GWR Class 800

[coppercapped]

Does anyone know if any line speed changeovers have been completed or due to be undertaken yet?

Yes, many months ago during early testing on the ECML. Information from the Hitachi man responsible for approvals to an IMechE meeting.

 

[coppercapped]

Would I be right in thinking it was those tests which contributed toward the realisation of insufficient power, and the subsequent order of the 802's with higher output?

No, you would be wrong.

 

[spark001uk]

No, you would be wrong.

Ok. It wasn't my personal assumption, I was going by the Wiki article, which mentioned the 802s being more able to deal with the west country gradients, and also having the necessary larger fuel tanks.

 

[D1009]

110 m.p.h. max. Diesel only.

I find that surprising. I know that the data on RTT isn't accurate to the quarter minute, but the times shown on 1X80 today from Reading to Swindon start to stop in 24 minutes, and from Swindon to Bristol Parkway in 23 minutes suggest to me that if it was 110 mph max, the acceleration must have been very impressive.

 

[leomartin125]

I find that surprising. I know that the data on RTT isn't accurate to the quarter minute, but the times shown on 1X80 today from Reading to Swindon start to stop in 24 minutes, and from Swindon to Bristol Parkway in 23 minutes suggest to me that if it was 110 mph max, the acceleration must have been very impressive.

I didn't know the IEP's could reach 110mph on diesel, and I believe today's test run was the timings of an IEP that ran diesel thoughout from Paddington to Parkway and return. I presume once on the juice from Paddington to Didcot, it will be slightly quicker overall?

 

[LNW-GW Joint]

I find that surprising. I know that the data on RTT isn't accurate to the quarter minute, but the times shown on 1X80 today from Reading to Swindon start to stop in 24 minutes, and from Swindon to Bristol Parkway in 23 minutes suggest to me that if it was 110 mph max, the acceleration must have been very impressive.

That's exactly the same as service HST trains today (eg 1B25).

 

[najaB]

That's exactly the same as service HST trains today (eg 1B25).

But with a 110mph maximum speed vs 125mph it's impressive.

 

[asylumxl]

That's exactly the same as service HST trains today (eg 1B25).

Well, if it's running at 110mph rather than 125mph...

 

[Roast Veg]

Don't forget that the acceleration of the HST is significantly lower than the IEP, so through some slower sections the difference in time will be negligible. I haven't studied the sections in question, so this could be irrelevant.

 

[deltic08]

Running via Sapperton is no more challenging than climbing out of the Severn Tunnel or up to Badminton (on diesel, that is, which will apply for at least a year).

Where on the section between STJ and Swindon is the gradient 1 in 60 with continuous reverse curves for 10 miles?

 

[Noddy]

Where on the section between STJ and Swindon is the gradient 1 in 60 with continuous reverse curves for 10 miles?

With a station near the bottom.

 

[LNW-GW Joint]

Where on the section between STJ and Swindon is the gradient 1 in 60 with continuous reverse curves for 10 miles?

With a station near the bottom.

OK I give in.
However unlike Badminton they won't be trying to reach 90+mph uphill via Sapperton (line speed 50/60).

 

[47802]

I didn't know the IEP's could reach 110mph on diesel, and I believe today's test run was the timings of an IEP that ran diesel thoughout from Paddington to Parkway and return. I presume once on the juice from Paddington to Didcot, it will be slightly quicker overall?

At lot of people like to assume this because originally with IEP there was no requirement or need for it run faster than 100mph on Diesel. Obviously the lack of wires to Bristol has changed things a bit, and the AT300 running on full power as yesterdays IEP was will ideally need to be able to run up to 110mph on the B&H route.

I think yesterdays run should have shut those up questioning IEP/AT300 performance on Diesel, some people do seem to have real difficulty with the fact that had the wires been running to schedule there was never going to be a need for IEP to run faster than 100mph on Diesel, or just because it was specified to only run at 100mph didn't mean to say it wasn't capable of going faster. While the AT300's for the south west may need to go faster then 100mph on Diesel but then that a different contract and different specification.

