GWR Class 800

[hexagon789]

Im not so sure that the Diesel running is fully understood. Obviously a 800 running on Diesel will be out accelerated by an HST but i think that will only be so where there are high speed limits. I can see a situation where running speeds are relatively low where the 800s modern electric traction package and distribution will be able to put more power out at the wheels than a HST resulting in a faster journey time. I can certainly see that being so at places like the Devon Banks and Main line in Cornwall, and I can well imagine that overall an 800 will be as good as or better than an HST overall on the through journey between Paddington and Penzance

It's been said that an 800 in Diesel-mode out accelerates an HST to 30 mph, an HST catches it up by 60 mph and out-accelerates it above 60. Even including the superior electric performance between Paddington and Didcot, I don't see an 800 out doing a '125' to Penzance, at least not until the 'live' wires run out further.

 

[hexagon789]

I have had three IETs on separate runs reach 123/124 mph between Bristol Parkway and Didcot, a stretch on which they are still running entirely on diesel.

I don't doubt it, but that's not entirely level. On dead level track they balance at about 118 and going up the 1-in-754 gradient from Didcot to Swindon speed drops off to about 112 on full power. Going from Didcot to Swindon though they seem to be able to nudge 123-124 mph.

 

[Peter Mugridge]

I should have mentioned that I have recorded that speed in both directions on that stretch.

 

[hexagon789]

I should have mentioned that I have recorded that speed in both directions on that stretch.

Fair enough, but we can perhaps agree at least that they are much poorer on Diesel in general.

 

[Peter Mugridge]

Yes, that much is true. Then again, as many have said - they weren't designed to do 125mph on diesel were they? They seem to be OK at the slower speeds they were intended to use that mode in. We can of course only analyse this properly once the electrification works are finally completed.

 

[Railperf]

Definitely - but the Class 91's performance isn't something to sniff at. The don't take off like a rocket like the 387s/800s do (when the driver wants to/can) but they get up to speed deceptively quickly. I've gone over Colton Junction south from a standing start at York at over 110mph in a mk4/91 many a time - a distance of about 5 1/2 miles. An HST is a little more leisurely, crossing just over 100mph from personal experience. I think the factoid about the HST is that it takes 11 miles to reach 125? 5.5 miles for the first 100, and 5.5 for the last 25.....

Based on real and accurate GPS recordings using professional equipment, these are the results of a virtual drag race over 9 miles. You can make up your own minds about which is superior:-
HST 2+8 set: 6 min 33 sec - 119mph
Class 91 & Mk 4 consist: 6 min 25 sec - 125mph
2 x 5-Car Class 800 IET Diesel: 6 min 59 sec - 107mph
Class 180 5-car: 6 min 6sec - 121mph (driver had eased off and was cruising)
2 x 5-car Class 800 IET Electric - 5 min 38 sec - 124mph (causing speed)

 

[hexagon789]

Based on real and accurate GPS recordings using professional equipment, these are the results of a virtual drag race over 9 miles. You can make up your own minds about which is superior:-
HST 2+8 set: 6 min 33 sec - 119mph
Class 91 & Mk 4 consist: 6 min 25 sec - 125mph
2 x 5-Car Class 800 IET Diesel: 6 min 59 sec - 107mph
Class 180 5-car: 6 min 6sec - 121mph (driver had eased off and was cruising)
2 x 5-car Class 800 IET Electric - 5 min 38 sec - 124mph (causing speed)

Am I allowed to say an HST as they are my favourite train, or is that pushing things a bit?

 

[najaB]

Based on real and accurate GPS recordings using professional equipment, these are the results of a virtual drag race over 9 miles. You can make up your own minds about which is superior:-
HST 2+8 set: 6 min 33 sec - 119mph
Class 91 & Mk 4 consist: 6 min 25 sec - 125mph
2 x 5-Car Class 800 IET Diesel: 6 min 59 sec - 107mph
Class 180 5-car: 6 min 6sec - 121mph (driver had eased off and was cruising)
2 x 5-car Class 800 IET Electric - 5 min 38 sec - 124mph (causing speed)

Where was this, since you're comparing runs I assume it was over the same track in the same conditions?

 

[Railperf]

They are undoubtedly better on electric mode, it just that with so much Diesel running now, it seems they will struggle to maintain schedules - this has of course been discussed at length anyway.

It will be interesting to see how the Electric only IEPs, which will be lighter I assume, will fair.

They may be lighter, but will still be limited to the DfT defined acceleration curve, which the heavier bi-modes already achieve in electric mode despite the extra weight.
In essence, without any kind of acceleration control, an electric only IEP could likely accelerate very fast indeed.

 

[Railperf]

Where was this, since you're comparing runs I assume it was over the same track in the same conditions?

Yes - otherwise it would be a pointless comparison. The Class 91 / Mk4 timings are taken from a good location on the ECML - reasonably level start, good conditions etc - as they have never visited GWML metals as far as I know - unless GWR want to lease one in for a day .

 

[Bornin1980s]

I'm okay with slightly lower top speeds. After all, I'm sure they are faster than the old GWR steam trains.

