GN Class 717

jon0844

Veteran Member
Joined
1 Feb 2009
Messages
24,446
Location
UK
Only that the Hertford loop is 70/75mph throughout unless they plan to raise the speed.
That's the question. Is the higher speed designed for a possible increase of line speeds? Or just to enable faster running on the rare occasions they venture on to the fast lines (possibly when ECS)?

It would make sense to build in some future proofing for trains around for another 30 or 40 years.
 
Sponsor Post - registered members do not see these adverts; click here to register, or click here to log in
R

RailUK Forums

Failed Unit

Established Member
Joined
26 Jan 2009
Messages
7,493
Location
Central Belt
The slow lines are a maximum of 75 aren't they? Perhaps there's a plan to raise this in the future? Could possibly help a little if the new trains skip some stops? Certainly for the semi fast trains now consigned to the slows too.
I think the slow on the ECML are actually 90 (with some speed limits in places such as Brookmans park because of the geometry of the platform) Whether they will hit 85mph in normal service is a different question, I guess it is possible on some of the runs such as Hatfield - Potters Bar and New Barnet - Finsbury park. However on the many times that these trains will need to skip stop because of late running the speed will be useful. However biggest impact is how fast the unit starts / stops.
 

choochoochoo

Member
Joined
6 Aug 2013
Messages
647
On a side note, how do they work out the standing capacity of trains ?

is it available floor area divided by the area taken up by a given standardised passenger ? Or do they cram people on and count how many they can squeeze in ?
 

Domh245

Established Member
Joined
6 Apr 2013
Messages
5,386
Location
Nottingham
On a side note, how do they work out the standing capacity of trains ?

is it available floor area divided by the area taken up by a given standardised passenger ? Or do they cram people on and count how many they can squeeze in ?
As I understand it, the former. They take the available floor space and then divide by a target amount of space/passenger. I think that the DfT expectation for metro type carriages is 4 people/sq m (ie 0.25m^2 per passenger) although I think that LU claim a crush capacity of 7 people/sq m.

As for the door buttons, whilst familiarity is a good idea, there is a school of thought that when you have similar but different items it is better to make controls different to help subtly remind people that they are different. That said however, in this case I'd expect that the buttons on the left side wall have been rotated around for comfort's sake - the left hand will be primarily in an up/down orientation anyway whilst being used to drive the train and so the vertical arrangement of buttons prevents having to twist the hand around. Having them vertical also means that the elbow can be kept tucked in, whereas if they were horizontal the arm would want to come round and stick out into the wall.
 

332 > 444

Member
Joined
22 Feb 2007
Messages
531
Location
London
I think the slow on the ECML are actually 90 (with some speed limits in places such as Brookmans park because of the geometry of the platform) Whether they will hit 85mph in normal service is a different question, I guess it is possible on some of the runs such as Hatfield - Potters Bar and New Barnet - Finsbury park. However on the many times that these trains will need to skip stop because of late running the speed will be useful. However biggest impact is how fast the unit starts / stops.
The slow is mainly 75mph past Southgate tunnel, after Hitchin it goes up and down at 75/80mph. Yes Brookmans Park is 55mph on the up/down slow for that reason you state. I can only guess the 85mph is for ECS but I've never driven an ECS at top speed as I've been routed behind stoppers most the time!
 

bramling

Established Member
Joined
5 Mar 2012
Messages
8,132
Location
Hertfordshire / Teesdale
That's the question. Is the higher speed designed for a possible increase of line speeds? Or just to enable faster running on the rare occasions they venture on to the fast lines (possibly when ECS)?

It would make sense to build in some future proofing for trains around for another 30 or 40 years.
I would say it's future proofing, and partly simply that the performance of the train is such that nowadays there's less of a trade-off between performance and top speed - it's quite possible to have cake and eat it too and have both.

Even if the slow lines were rated for more than 75 mph, the closeness of stops means it would likely rarely be achieved. Would of course be useful on the rare occasions they will stray onto the fast lines, however this is even less likely than today with the new timetable.

What I would like to see is the slow lines uprated to at least 90 mph. Outwards of Welwyn Garden City this really would make a difference. 365s, 387s and 700s are quite capable of pushing towards 100 mph on sections like Knebworth-Stevenage and Stevenage-Hitchin, as well as the longer sections north of Hitchin. Hopefully one day this may happen, although I suspect there would be some alignment works required in certain locations, around platforms and bridges, as well as of course resignalling.
 