 

[II]

Yes indeed. I've long been of the opinion that better initial acceleration, better and more consistent brakes and most importantly shorter dwell times at stations due to power operated doors, will mean there's very little difference in the journey times these trains will be able to offer under diesel power.

Reasonably long sections such as Paddington to Reading (which hopefully won't be diesel for very long at all), Reading to Swindon, and Swindon to Bristol Parkway will take slightly longer, but I can't see overall through journey times being much slower at all.

I have more concerns about the engines being run so hard day in day out and the potentially dramatic reduction in performance if one of them fails - especially on a 5-car train.

 

[deltic08]

OK I give in.
However unlike Badminton they won't be trying to reach 90+mph uphill via Sapperton (line speed 50/60).

True. I used to love watching or riding behind double headed Castles pound up to Sapperton Tunnel on the Cheltenham Spa Express. Not so good once inside the tunnel even though easing to 1 in 100.

The daily Fishguard-Paddington parcels train, also Castle hauled, ran via Gloucester. This was even heavier than the passenger trains usually taking a pilot engine from Stroud. This produced an awesome sound along the Valley.

 

[najaB]

I have more concerns about the engines being run so hard day in day out and the potentially dramatic reduction in performance if one of them fails - especially on a 5-car train.

Just to point out, that the Class 800s have a >900hp engine being run at 750hp. So a 'hard running' 800 is still only using c. 85% of rated continuous output.

 

[spark001uk]

Just to point out, that the Class 800s have a >900hp engine being run at 750hp. So a 'hard running' 800 is still only using c. 85% of rated continuous output.

As opposed to the 802 then, in the manner that flat out really will be flat out?

 

[najaB]

As opposed to the 802 then, in the manner that flat out really will be flat out?

I'm not sure if they are going to use the full rated capacity, only that they will be using more of it. And that's not factoring in that MTU have likely done what most manufacturers do and set the rated continuous output somewhat lower than the theoretical maximum.

 

[LNW-GW Joint]

I have more concerns about the engines being run so hard day in day out and the potentially dramatic reduction in performance if one of them fails - especially on a 5-car train.

Indeed, there are 2 issues:
(1) can the IEPs match HST performance on diesel, on routes planned to be wired
and (2) can DfT/GWR afford the increased leasing costs for doing so, because of the higher maintenance/lifetime costs
A Yes answer to (1) doesn't necessarily also mean Yes to (2).
They are already due to pay higher leasing charges for the electric IEPs converted to bi-mode.

 

[Tracked]

Just seen it heading through Doncaster at around 16:50, 9-car unit, got a photo but it's not great quality as it's on my mobile & I was carrying stuff

 

[800001]

Just seen it heading through Doncaster at around 16:50, 9-car unit, got a photo but it's not great quality as it's on my mobile & I was carrying stuff

800101 had been out on test from Doncaster IEP depot - Newcastle.

 

[D1009]

Indeed, there are 2 issues:
(1) can the IEPs match HST performance on diesel, on routes planned to be wired
and (2) can DfT/GWR afford the increased leasing costs for doing so, because of the higher maintenance/lifetime costs
A Yes answer to (1) doesn't necessarily also mean Yes to (2).
They are already due to pay higher leasing charges for the electric IEPs converted to bi-mode.

There is also the issue of fuel capacity. I believe it's been established if Didcot is the limit of electric operation, the 800s will not last a full day without needing refuelling. Presumably if they were run on the full rated power they would use even more fuel.

 

[47802]

There is also the issue of fuel capacity. I believe it's been established if Didcot is the limit of electric operation, the 800s will not last a full day without needing refuelling. Presumably if they were run on the full rated power they would use even more fuel.

