Class 745 Stadler FLIRTs

[43074]

The WAML and GEML recasts can be done separately, and ideally will be to spread the workload for everyone.

But I wouldn’t want to be the person advising the stakeholders, or the Secretary of State, that they have to wait 3 1/2 years...

You see I was referring to this post in which you said:

No chance before then. It also has to be done at a different time to the WA recast, which has to tie in with the ECML recast, and I’ll leave it there for the speculators.

Now not being a betting man but with a feel for things in that area at the moment, I wouldn't bet on ECML being recast in Dec 2021 given progress, or lack thereof, with various important aspects of infrastructure work associated with that recast. Which would indeed make Dec 2023 realistic for GEML all things considered?

And there's no obvious way for Grant Schapps to "accelerate" delivery of the timetable without compromising performance when Priti Patel and others behind the taskforce are told they will just have to wait!

 

[Railperf]

11

You wouldn’t believe how difficult it was to close that crossing, nor how much it cost to run each year!



Often caused by signaller workload - if the signaller is on a call dealing with (say) a level crossing matter or a line blockage, he/she needs to concentrate on that and not setting routes. No ARS east of Marks Tey either.

How much manual intervention does ARS need on a typical London to Norwich service when everything is running to plan?

 

[Bald Rick]

11

How much manual intervention does ARS need on a typical London to Norwich service when everything is running to plan?

None from London to Marks Tey, and then there’s no ARS...

 

[RailWonderer]

Journeycheck is now showing the 745/1s with no first class as having a trolley service in the rear coach. I'm glad they have done this and I hope it continues when the full timetable is resumed. Could a trolley service run on a 755 if need be?

All 100mph from Ipswich to Chelmsford (apart from 70 through Manningtree & 90mph through Colchester) then a mix of 85/90 to Shenfield, 90 Shenfield to Maryland then 80 to Mile End.

What's stopping it from being all 100mph non-stop?
Most rolling stock on the GEML has never been used to its full potential because of these rules. It can't just be level crossings because those only prevent 110mph + running from what I've heard.

 

[Bald Rick]

What's stopping it from being all 100mph non-stop?
Most rolling stock on the GEML has never been used to its full potential because of these rules. It can't just be level crossings because those only prevent 110mph + running from what I've heard.

Lots of things at Colchester and Manningtree (and Ipswich, and Stowmarket) variously track alignment, signal spacing, bridge strength, level crossings.

Going above 100mph is an issue for every level crossing on the line. Above 100mph Auto half barriers are prohibited (and there’s a lot of them), and all crossings of any form must have active protection. But it’s not just level crossings - the OLE is not fit for more than 200, neither is much of the track (or more accurately, what’s beneath the track), nor the signal spacing, and so on.

 

[dk1]

What's stopping it from being all 100mph non-stop?
Most rolling stock on the GEML has never been used to its full potential because of these rules. It can't just be level crossings because those only prevent 110mph + running from what I've heard.

Signal spacing and the sheer density of mixed traffic on this very busy section of railway.

 

[Class 170101]

None from London to Marks Tey, and then there’s no ARS...

Hasn't something been installed in the Colchester area to handle the increased traffic, I see some of the route codes have changed in the last few years in preparation for something like ARS.

Going above 100mph is an issue for every level crossing on the line. Above 100mph Auto half barriers are prohibited (and there’s a lot of them), and all crossings of any form must have active protection. But it’s not just level crossings - the OLE is not fit for more than 200, neither is much of the track (or more accurately, what’s beneath the track), nor the signal spacing, and so on.

Signal spacing and the sheer density of mixed traffic on this very busy section of railway.

Is signal spacing the issue it used to be? How was it solved on the MML for Meridians to run at 125mph? I don't recall any resignalling schemes on the MML beyond a few extra banner repeaters as the Meridians could still stop from 125mph in the same distance compared to previous trains with poorer brakes from lower speeds.

Could Class 745s stop from 110mph compared to Class 90s at 100mph in the same distance I wonder?

 

[Railperf]

Could Class 745s stop from 110mph compared to Class 90s at 100mph in the same distance I wonder?

Very likely they could - but as mentioned before - the cost of upgrading track, OLE, removing or upgrading the AHB level crossings etc, would have to be justified by additional revenue. You can't compare traffic levels with the MML, which is much longer Intercity route serving connecting four major cities with London - five cities in fact if you add on the trains that serve Leeds.

 

[43096]

Is signal spacing the issue it used to be? How was it solved on the MML for Meridians to run at 125mph? I don't recall any resignalling schemes on the MML beyond a few extra banner repeaters as the Meridians could still stop from 125mph in the same distance compared to previous trains with poorer brakes from lower speeds.

MML 125mph is not restricted to 222s.