It is only a problem if the timetable doesn't take the lower performance into account. Are these trains given timetables they can't keep?

 

[Railperf]

I'm okay with slightly lower top speeds. After all, I'm sure they are faster than the old GWR steam trains.

It is only a problem if the timetable doesn't take the lower performance into account. Are these trains given timetables they can't keep?

Class 800's have been introduced on existing HST schedules. In electric mode they perform better than HST's and easily meet the schedule. Where they are used in diesel mode on the high-speed sections - they struggle to meet the timings.
On lower speed stretches of track into South Wales and on the Cotswolds - the 800's appear to to meet the current schedules okay. It will be interesting to see how the December 2018 timetable is tweaked to take into account the superior electric performance, and to reflect the slightly lower diesel performance.

 

[Railperf]

I'm okay with slightly lower top speeds. After all, I'm sure they are faster than the old GWR steam trains.

In the early days of HST's speed made such a difference, because the trains had far fewer stops and could run at their 125mph top speed for longer. Today, the Bristol service is virtually an all stations stopping service , with stops every 10 to 20 minutes. So the ability to run for long distances at a sustained high-speed is lost.
Therefore the acceleration and braking performance takes centre stage, minimising time lost at station stops. HST's are allowed 24 minutes net from Paddington to Reading. The lower speed restrictions out of Paddington mean that 22.5 to 23 minutes represents the fastest that this journey can be achieved in an HST running at 125mph without an delays or time dissipation.
yet, you could theoretically achieve a 23.5 minute journey time using a 100mph Desiro, just by changing the speed limit profile out of Paddington and allowing the Desiro to accelerate to full speed as soon as the rear car has passed the end of the station platform.
That's food for thought! probably on the longer sections such as Reading to Swindon - higher speeds are needed.

Therefore I stand by my thinking that an electric Desiro running at only 110mph would easily achieve the current timetable -if the OLE equipment was there to run under!
For all the criticism of the East Coast wiring, it has done a pretty good job and a slightly tweaked version should have allowed far more of the GWML to have been electrified at a far lower cost.

 

[jimm]

Class 800's have been introduced on existing HST schedules. In electric mode they perform better than HST's and easily meet the schedule. Where they are used in diesel mode on the high-speed sections - they struggle to meet the timings.

Which you know full well is hardly a surprise, as they were never expected to have to run for long distances on diesel on 125mph sections - and won't be doing it bar a short section on the Bath route after all of 14-and-a-bit months come next January. Is there some reason you are still going on about it as though it is some fatal flaw?

On lower speed stretches of track into South Wales and on the Cotswolds - the 800's appear to to meet the current schedules okay. It will be interesting to see how the December 2018 timetable is tweaked to take into account the superior electric performance, and to reflect the slightly lower diesel performance.

I have pointed out previously that 800s are more than meeting current schedules on the Cotswold Line, regularly taking minutes out of booked timings, thanks to the fast acceleration before another stop just seven or eight minutes away - and reduced station dwell times thanks to the power doors are also helping. Someone I know has been timing station stops when using 800s on the Cotswold Line and says the average is in the 60-75 seconds range - which is ever so slightly faster than what happens with HSTs when train managers walk the length of the platform - and some of them all the way back again - to check that the slam doors are shut.

GWR and Network Rail are apparently working on new sectional running times at the moment to finalise the draft timetable for next January but I fully expect GWR to deliver the promised fastest journey time between London and Worcester of two hours, with other services taking five to 10 minutes more, depending on calling patterns.

In the early days of HST's speed made such a difference, because the trains had far fewer stops and could run at their 125mph top speed for longer. Today, the Bristol service is virtually an all stations stopping service , with stops every 10 to 20 minutes. So the ability to run for long distances at a sustained high-speed is lost.

Apart from all the extra Bristol off-peak services (and I think the third South Wales service each hour in the peaks) that will be introduced next January and will, er, run non-stop for long distances at sustained high speed between Paddington and Bristol Parkway.

For all the criticism of the East Coast wiring, it has done a pretty good job and a slightly tweaked version should have allowed far more of the GWML to have been electrified at a far lower cost.

Try telling that to anyone who has lost hours of their life stuck on the ECML whenever the overhead has fallen down...

 

[najaB]

Yes - otherwise it would be a pointless comparison.

So the Class 91 timings are pointless (since they weren't on the same track). And were the others all flat out speed runs on the same stretch of track in the same conditions?

 

[Envoy]

800009 has been named ‘John Charles’ - and I think that 800004 has been named ‘Sir Gareth Edwards’.
http://www.juventus.com/en/news/news/2018/john-charles-honoured-by-great-western-railway.php

Great Western Railway have today honoured Juventus legend John Charles by naming train number 009 of their new Class 800 (800009) Intercity Express Train after the three-time Scudetto winner. The family of the former Juventus and Wales footballer, as well as Juventus Museum President Paolo Garimberti were in attendance to welcome the newly crowned train onto the platform at London Paddington station.