Well I imagine they have got 2 choices with that then, either go for the 802 size fuel tanks on some or all the units, or alter the diagrams and probably not release HST's on a one for one basis with IEP

 

[class26]

Well I imagine they have got 2 choices with that then, either go for the 802 size fuel tanks on some or all the units, or alter the diagrams and probably not release HST's on a one for one basis with IEP

or get the electrification finished !

 

[Pete_uk]

Any information on the sounds inside the passenger compartment from the engines?

 

[D365]

I can't remember if it was confirmed true or not but I might have read somewhere that the Class 800 fuel tanks might be substituted with the larger ones from the Class 802 design?

 

[hwl]

Indeed, there are 2 issues:
(1) can the IEPs match HST performance on diesel, on routes planned to be wired
and (2) can DfT/GWR afford the increased leasing costs for doing so, because of the higher maintenance/lifetime costs
A Yes answer to (1) doesn't necessarily also mean Yes to (2).
They are already due to pay higher leasing charges for the electric IEPs converted to bi-mode.

A few thoughts:
a) The IEP Dwell time should be lower due to non manual doors and the timetabling risk that door(s) isn't/aren't closed.
b) IEP acceleration and braking even at original spec on diesel should be far better than HST.

So that might produce a higher performance without needing too much time at higher rated engine power output (and hence fuel consumption) to compensate for the less than 125mph max speed. Especially if lots of running at less than 125mph and lots of stop the top speed matters less. The via Oxford services would have virtually all the high speed running under electric so might make the most sense in the circumstances if worrying about fuel levels as there would be the least difference overall in terms of extra Diesel running.

c) I haven't been following the GW electrification ultra closely but I assume that the 2 main issues that will caused delays on the Didcot - Bristol Parkway route are at Steventon then the Cotswold AONB section resulting in the December 2018 go live date with the other parts able to be completed far sooner, the question is could they be energised sooner as well? E.g. current piling in Wooton Basset Area but theoretical go live in 22 months...
Similar situation for Bristol Parkway - Cardiff presumably a useful section could be energised earlier than Decmeber 2018 given the amount of work completed to date (piling, bridge rebuilding, resignalling)

So would another section or 2 available earlier reduce a sensible amount of diesel running in terms of refuelling and diagramming?

 

[Dave1987]

Reading February MR 'Informed Sources' gives a rather more pessimistic view. RF's sources claim that London to Bristol will be 15 minutes slower than today. Dwell times are not going to be that much shorter because of the length of the carriages and they are end doors. RF's calculations show that even with the distributed traction the pure fact that the engines are derated means that they will be losing time compared to a HST because a HST has 25% more tractive effort per tonne. He also says there is considerable pressure on the DFT to get Agility trains to allow the engines to be put up to full commercial rating, at a cost no doubt.....

He says the easy way out of the mess is to allocate them to Oxford services.

 

[47802]

Reading February MR 'Informed Sources' gives a rather more pessimistic view. RF's sources claim that London to Bristol will be 15 minutes slower than today. Dwell times are not going to be that much shorter because of the length of the carriages and they are end doors. RF's calculations show that even with the distributed traction the pure fact that the engines are derated means that they will be losing time compared to a HST because a HST has 25% more tractive effort per tonne. He also says there is considerable pressure on the DFT to get Agility trains to allow the engines to be put up to full commercial rating, at a cost no doubt.....

He says the easy way out of the mess is to allocate them to Oxford services.

I think I would sceptical about his dwell time comments given IEP has powered end doors and only up to 4 more seats per carriage than a GWR HST also with end doors but manual. Also the TGS in an HST has 76 seats with only 1 door entry where as IEP driving trailer which I think has only 1 entry available to passengers has 56 seats standard class.

 

[hwl]

I think I would sceptical about his dwell time comments given IEP has powered end doors and only up to 4 more seats per carriage than a GWR HST also with end doors but manual.

And RF certainly doesn't like IEP and has always been pessimistic about them.