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GWR Class 800

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bastien

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That's not a great or particularly relevant analogy.

I'm sure some drivers of 155mph capable cars (brand is irrelevant) would travel at 155mph if it was safe and legal, but it isn't, so they don't.

The IET is a new train replacing a 40 year old one, and it struggles to match the performance on diesel. Not Hitachis fault, just badly specified.

I'm struggling to see how the analogy works.

You're going with option B from the analogy, then.
 
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Dai Corner

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Let's try another motoring analogy.

I'm meeting friends for lunch at 1300 and know from previous experience that if I drive at a steady 60-65 I will get there in time. I could make full use of my cars ability to do 0-60 in 8s and cruise at 70-80 as any police around will not stop me for doing that.

Should I save fuel and wear and tear on my car or have some fun?
 

bastien

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Let's try another motoring analogy.

I'm meeting friends for lunch at 1300 and know from previous experience that if I drive at a steady 60-65 I will get there in time. I could make full use of my cars ability to do 0-60 in 8s and cruise at 70-80 as any police around will not stop me for doing that.

Should I save fuel and wear and tear on my car or have some fun?

That would rather depend on whether you have someone in the back seat nagging you to go faster, because you used to go faster in your old car.

(Oh, and if you don't go fast they'll post a GPS trace from their phone - that proves how embarrassingly slow your new car is - on the internet. So there!)
 

Dai Corner

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That would rather depend on whether you have someone in the back seat nagging you to go faster, because you used to go faster in your old car.

(Oh, and if you don't go fast they'll post a GPS trace from their phone - that proves how embarrassingly slow your new car is - on the internet. So there!)

What if my passenger gave me money towards the petrol and found it was less than last time in my old car as I was driving more economically?

Or to put it another way I told him I'd go faster if he gave me a fiver?
 
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Domh245

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Not Hitachis fault, just badly specified.

I'd disagree with that. When procured, they weren't supposed to need 125mph capability away from the wires. The fact that they still seem to take an age to reach 100mph, which is the most that might have been reasonably expected to do away from the wires, is a different matter.

I note that @Railperf's post talks about not keeping up with the performance of an HST, and notes that the HST builds up a 12 second lead "within a few miles" but doesn't talk about point to point timing. Maybe I'm being overly cynical and reading too much into it, but from what has not been written in that post, can we take it that the point to point timings are negligible, or at least within the resolution of the timetable? Or are the IETs utilising their superior dwell time (assuming that's been rectified compared to the earliest runs?) to keep to the timetable - if they are at all.
 

Master29

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So why does this have to be repeated again and again, that they have not been set to max possible performance throughout the range, and frankly who cares if they struggle to quite get to 125mph on Diesel because that was not required in the specification, but the fact they can get to near 125mph and get Network Rail out of mire is quite impressive in my view.

Well quite a few people care actually; that a new train is slower than the 42 year old it`s replacing. It may not have been required by the Daft but it shows the whole fiasco from the start. Not necessarily a bad train just typical British nimcompoopary.
 

D1009

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I'd disagree with that. When procured, they weren't supposed to need 125mph capability away from the wires. The fact that they still seem to take an age to reach 100mph, which is the most that might have been reasonably expected to do away from the wires, is a different matter.

I note that @Railperf's post talks about not keeping up with the performance of an HST, and notes that the HST builds up a 12 second lead "within a few miles" but doesn't talk about point to point timing. Maybe I'm being overly cynical and reading too much into it, but from what has not been written in that post, can we take it that the point to point timings are negligible, or at least within the resolution of the timetable? Or are the IETs utilising their superior dwell time (assuming that's been rectified compared to the earliest runs?) to keep to the timetable - if they are at all.
I totally agree. Railperf's posts seem to be based on every new form of traction needs to be faster than what it replaced. This used to be the case when the railway was going out of its way to attract people out of their cars. These days people are not using their cars as much, some are abandoning them completely as the road system becomes more congested, and as a result the railway simply can't cope with the numbers. So can we please agree that the IETs don't go as fast on diesel as the HSTs and were never intended to.
 

