalise infrequent services. The same applies on rail - hence the rail network gets filled up with a frequent service of short trains, rather than less-frequent longer trains.

If a particular leg of the journey is overcrowded, a percentage of passengers may need to wait for the next train, so again a journey time penalty can be applied.

To bring all this back to Old Oak Common, the modelling shows there is a net overall benefit to stopping the GWML fast lines services there, because of the wide range of interchange possibilities. Yes, it is possible to look at individual traffic flows and moan that they are going to be a few minutes later into Paddington. Overall however OOC Interchange is a good idea.

If I can allow myself a bold prediction, OOC could grow to become a much busier station than Paddington, which would be demoted to the status of turn-back siding for Old Oak Common.

 

[plugwash]

Is there any information on how old oak common will be treated from a ticketing perspective. I.E. will it be considered a london station or not (if it's not then it would save some people money on their tickets but also likely mean that some journeys were unticketable because their "not london" routes don't go anywhere near london)

 

[Horizon22]

In my earlier post 193 I asked why the stop was needed at all:

I understand and agree with your analysis of the physics under the current limits of train operation. However if you want to add a stop then the trains need to have better performance, possibly in conjunction with track and signalling improvements, to at least maintain the end to end times so as to not inconvenience the majority of passengers who will NOT be changing at OOC.

There are probably 2 (or 3) options

1. Stop a GWR express at OOC - I would suggest only one with others needing to change at Reading.
2a. Don't bother with a stop at OOC; passengers to change at Paddington for local service to OOC
2b. Don't bother with a stop at OOC; passengers to change at Reading for local/semi-express service to OOC

 

[Ianno87]

Is there any information on how old oak common will be treated from a ticketing perspective. I.E. will it be considered a london station or not (if it's not then it would save some people money on their tickets but also likely mean that some journeys were unticketable because their "not london" routes don't go anywhere near london)

Far too early to know that yet. I don't even think Crossrail's ticketing arrangements (i.w. where "London Terminals" is valid to) have been confirmed yet!

 

[plugwash]

If I can allow myself a bold prediction, OOC could grow to become a much busier station than Paddington, which would be demoted to the status of turn-back siding for Old Oak Common.

An interesting question that. There will be some journeys for which OOC is definately better, but for other's i'd imagine it will be a wash or even worse. Paddington links to quite a few different underground lines.

It's also worth noting that the rail planning tools do not count changes between underground lines when determining the number of changes. This effectively gives the tube an unfair advantage in Journey planning.

 

[Ianno87]

An interesting question that. There will be some journeys for which OOC is definately better, but for other's i'd imagine it will be a wash or even worse. Paddington links to quite a few different underground lines.

It's also worth noting that the rail planning tools do not count changes between underground lines when determining the number of changes. This effectively gives the tube an unfair advantage in Journey planning.

Although Londoners think nothing if changing tubes extra times if it makes the journey faster.

 

[si404]

Probably talking about 5 minutes minimum allowance for a driver to change ends.

Which is difficult in 2 platforms when you are turning round 10tph and need to provide some respite.

Reading and Paddington have a bit (though not that much) space to do this. You can do a 10 minute turn around at each end fine, but the western side would be terrible if you try and stretch 52 into 75 (to keep an even every 15 minutes) - there's not space to spend 10 minutes turning round at T5, nor 15 at Reading.

However if it linked into a Southern link service and ran through that works, but again that would need something to cater for the Western link passengers and pathing is getting tight by this point with the extra services.

Not really, as you spend the money connecting, fitting out and staffing the other two platforms that can be built in the box. Running through services removes that big cost from the Western link. Afterwards you can have trains turning round as there's space, though plans seem to be two different through services and no terminating trains.

If you had to pick, which would be better - a Western link dedicated service from say Reading to Heathrow or a GWR semi-fast stopping at OOC and changing there for Heathrow?

????

I think you are right when you say:

Think we've crossed wires and are talking about slightly things!

The GWR semi-fast I'm talking about is a relief line service: (Oxford) - Didcot - all stops - Reading - Twyford - Maidenhead - Slough - Hayes & Harlington - Ealing Broadway - (OOC) - Paddington
There's zero reason to change at OOC to get to Heathrow from the west on that service - you'd change at Hayes. Or, more likely, just drive as going via Hayes is slower: and this is why the Western link is key - Slough to T5 in 6 or 7 minutes rather than 23 minutes with a change is far better at beating the car!

The Western link from Reading would be 26 minutes to T5, which is the same time to get to Paddington stopping at OOC on a fast train. T2 would be 50-50 as to whether OOC or Reading is better to change from a fast GWR to a Heathrow service. And there's far more to stop at OOC for than just the Heathrow service - it's a far easier change than Paddington onto the Elizabeth line, and HS2 is important for pretty much all the fast GWR trains (not the super-fast whose first stop is Bristol Parkway - that would want OOC for Heathrow access, having skipped Reading) as Slough, Reading, Didcot and Swindon to the North is going to be faster via OOC than Oxford or Cheltenham.

 

[coppercapped]

When considering journey times, it is important to realise that it isn't just the station-to-station time which counts. (That is the time we see in the timetables, and is easiest for us to focus on in discussions such as this, but that would be a mistake). Professional forecasters use "Generalised Journey Time" for door-to-door journeys, which is defined as Journey time + service interval penalty + interchange penalty. So if I travelled from a location in the outskirts of Bristol to an office in Canary Wharf, the sum might look something like:
Walking time from home in Bristol to bus stop + time spent waiting for bus + bus journey time to stop nearest to Temple Meads + walking time to platform + time spent waiting for train + train journey time Temple Meads - Old Oak Common + transfer time at OOC station + waiting time for Crossrail train + Crossrail train journey time + walking time from Canary Wharf station to office.