 

[Railperf]

Hasn't something been installed in the Colchester area to handle the increased traffic, I see some of the route codes have changed in the last few years in preparation for something like ARS.




Is signal spacing the issue it used to be? How was it solved on the MML for Meridians to run at 125mph? I don't recall any resignalling schemes on the MML beyond a few extra banner repeaters as the Meridians could still stop from 125mph in the same distance compared to previous trains with poorer brakes from lower speeds.

Could Class 745s stop from 110mph compared to Class 90s at 100mph in the same distance I wonder?

I'm told fitting a single banner repeater is an eye watering sum!

 

[dk1]

Hasn't something been installed in the Colchester area to handle the increased traffic, I see some of the route codes have changed in the last few years in preparation for something like ARS.




Is signal spacing the issue it used to be? How was it solved on the MML for Meridians to run at 125mph? I don't recall any resignalling schemes on the MML beyond a few extra banner repeaters as the Meridians could still stop from 125mph in the same distance compared to previous trains with poorer brakes from lower speeds.

Could Class 745s stop from 110mph compared to Class 90s at 100mph in the same distance I wonder?

745 braking is far superior to anything I've driven and most definitely miles better than a 90/DVT. 110mph running would face all the AHB issues on the route, the main reason it has been discounted in the past. Also you cannot compare the GEML with other routes due to the volume of traffic on a mainly double track railway. Once you are south of Shenfield where it quadruples chuck in the Southends and whatever you gain you'll lose around Stratford. Makes no sense to aim for anything higher.

 

[Railperf]

745 braking is far superior to anything I've driven and most definitely miles better than a 90/DVT. 110mph running would face all the AHB issues on the route, the main reason it has been discounted in the past. Also you cannot compare the GEML with other routes due to the volume of traffic on a mainly double track railway. Once you are south of Shenfield where it quadruples chuck in the Southends and whatever you gain you'll lose around Stratford. Makes no sense to aim for anything higher.

As a passenger - and i've been aboard some hard driven 90's (sadly not one of DK1's) and i can vouch for the comments on braking. It's the 745's on/off response that is also very sharp. With the 90's there was clearly a lag from brake controller being moved to brakes kicking in or releasing. The Stadlers seem to offer very responsive and precise braking.

Going back to comments about the 321's, usually your commuter stock used on intense stopping diagrams requires better acceleration and braking than the intercity stock. On a line like the GEML, probably Class 47 levels of acceleration and maximum speeds of 80mph are just about perfect - when you have several stoppers no more than a few minutes ahead.
So now we have the reverse - intercity stock that accelerates faster than all the commuter stuff - mainly 321's - but even the 360's now seem pedestrian in comparison. In fact a 755/4 on diesel is as quick as a Desiro - never mind electric!

 

[jopsuk]

Surely should hardly be a surprise that an EMU with (modern version of) Electro Pneumatic brakes has a rather faster brake response than a loco hauled train with just air brakes?

(and wasn't one of the HST design parameters that they could stop from 125mph in the same distance that a 100mph loco hauled (no DVT) train of similar length could? Partly achieved by having an electrical connection between brake controllers in each power car so the brakes could be applied from both ends simultaneously)

 

[Bald Rick]

Is signal spacing the issue it used to be? How was it solved on the MML for Meridians to run at 125mph? I don't recall any resignalling schemes on the MML beyond a few extra banner repeaters as the Meridians could still stop from 125mph in the same distance compared to previous trains with poorer brakes from lower speeds.

It’s not just signal spacing but signal sighting too. Banners are there to help with the latter, not the former.

On the MML signal spacing was ‘resolved’ in some places with the application of double red aspect sequences. Approaching Radlett Junction is one example, there are many others.

 

[Railperf]

It’s not just signal spacing but signal sighting too. Banners are there to help with the latter, not the former.

On the MML signal spacing was ‘resolved’ in some places with the application of double red aspect sequences. Approaching Radlett Junction is one example, there are many others.

It is a shame that drivers have a DAS system that can tell them where they are and advise power / maximum speeds etc, but that cannot access the signalling data and give drivers a minimum of the next two signal aspects ahead. As passengers we can view the limited open signalling data. Why aren't drivers equipped with this data?

 

[Railperf]

Net running time from Diss to Norwich is 17 minutes. Plus a compulsory [2] minutes recovery time in all schedules.

There is a total of 6 minutes recovery time between Liverpool St and Norwich in all schedules. Network Rail would be reluctant to reduce that, even though it is relatively high compared to other routes for a 115 mile journey, without a wholesale recalculation of the performance metrics. Big money could swing on any changes.

It doesn't help that some of the sectional running times are so slack that the DAS leaving Kelvedon towards Witham advises a maximum of 55mph on 100mph track - absolutely ridiculous!!