Dai Corner

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I'd disagree with that. When procured, they weren't supposed to need 125mph capability away from the wires. The fact that they still seem to take an age to reach 100mph, which is the most that might have been reasonably expected to do away from the wires, is a different matter.

I note that @Railperf's post talks about not keeping up with the performance of an HST, and notes that the HST builds up a 12 second lead "within a few miles" but doesn't talk about point to point timing. Maybe I'm being overly cynical and reading too much into it, but from what has not been written in that post, can we take it that the point to point timings are negligible, or at least within the resolution of the timetable? Or are the IETs utilising their superior dwell time (assuming that's been rectified compared to the earliest runs?) to keep to the timetable - if they are at all.

Yes, as I think I've said before in this thread, it's keeping to the timetable that matters to the operators and passengers. If it is found the IETs aren't meeting punctuality targets a decision can be made as to whether it's worth paying for higher acceleration in diesel.
 

ash39

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Let's try another motoring analogy.

I'm meeting friends for lunch at 1300 and know from previous experience that if I drive at a steady 60-65 I will get there in time. I could make full use of my cars ability to do 0-60 in 8s and cruise at 70-80 as any police around will not stop me for doing that.

Should I save fuel and wear and tear on my car or have some fun?

That one makes sense.

I understand they are currently just about keeping to HST schedules? Which were fairly generously padded to begin with. The point remains that the newer train which is being heralded as a huge upgrade by the TOC/DFT, still isn't as capable on diesel as the train is supercedes. Whilst I take your point that they are doing what is asked of them currently, the jury is still out on how well they can recover lost time during disruption, or how they perform on steeper gradients.
 

bastien

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What if my passenger gave me money towards the petrol and found it was less than last time in my old car as I was driving more economically?

Or to put it another way I told him I'd go faster if he gave me a fiver?

Well your passenger might decide he can make more than a fiver by selling his "Dai's New Car, Slower Than His Old Car Embarrasment" scoop to the local paper (for shocking graphs, see inside!). And so, here we are.
 

JN114

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That one makes sense.

I understand they are currently just about keeping to HST schedules? Which were fairly generously padded to begin with. The point remains that the newer train which is being heralded as a huge upgrade by the TOC/DFT, still isn't as capable on diesel as the train is supercedes. Whilst I take your point that they are doing what is asked of them currently, the jury is still out on how well they can recover lost time during disruption, or how they perform on steeper gradients.

But the further point is there is plenty of scope to uprate that performance if it is materially found to be lacking. They are not operating at their maximum capability on Diesel. They are operating at a level that allows them - quite successfully from my anecdotal observation - to keep to current schedules. Electrification will then deliver increased performance on core routes and enable journey time savings to be made.
 

Dai Corner

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Well your passenger might decide he can make more than a fiver by selling his "Dai's New Car, Slower Than His Old Car Embarrasment" scoop to the local paper (for shocking graphs, see inside!). And so, here we are.

Stretching the analogy a bit further, the local paper aren't interested in the story, nor are our luncheon companions who are just pleased we got there on time. However my back seat driver writes up the story and sells it to Petrolheads Weekly together with lots of detailed figures and graphs which their readers lap up.
 

Railperf

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There isn't any evidence yet of superior dwell time - especially when a 10-car unit has 5 cars locked out of use, and everyone has to scramble along the platform into the front or rear 5 cars. The jury is out on that at the moment. And will an IET have a superior dwell time to the now departed class 180's which also had power doors?
GWR are actively advertising that Class 800's 'superior' acceleration -in diesel mode - is 'one' of the ways they claim to be able reduce journey times across the network. Just check their Twitter account!!
So far the evidence suggests that the only time savings will only be on sections where the trains run in electric mode only.
All this talk about unmuzzling to a full 700KW misses the point. To provide superior journey times on the diesel sections of the network you need something with Class 180/ Class 220/1/2 power to weight ratio. A 5-car Class 800 weighs about the same as a 5-car 221, but is way down on power even if you have a full 700KW per engine available from 0-125mph! Cue approx 12hp ton for a Voyager compared to 9hp ton for a Class 800!
 

