GWR Class 800

[404250]

What about 10 car vs 9 car. Must be some performance differences? 9 car more aero, but less average power per car.

 

[swt_passenger]

What about 10 car vs 9 car. Must be some performance differences? 9 car more aero, but less average power per car.

Have you seen post #11397, a few posts back?

 

[Kite159]

All 800s are in service, and all of the 802s have been delivered

Has 800001 & 800002 finally entered service?

 

[cactustwirly]

Has 800001 & 800002 finally entered service?

Not 100% sure but I think so, definitely 800002 is.

 

[patstonuk]

I rarely comment on here - but I see the usual seemingly paranoid anti-GW/First commentary as well as an equally strange inability by some (including a GW driver?) to appreciate the raison d'être with 5 versus 9 into Cornwall. Why, I wonder, are so many incapable of understanding the intended strategy which, until it is all in place, may lead to sub-optimal service provision?

 

[Clarence Yard]

Has 800001 & 800002 finally entered service?

802114 is in the country but hasn’t been offered to GWR for acceptance yet. It should be in the next few days.

800001/2 are not in passenger service yet. Each will require a refit lasting a few weeks and the first is due to undergo the required mods shortly.

 

[404250]

Have you seen post #11397, a few posts back?

Yes. It doesn't answer this question.

 

[Kite159]

802114 is in the country but hasn’t been offered to GWR for acceptance yet. It should be in the next few days.

800001/2 are not in passenger service yet. Each will require a refit lasting a few weeks and the first is due to undergo the required mods shortly.

Ah good, I didn't miss them coming into passenger service

 

[Mag_seven]

802114 is in the country but hasn’t been offered to GWR for acceptance yet. It should be in the next few days.

I assume that will be the last 9 car 802 to be accepted as I was able to "red pen" 802113 this evening!

 

[TommyJ]

Indeed. I will not sign that on a point of principle.

Much as I think GWR does need buffets bringing back, I detest the railway unions. The RMT give even less of a stuff about the punters than WorstGroup do, and that is saying something.

I agree. I support bringing back the buffet but the RMT is the enemy of the passenger.

 

[Noddy]

I rarely comment on here - but I see the usual seemingly paranoid anti-GW/First commentary as well as an equally strange inability by some (including a GW driver?) to appreciate the raison d'être with 5 versus 9 into Cornwall. Why, I wonder, are so many incapable of understanding the intended strategy which, until it is all in place, may lead to sub-optimal service provision?

I agree. I support bringing back the buffet but the RMT is the enemy of the passenger.

I wish there was a like button on here.

 

[Bikeman78]

The current timetable seems to be built around 3 minute headways - but in practice it seems impossible for one train to follow another out of Paddington and into Reading 3 minutes later without some kind of signal check - even when train A runs cleanly into its assigned platform. I don't know how long it takes for the block sections to clear in order for the route and signals to be set for the following train, but what i do know, is that the following train always seems to encounter cautionary signals further back towards Twyford causing it to brake earlier and extend its journey time into Reading. Also the fact that Reading starter is always red causes a much more cautionary approach due to ATP and TPWS issues as well as defensive driving rules!

The situation at Reading is bizarre indeed. Typically a train will come to a stand in platform 8/9 10/11 and then a member of platform staff almost immediately pushes the Train Ready To Start (TRTS) button. Then the route clears, usually to green. This sometimes happens before the doors have even unlocked so the train is not ready to start at all! I cannot see any advantage of this over having the route clear (assuming no conflicting moves) before the train arrives. If a problem occurs whilst the train is stopped, the driver will still have to ring the signaller to have the road put back to red.

 

[Bikeman78]

Which underlying issue might that be? That GWR is operated by First Group?

If you want to pretend we still live in October 1976, that's up to you, but the world has changed since then and so has the railway and the job it is required to do. And the average passenger wants a robust, reliable timetable that gets them where they want to go at the advertised time.

The new timetable will result in a lot of GWR services with typical end to end journey times close to what prevailed some years ago, but in most cases they will be making rather more stops along the way.

I think it's a balancing act. Too much slack and it gets tedious. On recent trips on the WCML and ECML I've got the impression that the trains are really going for it but only just keep time. Personally I prefer that.

 

[Thunderer]

Oh dear it seems 1a85 was formed of just 1 x 5 car 802 on good Friday as far as Plymouth. I drove the same service earlier in the week and the passenger count said 450 passengers by liskeard, so must of been extremely cosy on good Friday packed into a 5 car!!! Just another example where the west is stitched up by using none proper length trains....