 

[Domh245]

800009 has been named ‘John Charles’ - and I think that 800004 has been named ‘Sir Gareth Edwards’.
http://www.juventus.com/en/news/news/2018/john-charles-honoured-by-great-western-railway.php

Same train I believe. They are continuing the 'tradition' they've set of each unit having two names (eg 800004 is Ismbard Kingdom Brunel on one end, and Sir Daniel Gooch on the other)

 

[bastien]

Which you know full well is hardly a surprise, as they were never expected to have to run for long distances on diesel on 125mph sections - and won't be doing it bar a short section on the Bath route after all of 14-and-a-bit months come next January. Is there some reason you are still going on about it as though it is some fatal flaw?



I have pointed out previously that 800s are more than meeting current schedules on the Cotswold Line, regularly taking minutes out of booked timings, thanks to the fast acceleration before another stop just seven or eight minutes away - and reduced station dwell times thanks to the power doors are also helping. Someone I know has been timing station stops when using 800s on the Cotswold Line and says the average is in the 60-75 seconds range - which is ever so slightly faster than what happens with HSTs when train managers walk the length of the platform - and some of them all the way back again - to check that the slam doors are shut.

GWR and Network Rail are apparently working on new sectional running times at the moment to finalise the draft timetable for next January but I fully expect GWR to deliver the promised fastest journey time between London and Worcester of two hours, with other services taking five to 10 minutes more, depending on calling patterns.



Apart from all the extra Bristol off-peak services (and I think the third South Wales service each hour in the peaks) that will be introduced next January and will, er, run non-stop for long distances at sustained high speed between Paddington and Bristol Parkway.



Try telling that to anyone who has lost hours of their life stuck on the ECML whenever the overhead has fallen down...

I think you're missing the point, Jimm. That point being - the entire IEP project is there to satisfy the arbitrary expectations of Some Guy With A GPS Recorder.

 

[Railperf]

I think you're missing the point, Jimm. That point being - the entire IEP project is there to satisfy the arbitrary expectations of Some Guy With A GPS Recorder.

But of course it is

 

[Railperf]

It's been said that an 800 in Diesel-mode out accelerates an HST to 30 mph, an HST catches it up by 60 mph and out-accelerates it above 60. Even including the superior electric performance between Paddington and Didcot, I don't see an 800 out doing a '125' to Penzance, at least not until the 'live' wires run out further.

Let us see how GWR / Hitachi configure the power outputs of 'their' 802's. Will it be 940hp reducing to 750hp in the mid and upper speed ranges a la 800's? Or will we get all 940 horses available across the entire speed range? That will determine whether the timings to Penzance can be reduced.

 

[reddragon]

Ah, so 190 of the horses in the 800s are slow horses unable to canter or run, just walk or trot and Hitachi are going to teach all 940 horses in the 802s to run fast!

 

[Dai Corner]

Ah, so 190 of the horses in the 800s are slow horses unable to canter or run, just walk or trot and Hitachi are going to teach all 940 horses in the 802s to run fast!

Haha Absolutely brilliant analogy!

 

[Railperf]

Horses need fuel to carry on running...so if Hitachi can keep the food and water flowing..all 940 hordes will carry on pulling. Apparently they dont want to wear the horses out, and keep them all going for a few more races lol.

 

[reddragon]

Haha yes and the 801 has donkeys in it only engine

 

[D1009]

Let us see how GWR / Hitachi configure the power outputs of 'their' 802's. Will it be 940hp reducing to 750hp in the mid and upper speed ranges a la 800's? Or will we get all 940 horses available across the entire speed range? That will determine whether the timings to Penzance can be reduced.

Earlier in this thread I asked whether the 800s would be able to work in miltiple with the 802s and was told yes. I would have thought this difficult if the power outputs are configured differently.

 

[D365]

I would have thought this difficult if the power outputs are configured differently.

I'd imagine the TMS would be clever enough to deal with this accordingly.

 

[Railperf]

Not really ... two 800 sets happily couple together - even if one set has one, two or all three engines out.

 

[Railperf]

Also recall that a Class 91 and HST power car happily worked together either end of a mark 3 consist as a hybrid pairing - even though the class 91 was producing 6300hp with the HST power car producing only 1770hp at the rail. There is no major strain on the train..the more powerful loco / set has less of a load as the contributing loco assists it
The assisting or less powerful loco had an easier task than if it were hauling propelling a dead load.

 

[themiller]

Earlier in this thread I asked whether the 800s would be able to work in miltiple with the 802s and was told yes. I would have thought this difficult if the power outputs are configured differently.

Can't see a problem as BR designed 158s regularly work with Leyland designed 153s on the S&C. Systems have moved on a bit since then so I would suspect that Hitachi have ensured that they're cleverer, now.

 

[D1009]

Not really ... two 800 sets happily couple together - even if one set has one, two or all three engines out.

OK, so technically no problem.

However, the reason the 802s were specified with the full 940 hp available was to cope with the gradients in Devon and Cornwall. These are comparitively low speed sections, so if the 800s are already delivering this in the low speed ranges, why should the 802s be configured any differently? Presumably the issues involving maintenance of the engines will be the same, even if someone else is paying.