If you live on a bus route where there are buses every few minutes, you don't need to worry about missing one, but if there are only 2 or 3 per hour then you would tend to turn up early at the bus stop to ensure you catch it OK. So the demand modellers will penalise infrequent services. The same applies on rail - hence the rail network gets filled up with a frequent service of short trains, rather than less-frequent longer trains.

If a particular leg of the journey is overcrowded, a percentage of passengers may need to wait for the next train, so again a journey time penalty can be applied.

To bring all this back to Old Oak Common, the modelling shows there is a net overall benefit to stopping the GWML fast lines services there, because of the wide range of interchange possibilities. Yes, it is possible to look at individual traffic flows and moan that they are going to be a few minutes later into Paddington. Overall however OOC Interchange is a good idea.

If I can allow myself a bold prediction, OOC could grow to become a much busier station than Paddington, which would be demoted to the status of turn-back siding for Old Oak Common.

One of the frequent memes in these forums is that Paddington is too far from the centre of London to be useful.

OOC will be even further from the centre than Paddington...

Stratford and its newly developed area has not yet overtaken Liverpool Street although it is also very well connected and it has been going since the Millennium. I doubt that your prediction will come true, central London will still offer much more than OOC ever will. It's largely going to be offices, houses and flats, right? Boring.

The major point of the station at OOC is to give people using HS2 an easy way of getting to or leaving the Central Line corridor through London without overloading the existing tube and bus network at Euston in an area that also caters for Kings Cross and St Pancras traffic. It means that HS2 can reach Euston without the cost of having to build Crossrail 2 to add capacity to the local network. The OOC station will also offer easy connections from HS2 to Heathrow and the commercially successful towns in the lower Thames Valley using the local service on the GW Relief lines as well as the Richmond and West London lines without having to double back from Euston.

In this context it will certainly be busy. I still maintain that the 'connectivity' benefits of OOC are largely irrelevant to those long distance GW expresses I referred to in earlier posts. If the model says otherwise (you write as if you have seen the results) then I should love to have sight of the assumptions. I have been involved in enough models in my lifetime to want to be very, very careful in understanding what the initial conditions are and what the sensitivity analyses come up with.

 

[CW2]

One of the frequent memes in these forums is that Paddington is too far from the centre of London to be useful.

OOC will be even further from the centre than Paddington...

Stratford and its newly developed area has not yet overtaken Liverpool Street although it is also very well connected and it has been going since the Millennium. I doubt that your prediction will come true, central London will still offer much more than OOC ever will. It's largely going to be offices, houses and flats, right? Boring.

Up to a point. I'd argue that Liverpool Street is within easy walking distance of quite a lot of commercial and touristic locations, whereas Paddington is only a destination for people who live or work there. Paddington's main purpose is as a transport interchange. OOC will offer a wider range of connections than Paddington does. Most people arriving at Paddington on the long-distance GWML services need to connect to travel deeper into other parts of London. As I mentioned in an earlier post, I suspect the travel may be asymmetrical morning / evening, as passengers would prefer to go via Paddington in the evening so as to have a better chance of getting a seat.

The major point of the station at OOC is to give people using HS2 an easy way of getting to or leaving the Central Line corridor through London without overloading the existing tube and bus network at Euston in an area that also caters for Kings Cross and St Pancras traffic. It means that HS2 can reach Euston without the cost of having to build Crossrail 2 to add capacity to the local network. The OOC station will also offer easy connections from HS2 to Heathrow and the commercially successful towns in the lower Thames Valley using the local service on the GW Relief lines as well as the Richmond and West London lines without having to double back from Euston.

HS2 was never linked with the building of Crossrail 2.

Remember that HS2 was originally tasked with serving Heathrow. Once that proved unattractive, linking at OOC into the Heathrow Express services became a necessity (political necessity rather than operational / financial). It's hard to see how you can stop Heathrow Express services on the FL at OOC without stopping everything else as well, such is the density of services / short headways on the GWML.

The case for stopping GWML expresses at OOC is marginal. The additional stop causes a journey time increase for anybody staying on the train through to Paddington. Overall, that is trumped by the journey time benefits for those people interchanging at OOC.

 

[Ianno87]

Up to a point. I'd argue that Liverpool Street is within easy walking distance of quite a lot of commercial and touristic locations, whereas Paddington is only a destination for people who live or work there. Paddington's main purpose is as a transport interchange. OOC will offer a wider range of connections than Paddington does. Most people arriving at Paddington on the long-distance GWML services need to connect to travel deeper into other parts of London. As I mentioned in an earlier post, I suspect the travel may be asymmetrical morning / evening, as passengers would prefer to go via Paddington in the evening so as to have a better chance of getting a seat.



HS2 was never linked with the building of Crossrail 2.

Remember that HS2 was originally tasked with serving Heathrow. Once that proved unattractive, linking at OOC into the Heathrow Express services became a necessity (political necessity rather than operational / financial).

I think the causality is kind of the other way around. Once it was identified that Old Oak Common provided Heathrow links to all 18 HS2 services per hour (rather than one or two per hour) basically as good as going to a "Heathrow" station then a shuttle to the terminal, the Heathrow spur basically bit the dust as it is alot if cost without much further advantage.

The case for stopping GWML expresses at OOC is marginal. The additional stop causes a journey time increase for anybody staying on the train through to Paddington. Overall, that is trumped by the journey time benefits for those people interchanging at OOC.

Old Oak will of course likely be a shorter interchange time/distance between GWML and Crossrail.

Homeward-bound Reading passengers will particulaly benefit - just go to the Down Main island at Old Oak and get the next train as if it were a tube line, rather than Paddington platform roulette / stampede.