Railperf

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Haha, this analogy is fun! Reminds me when Ferrari claimed their new F50 was faster than the older F40 - but it wasn't!!
 

Railperf

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With regards to dwell time, it will be interesting to see how the 800's will cope with the summer Newquay services. It could take 5 mins plus to try and load all the baggage onto an HST TGS at Reading even with 5 platform staff to hand!!
 

Railperf

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This isn't Dai's new slower car. This is a multimillion pound train -paid for by you and me the taxpayer - that is supposed to improve services to the west of England for millions of travellers that don't want to sit on clogged up motorways or own a car. But so far, the new trains may look fabulous, but they are less comfortable, slower, and when 5 cars are locked out of use - create worse overcrowding than they trains they are supposed to be replacing!
 

Domh245

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There isn't any evidence yet of superior dwell time - especially when a 10-car unit has 5 cars locked out of use, and everyone has to scramble along the platform into the front or rear 5 cars. The jury is out on that at the moment. And will an IET have a superior dwell time to the now departed class 180's which also had power doors?

Interesting. Hopefully it'll be something that sorts itself out after a while. Do you know if the SDO issues that seemed to plague the first month or so of runs are still happening or have they become less frequent. As for the 180, I expect that they'd be similar performers - by my estimation they both have reasonably similar saloon lengths, and the main dwell time saving was always supposed to be from not having to allow time for the guard or platform staff to run around closing doors (although it is to some extent cancelled out by the time taken to unlock and lock the doors, partially as a result of the door sounders)


GWR are actively advertising that Class 800's 'superior' acceleration -in diesel mode - is 'one' of the ways they claim to be able reduce journey times across the network. Just check their Twitter account!!
So far the evidence suggests that the only time savings will only be on sections where the trains run in electric mode only.

I presume that is related to that video of the IET giving it the beans out of a station, composited with an HST giving a slightly less enthusiastic departure? Oddly enough though, scrolling back through their most recent tweets, the first IET one that I find was about the first service to Carmarthen, and the second one (and first reference to fast in the context of IET) which notes that the faster journeys to the Cotswolds only start at the end of 2019!

All this talk about unmuzzling to a full 700KW misses the point. To provide superior journey times on the diesel sections of the network you need something with Class 180/ Class 220/1/2 power to weight ratio. A 5-car Class 800 weighs about the same as a 5-car 221, but is way down on power even if you have a full 700KW per engine available from 0-125mph! Cue approx 12hp ton for a Voyager compared to 9hp ton for a Class 800!

I know what you are saying, although the obvious caveat is that it is power at the rail that you are interested in. You could have a train with a Voyager power:weight ratio, but if you are using 75% of the installed power to power a massive flashing sign saying "Look at me! I'm the most powerful train ... In the world" then it isn't going to perform like a Voyager!
 

Domh245

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But so far, the new trains may look fabulous, but they are less comfortable, slower, and when 5 cars are locked out of use - create worse overcrowding than they trains they are supposed to be replacing!

So to summarise, you've got an issue with something that is subjective (but if blame must be assigned, the DfT), with infrastructure delays causing the trains to be used in ways they shouldn't have (ie NR), and with inadequate numbers of trained crew (GWR). These are the fault of the train how exactly?
 

JN114

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Comfort is entirely subjective. I much prefer the new trains to HSTs for comfort in all classes; but I’m quite happy to concede that my tastes may not match others.