 

[Mordac]

It is a shame that drivers have a DAS system that can tell them where they are and advise power / maximum speeds etc, but that cannot access the signalling data and give drivers a minimum of the next two signal aspects ahead. As passengers we can view the limited open signalling data. Why aren't drivers equipped with this data?

That's called CDAS and has been mooted for introduction for ages, but hasn't actually been implemented anywhere in the UK AFAIK.

 

[delticdave]

Surely should hardly be a surprise that an EMU with (modern version of) Electro Pneumatic brakes has a rather faster brake response than a loco hauled train with just air brakes?

(and wasn't one of the HST design parameters that they could stop from 125mph in the same distance that a 100mph loco hauled (no DVT) train of similar length could? Partly achieved by having an electrical connection between brake controllers in each power car so the brakes could be applied from both ends simultaneously)

It's a real pity that there isn't a"like" button on this forum....

Cheers, DC.

 

[delticdave]

As a passenger - and i've been aboard some hard driven 90's (sadly not one of DK1's) and i can vouch for the comments on braking. It's the 745's on/off response that is also very sharp. With the 90's there was clearly a lag from brake controller being moved to brakes kicking in or releasing. The Stadlers seem to offer very responsive and precise braking.

Going back to comments about the 321's, usually your commuter stock used on intense stopping diagrams requires better acceleration and braking than the intercity stock. On a line like the GEML, probably Class 47 levels of acceleration and maximum speeds of 80mph are just about perfect - when you have several stoppers no more than a few minutes ahead.
So now we have the reverse - intercity stock that accelerates faster than all the commuter stuff - mainly 321's - but even the 360's now seem pedestrian in comparison. In fact a 755/4 on diesel is as quick as a Desiro - never mind electric!

A 360/1 has 2000 kW spread over 8 driving axles, & weighs 168 tonnes, a 755/4 on diesel produces 1920 kW, minus the generator / control system & eth losses. It weighs 156.4 tonnes & has only 4 driving axles. I'm sure it's the quicker unit as an emu, but as a dmu I'd like proof. Perhaps you could organise a race, if a suitable railway drag-strip could be made available............

 

[Railperf]

Surely should hardly be a surprise that an EMU with (modern version of) Electro Pneumatic brakes has a rather faster brake response than a loco hauled train with just air brakes?

(and wasn't one of the HST design parameters that they could stop from 125mph in the same distance that a 100mph loco hauled (no DVT) train of similar length could? Partly achieved by having an electrical connection between brake controllers in each power car so the brakes could be applied from both ends simultaneously)

Those who don't understand the engineering might well be surprised that a modern 100mph EMU has more responsive brakes than an HST or 110mph loco hauled stock.
And whether it is a surprise or not is irrelevant. There was a time when i guess it was expected that the Anglia Intercity fleet were to be replaced with an AC version of the Class 444. As much as I do like the Desiro platform - the Stadlers are a superior product. Never before have inexperienced any train able to keep to the line speed profile so closely from an acceleration and braking point of view.
We wait to see how the 720's compare!!

 

[Bald Rick]

It is a shame that drivers have a DAS system that can tell them where they are and advise power / maximum speeds etc, but that cannot access the signalling data and give drivers a minimum of the next two signal aspects ahead. As passengers we can view the limited open signalling data. Why aren't drivers equipped with this data?

Because the signalling data that can be accessed publicly is not 100% reliable.

There is a system where drivers can see more than the next two block sections ahead, it’s called ETCS, and that does away with signal spacing and sighting issues. It doesn’t solve the issue of most of the GEML being built on geology that resembles a sponge, though.

 

[Railperf]

A 360/1 has 2000 kW spread over 8 driving axles, & weighs 168 tonnes, a 755/4 on diesel produces 1920 kW, minus the generator / control system & eth losses. It weighs 156.4 tonnes & has only 4 driving axles. I'm sure it's the quicker unit as an emu, but as a dmu I'd like proof. Perhaps you could organise a race, if a suitable railway drag-strip could be made available............

Don't need that. With a little help from a very friendly driver - who assured me he was applying full power in his 360 - I recorded 0-60mph in 48.9s in 0,5 miles, and 0-95mph in 2min4.9secs and 2.16 miles on level track
On a different stretch of track, slightly downhill - then slightly uphill and a short level stretch - and no OLE voltage values to worry about, I recorded a 755/4 in diesel model achieving 0-60mph in 49.3 secs and 0.45 miles, and 95mph in 2 mins 1 sec at 2.05 miles.

There is absolutely nothing in it as far as I am concerned. The 755/4's in diesel are phenomenal and quicker than a 2+4 HST!!