D365

Established Member
Joined
29 Jun 2012
Messages
7,204
It’s not unheard of for passenger trains to be rated at a higher speed than they will ever operate at for the majority of their working lives...
 

Wivenswold

Established Member
Joined
24 Jul 2012
Messages
1,165
Location
Essex
It’s not unheard of for passenger trains to be rated at a higher speed than they will ever operate at for the majority of their working lives...
Quite, C2Cs Class 357s immediately spring to mind. Even during a short loan spell on Great Eastern they never operated at more than 90mph as they were only used on the Southend Vic line.
 

43055

Member
Joined
8 Mar 2018
Messages
842
Geoff Marshall has uploaded a video of him on the way to the Siemens factory in Germany where the 717's are being built. This video does not show the 717's but a later one will once it is uploaded. From the description it sounds like he has had the chance to drive one on the test track.
 

3141

Established Member
Joined
1 Apr 2012
Messages
1,498
Location
Overton, Hampshire
As I understand it, the former. They take the available floor space and then divide by a target amount of space/passenger. I think that the DfT expectation for metro type carriages is 4 people/sq m (ie 0.25m^2 per passenger) although I think that LU claim a crush capacity of 7 people/sq m.
Ian Walmsley discussed standing capacity in an article in Modern Railways, but it was some time ago and I no longer have it. I recall a figure of 8.3 people per square metre, but I'm not confident about it, even though it sometimes feels like that! The problem is that the spaces in a train carriage (or in a bus) aren't neatly shaped. People standing in the aisle in a commuter train won't conveniently occupy their theoretical space, and they'll place themselves where they can reach a grab handle of some kind even if that means using more than what the designer considers the optimum space. For several real-world reasons, the theoretical capacity is unlikely to be reached.
 

swt_passenger

Veteran Member
Joined
7 Apr 2010
Messages
22,304
There’s quite a bit of info in the 2016 SW franchise ITT, which tries to separate out the reasoning behind the various standing capacities, but it includes this paragraph which suggests it isn’t just a case of measuring the theoretical floor area:

“Measurement of the standing area must assume that any available wheelchair spaces are occupied by wheelchair users, and that all tip-up seats that were counted towards total seating capacity are occupied by seated passengers. Inaccessible areas such as toilets, staff areas, litter bins, equipment cupboards, draught screens, inter-vehicle gangways and spaces between seats are excluded from the available standing area. Standing space within first-class accommodation must also be excluded (unless first class is to be declassified).“

Around pages 73-76:

https://assets.publishing.service.g...loads/attachment_data/file/550983/swf-itt.pdf
 
Last edited:

APUK002

Member
Joined
26 Dec 2016
Messages
315
Geoff Marshall has uploaded a video of him on the way to the Siemens factory in Germany where the 717's are being built. This video does not show the 717's but a later one will once it is uploaded. From the description it sounds like he has had the chance to drive one on the test track.
Part 2 is out
 

jon0844

Veteran Member
Joined
1 Feb 2009
Messages
24,446
Location
UK
When they do arrive will Great Northern be able to train the drivers? I expect any training resources are going to be committed elsewhere for a while.
Question is what training some drivers need. There are drivers doing inner services that can drive a 700. But will they need a shorter course to show the differences between a 700 and 717 or a longer training course?

I think that's still being discussed, as well talk of when some 313s need to go - which may be before there are enough 717s to replace them...
 

332 > 444

Member
Joined
22 Feb 2007
Messages
531
Location
London
I thought they weren't due till the 26th, I didn't see any non yellow fronted trains but then not been in the depot since Thursday.
 

bramling

Established Member
Joined
5 Mar 2012
Messages
8,132
Location
Hertfordshire / Teesdale
Why would Eversholt need them back sooner?
Lack of depot space on the GN?

The only place with a bit of spare space to hold extra trains is Hertford North sidings, and by my calculations this only amounts to 3x 6-car trains - and with security risks too. Perhaps Hitchin up yard at a stretch, although no good for regular preparation, and by no means secure. One wonders if this is going to be another thing the industry are going to “own goal”? With the Thameslink shambles ongoing, perhaps it might be better to hold off the 717s for a bit.
 
Last edited:

Top