I’ve heard many fables about luggage on high summer Cornish trains. I’ve never actually witnessed any of the extravagant scenes that are often described - despite actively making an effort to go to Paddington, Reading, Plymouth to witness the issues first hand. The trains were busy; with luggage in aisles and luggage racks overflowing. But I never saw the supposed armies of platform staff loading the TGS to bursting point. Perhaps there has been a decline in patronage? Perhaps people are now taking a sensible amount of luggage with them. Or perhaps these stories are just exaggerated every time they’re recounted. New trains have plenty of full size luggage racks at coach ends; larger overhead luggage provision and lockable luggage stores in certain vehicles. I surmise the capacity is around the same if not better - it’s just spread out throughout the train than all in one vehicle. Much like when they did away with separate luggage carriages and put smaller van accommodations within the passenger formation of the train.

10 with 5 locked out is a temporary staffing issue. At some point in the not too distant future one side or the other is going to blink; and it will get resolved permanently. I have no opinion on how they do it - I like many of my ops colleagues just want to run 10 car trains.
 

Dai Corner

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As I've remarked before, I think the faster journey times will be achieved largely through timetable and service pattern changes, with reduced dwell times and superior performance under the wires compared with HSTs also contributing. Remember that HSTs did Paddington - Temple Meads in 87 mins with two stops at one time.

In my motoring analogy, I could have got there more quickly by not stopping to pick up my passenger.
 

bastien

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All this talk about unmuzzling to a full 700KW misses the point. To provide superior journey times on the diesel sections of the network you need something with Class 180/ Class 220/1/2 power to weight ratio. A 5-car Class 800 weighs about the same as a 5-car 221, but is way down on power even if you have a full 700KW per engine available from 0-125mph! Cue approx 12hp ton for a Voyager compared to 9hp ton for a Class 800!

This is where I have a problem with what you're doing: You have this conclusion, already written.

Then you have some incomplete data - how 800s are being driven today (ie. not how hard they could be driven, or how they'll be operated in future).

Of course, this data supports the conclusion... Type it up and hand it in!

This is the point where a science undergraduate has a nice chat with their tutor and head of department, about whether or not they're still on the course.
 

coppercapped

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This isn't Dai's new slower car. This is a multimillion pound train -paid for by you and me the taxpayer - SNIPPED!
Wrong. None of the trains procured under the IEP contract have been paid for by the taxpayer - as has been written many times before by many contributors, Hitachi has funded the entire programme. The DfT spent some several tens of millions on consultancy during the specification and contract negotiation phases, but this stopped when the contracts were signed.

To be fair, it has not yet been published which organisation carries the costs for the uprating of the IEP batch of trains, so this may well end up with the taxpayer but in comparison with the other costs it will be very small.
 

59CosG95

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In other news, 800010's just been named at Paddington; it now carries "Michael Bond" on one end, and "Paddington Bear" on the other. Each door now has a transfer of the aforementioned bear as well.
 

jimm

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Getting back to performance in diesel mode...the Cotswold trips are starting to highlight a lack of installed power too. Despite a mere 75mph speed limit, IET's struggle to accelerate on steep grades and cannot keep up with HST's performance on that line either. I've seen data that shows how an IET streaks away from a station stop to gain a 25 second advantage, but over 45mph on a rising 1 in 100 gradient cannot accelerate quickly enough to linespeed. Eventually overtaken by the HST which then establishes a 12 second lead within a few miles of the station start. These units really are toothless in Diesel mode unless linespeeds are no more than 50 or 60mph!! That's progress!

Two points about the Cotswold Line:

a. The stations are pretty much "a few miles apart" - seven miles being about the average, so what does it matter if an HST is going like a bat out of hell by then, when there's actually a station stop to make? And an initial burst of acceleration is quite handy when there are frequent stops and starts.

b. There is precisely one section of 1 in 100 in the just under 60 miles between Oxford and Worcester - the four miles of Chipping Campden bank - where even an HST in good form and on dry rails will rarely top 70mph, never mind hit the 75mph limit - a limit that only applies between Moreton-in-Marsh and Evesham, the rest of the line is in the 90-100mph range, bar the curve at Shipton, which is also 75mph

Yes, a couple of minutes have been added to IET timings between Evesham and Moreton-in-Marsh to allow for the climb, but yesterday's 0954 from Malvern - started from Worcester due to signal problems in London affecting its outbound run - ended up going quite nicely on the downhill leg from Moreton-in-Marsh and reached Oxford two minutes early at 11.27, the arrival time of the 180 service up until Christmas, suggesting it was going quite well on diesel at speeds a tad above 60mph... It then ran early pretty much the entire way from Oxford to Paddington, even in puny diesel mode as far as Didcot.