The driver of the 360- also drives both variants of 755. Until the 755's are cleared south of Colchester, we will not be able to repeat the same acceleration test from the same station on the same piece of track. But here's hoping it might happen one day!

 

[Bletchleyite]

There is absolutely nothing in it as far as I am concerned. The 755/4's in diesel are phenomenal and quicker than a 2+4 HST!!

It does help somewhat (ignoring the HST) that with electric transmission they are not wasting energy heating up hydraulic fluid as any ex-BR DMU (plus classes 170, 175, 180 and 185) does - it all goes down to the rail.

Regear the HST and it'd probably win, though.

 

[Railperf]

Because the signalling data that can be accessed publicly is not 100% reliable.

There is a system where drivers can see more than the next two block sections ahead, it’s called ETCS, and that does away with signal spacing and sighting issues. It doesn’t solve the issue of most of the GEML being built on geology that resembles a sponge, though.

Surely NR can feed 'reliable' internal data to a DAS style system to aid the driver - without the need for the expensive and complex train safety control system that ETCS delivers?

 

[Railperf]

It does help somewhat (ignoring the HST) that with electric transmission they are not wasting energy heating up hydraulic fluid as any ex-BR DMU (plus classes 170, 175, 180 and 185) does - it all goes down to the rail.

Regear the HST and it'd probably win, though.

Real drivers will tell you that the acceleration rate of any Stadler except the 755/3 on diesel is so strong at 95mph that it is believed they would all easily achieve 125mph without regearing - in effect they are software limited to 100mph.
One of the problems the HST has - is that starting off - you have to wait for the train brakes to release - and then due to the ancient traction electronics - you cannot bash it straight into full power (notch 5) without risking some sort of overload. By that time, the Stadler will be sailing off into the distance!
The same applies to 2+5 and 2+6 HST's compared to Class 222's. The power to weight ratio's are similar - but the modern DMU's brakes release and the traction system seems able to deliver full power much quicker to the motors. Plus you probably have more efficient AC traction systems on these too - whereas the HST still uses older DC traction motors.

 

[Railperf]

It does help somewhat (ignoring the HST) that with electric transmission they are not wasting energy heating up hydraulic fluid as any ex-BR DMU (plus classes 170, 175, 180 and 185) does - it all goes down to the rail.

Regear the HST and it'd probably win, though.

Comparing the hydraulic and electric transmissions - say Class 180 vs 22x, similar power to weight ratios etc - the electric transmission does seem more efficient and faster - despite the 22x series having downrated engine outputs.
The heavyweight Siemens Class 185's are more likely to be lower geared but nowadays their 0-100mph acceleration seems on a par if not slightly faster than the downrated 22x's.

 

[Bald Rick]

Surely NR can feed 'reliable' internal data to a DAS style system to aid the driver - without the need for the expensive and complex train safety control system that ETCS delivers?

You’ve just described ETCS though. To feed reliable data to the train needs a secure and high safety intergrity connection to the interlocking, and a secure high safety integrity radio transmission to the train. Those are the key ‘shore’ based components of ETCS, ie the Radio Block Centre and GSM-R. After that it’s all on the train.

Even then, even with a connected DAS, drivers must always obey signals.

 

[Railperf]

You’ve just described ETCS though. To feed reliable data to the train needs a secure and high safety intergrity connection to the interlocking, and a secure high safety integrity radio transmission to the train. Those are the key ‘shore’ based components of ETCS, ie the Radio Block Centre and GSM-R. After that it’s all on the train.

Even then, even with a connected DAS, drivers must always obey signals.

It may sound similar to ETCS, but it doesn't require track balises, train pickup equipment and integration with the train's braking system to start intervening in emergency situations. The data would just sent via GSM-R to the app - and that is it!
Are 745's ETCS ready?

 

[MisterT]

Technically it is possible to have the signalling data delivered at the driver without ETCS. We've done exactly that for years now in The Netherlands, and even when driving with ETCS it gives a lot more information, as it displays not only the data from your train and its MA, but also on the trains ahead of you, like their position and their planned or already authorised path. For example:



My train (the blue line) is driving a bit before station Ot (Oisterwijk), and in front of me is an early running freight train, just before Tb (Tilburg station), which has a path set into the station, platform 2. In front of that, a local stopping service is leaving my planned path (the block with the arrow), and there's another local stopping service (1 minute late atm) way ahead.

 

[Bald Rick]

It may sound similar to ETCS, but it doesn't require track balises, train pickup equipment and integration with the train's braking system to start intervening in emergency situations. The data would just sent via GSM-R to the app - and that is it!
Are 745's ETCS ready?

745s should be ETCS ready but I don’t know if they are.

Balinese and the train pick up equipment are really rather cheap. The expensive bit is all the clever stuff on the train, the RBC, the data, the design, and the entry into service.