As a passenger (speaking from a few experiences of this) its an awful experience. Even though practically all the 800 and 802 fleet have been delivered now, it is inevitable this will still happen from time to time. I still say they build too many 5 car and not enough 9 car sets for GWR (only 35 x 9 car sets) and at any one time, its pretty nailed on that all 35 won't be available for service (servicing schedules, faults etc). Got to say though as a driver, you got the most comfortable seat in the whole train ha...sitting on the toilet for your journey is more comfortable than those standard seats.

 

[tasky]

Did a return journey from Paddington to Penzance over the long weekend, with an IET in both directions.

The one thing that really stood out: the reservation system on these new trains is totally broken

On the way out the computer reservation system just completely failed to load, including the digital carriage numbers, which were showing some kind of flashing checkerboard pattern on the outside of the train where the numbers should be. Nobody knew what to do or where to get on, and as usual GWR had announced the train platform about 10 minutes before departure and insisted on checking tickets at the gate, so it was an almighty crush: totally Lord of the Flies.

About one minute before the scheduled departure time when everyone was already on the train the carriage numbers appeared, and then after the train was moving the guard confirmed over intercom that all reservations were void and people could sit anywhere they liked. Lots of people getting on at intermediate stops with reservations had to stand, including families who had booked to sit together.

On the way back from Penzance the train crew seemed to have totally given up on the electronic reservation system and had just put the old paper slips in the back of the seats.

It's really incredible: loading a simple database is the most basic thing a computer can do, it isn't new technology, it has been consumer-grade for decades and could be programmed in Microsoft Excel. So why do electronic reservation systems like this constantly fail? It's not a small problem, it's massively disruptive to the entire service.

 

[Railperf]

Yes. It doesn't answer this question.

Too much sla

I think it's a balancing act. Too much slack and it gets tedious. On recent trips on the WCML and ECML I've got the impression that the trains are really going for it but only just keep time. Personally I prefer that.

Too much slack seems to encourage slack operating practices. Yes, on some routes the net running times are much more tightly timed - which seems to encourage sharper operating procedures all round. Slack timings encourage more eco driving..but rarely does the timetable seem to recover any quicker due to the padding.

 

[Railperf]

The situation at Reading is bizarre indeed. Typically a train will come to a stand in platform 8/9 10/11 and then a member of platform staff almost immediately pushes the Train Ready To Start (TRTS) button. Then the route clears, usually to green. This sometimes happens before the doors have even unlocked so the train is not ready to start at all! I cannot see any advantage of this over having the route clear (assuming no conflicting moves) before the train arrives. If a problem occurs whilst the train is stopped, the driver will still have to ring the signaller to have the road put back to red.

Hmmm. Was that recently? My experience observing arrivals and departures at Reading are that the TRST button is not pressed until loading/unloading is complete even when the service is running late.

 

[broadgage]

Hmmm. Was that recently? My experience observing arrivals and departures at Reading are that the TRST button is not pressed until loading/unloading is complete even when the service is running late.

But surely the pressing of the button means "train ready to start" and not "train arrived n platform"

 

[coppercapped]

I think that all the other sources of resistance that you mention will be insignificant compared to that huge volume of low pressure at the rear of train sucking it backwards. You can provide some real numbers to prove that I'm wrong if you have them.

If I assume a rough example of there being normal air pressure at the front of the train and a vacuum at the back, the pressure difference between the two will be 100kN per square meter. If I guess that the train has 6 square meters cross sectional area we multiply those to get 600kN. If we multiply that by 44 meters per second (about 100mph) we get 26MW. That's significantly more than the output power of the train (120kW per axle), so obviously there is still reasonable air pressure behind the train, but it shows how significant the air pressure behind the train could potentially be.

Your assumptions are incorrect - aerodynamics does not work like that. Of course there is a low pressure area behind a train - but it is most certainly not a vacuum (by which I understand you to mean a pressure of a few per cent of atmospheric) or anything like one. If the tail is well shaped air flows down and around the rear end to rapidly fill the space behind a train. This can be seen in the early days of HST operation where the air flow which closely followed the curves between the roof and the front of power car carried the diesel exhaust over the end of the trailing power car and covered the windscreen with a oily residue. The smoky exhaust reached rail level. The addition of a plate over the top of the engine room and spaced a few inches above it and through which the exhaust pipes protruded helped to reduce this effect by entraining a flow of clean air between the exhausts and the windscreen.