I really am struggling to understand exactly what it is that you are trying to prove with this contribution and all the previous stuff about running at 100mph+ speeds on diesel, when that effectively becomes a non-issue in 12 months' time.
 
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47802

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Well quite a few people care actually; that a new train is slower than the 42 year old it`s replacing. It may not have been required by the Daft but it shows the whole fiasco from the start. Not necessarily a bad train just typical British nimcompoopary.

Do they why is that?, the point is yet again they designed to run on Electric on the fastest sections of the route where they are quicker, while the Diesel Sections of the route have slower Line speed's, while at the moment due to a lack of wires they are being asked to do something which they were not specified to do, why is that such a difficult concept to grasp? why do we need a 125mph Diesel Train when the Diesel Sections of the route don't have 125mph line speeds?

While in terms of acceleration I don't think it has been proved that non Dft specified 802 with full power available throughout the range will be slower.
 
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JamesRowden

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Acceleration = Power / Speed / Mass - Drag_Coefficient * Speed^2 / Mass (when the train is at a high enough speed to be limited by power rather than tractive effort)

This equation shows that limited power is far more significant on a 125mph line compared to a 75mph line.
 

Master29

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Do they why is that?, the point is yet again they designed to run on Electric on the fastest sections of the route where they are quicker, while the Diesel Sections of the route have slower Line speed's, while at the moment due to a lack of wires they are being asked to do something which they were not specified to do, why is that such a difficult concept to grasp? why do we need a 125mph Diesel Train when the Diesel Sections of the route don't have 125mph line speeds?

While in terms of acceleration I don't think it has been proved that non Dft specified 802 with full power available throughout the range will be slower.


I`m not talking about the slower sections of route where the trains were not designed to run at 125mph. I`m talking about the whole fiasco around the electrification issue. No difficult concept there. Yes things will pick up eventually once electrification (whenever that will be) is complete.
 
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59CosG95

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I`m not talking about the slower sections of route where the trains were not designed to run at 125mph. I`m talking about the whole fiasco around the electrification issue. No difficult concept there. Yes things will pick up eventually once electrification (whenever that will be) is complete.
Not sure when (or if, at the rate things are going) the Cotswold Line'll get wired though; this has been highlighted earlier as one of the "problem areas" for the 800s on diesel. I think someone mentioned on here that the Cotswold Line would be one of the candidates for 802 operation for this very reason, as they've got access to more engine-based power & all that.
 

jimm

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Not sure when (or if, at the rate things are going) the Cotswold Line'll get wired though; this has been highlighted earlier as one of the "problem areas" for the 800s on diesel. I think someone mentioned on here that the Cotswold Line would be one of the candidates for 802 operation for this very reason, as they've got access to more engine-based power & all that.

It was highlighted as a supposed 'problem area' by someone who doesn't seem to know much about the Cotswold Line in the first place, as I pointed out yesterday.

There is nothing so far on realtimetrains suggesting that 800-worked services are struggling to keep to booked times, despite not being able to climb Chipping Campden bank like a space rocket, which I don't think anyone was expecting them to do in the first place. My only trip up the hill so far suggests that 800011 at least can manage it perfectly well, albeit without quite the same sound effects as HSTs or 180s.

The 800s will work most services on the Cotswold Line. 802s are unlikely to be seen much outside the peaks, when the extra capacity of the nine-car sets will be needed.
 
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