Generally the power needed to push an object through a fluid increases as the cube of the velocity. In its attempts to apply aerodynamic theory as understood for aircraft to fast moving bodies close to the ground BR Research found that rounding off the edges of the leading and trailing ends of a train by a few per cent of the width and height of the train prevented vortices developing on the corners which would have had the effect of increasing the drag. All trains built subsequently which have operating speeds greater than 75mph or so have curved edges. Equally in the 1930s Wunibald Kamm discovered that a long tapered tail was not necessary to reduce the drag acting on fast cars - look up 'Kamm tail'. A sharply cut-off rear end, like the rear of many trains, does not mean, per se, that the design is unaerodynamic.

There is an active thread discussing coasting of trains, see here. In one of the posts there is a link to a graph produced by Alstom which shows a Pendolino coasting from Tring (passed at 125mph) to Euston using NO traction current - a distance of 34 miles. Admittedly it is slightly downhill but if the tail drag was as significant as you claim this would not have been possible.

 

[JamesRowden]

Your assumptions are incorrect -

Stating the very thing that I stated in my post (about my hypothetical example which in no way was supposed to be an accurate model for air resistance, just an example of the significance of air pressure). And still no real numbers in your post to prove the insignificance of the force produced by the low pressure behind the train relative to the sum of the other various resistances along the train.

 

[43096]

But surely the pressing of the button means "train ready to start" and not "train arrived n platform"

The staff are probably used to how long it takes Thames Valley Signalling Centre to respond (and for those who have been there some time, the utterly useless Reading Panel that preceded it).

 

[Railperf]

But surely the pressing of the button means "train ready to start" and not "train arrived n platform"

Exactly!

 

[Railperf]

The staff are probably used to how long it takes Thames Valley Signalling Centre to respond (and for those who have been there some time, the utterly useless Reading Panel that preceded it).

Isnt the TRTS linked to automatic route setting? Does the signaller have to manually respond 2 a TRTS call?

 

[Nippy]

The TRTS is linked to the ARS.

 

[Master29]

Seat totals and it was cheaper to convert the ordinary coaches than convert the buffet cars. It was an option that was looked at.



Swansea can’t deal with electric repairs so if it is isolated on arrival, it will go out on diesel. As the sets are currently operating on HST times, no big deal. But when the new timetable comes in December, it will be so Q paths will have to be put in to swap units out between Stoke Gifford and Maliphant. .

I was under the impression that HST`s would be gone by the introduction of this May`s timetable changover and services would then be run on IET timings?

 

[JN114]

IET timings are much faster, they’d need a whole rewrite of the entire timetable.

 

[swt_passenger]

I was under the impression that HST`s would be gone by the introduction of this May`s timetable changover and services would then be run on IET timings?

If you haven’t been reading this thread regularly, you may have missed a number of explanations that the timetable change will not be until December. The May possibility was only ever assumed by some posters, but in hindsight there was no evidence for it.

 

[Bikeman78]

Hmmm. Was that recently? My experience observing arrivals and departures at Reading are that the TRST button is not pressed until loading/unloading is complete even when the service is running late.

Two or three months ago. Perhaps the policy has changed. I'll make a point of observing what goes on next time I'm there.

 

[Geogregor]

I had finally chance to try the IETs. I went to Totnes and back on Eastern Sunday, both way 2x5 coach class 802s (didn't check the unit numbers, I'm not that geeky yet )

So, let's get the issue of seats out of the way. Personally I didn't find them particularly hard but I had issue with the profile of the seats, found the back "too straight". Overall not as much of disaster as one could think reading hysteric coverage. Plain average, could be better, could be worse.

There is quite large amount of padding in the timetable. On the way west we had over 10 min wait in Reading and on the way back we were early passing through Bristol and so early in Reading that we had to wait 20 min for the departure. In fact guard suggested that there is train to Paddington departing earlier from the opposite platform.
I do understand why the padding exists but too much of it makes journey too slow and frustrating.

They had issues with the trolley service. In bot directions they only had trolleys in one unit, luckily in our. Anyway, buffet is something I will miss. It was nice option to stretch legs and hang around it during longer journeys.

Overall I found the units performing relatively well. Ride was smooth, noise level acceptable etc. I hope once the the timetable is rejigged they will speed up the services west.

 

[Bletchleyite]

I had finally chance to try the IETs. I went to Totnes and back on Eastern Sunday, both way 2x5 coach class 802s (didn't check the unit numbers, I'm not that geeky yet )

So, let's get the issue of seats out of the way. Personally I didn't find them particularly hard but I had issue with the profile of the seats, found the back "too straight". Overall not as much of disaster as one could think reading hysteric coverage. Plain average, could be better, could be worse.

It's worth noting that the bases in the newer 802s have not yet collapsed and so are (to me at least) noticeably more comfortable than the older 800 ones.