Potential use for Mark 4 coaches

[Stephen Lee]

I wondered which TOC can use them once displaced from LNER, but just ask if Chiltern Railways can be a good idea so as to make more Chiltern Mainline Services loco-hauled.

 

[Energy]

Are there locos to haul mk4s though if Chiltern got them? I don't think any 68s would be available and although 67s would be available Chiltern's franchise ends in about a year and a half, is that long enough to justify modifying 67s to work with mk4s?

Chiltern does need more capacity but I don't think more loco hauled sets are the answer, they aren't particularly space efficient for platforms anyway with 2 carriages of space being taken up. Chiltern having more loco hauled sets has been discussed before in other Chiltern threads.

 

[The Planner]

Where are Chiltern keeping all these loco hauled extras, presuming they are keeping all their units? As for the franchise ending, they will either end up with a direct award or William's will solve it all.

 

[Energy]

Where are Chiltern keeping all these loco hauled extras, presuming they are keeping all their units? As for the franchise ending, they will either end up with a direct award or William's will solve it all.

Don't think Chiltern has much spare depot space?

 

[Neptune]

There are very few practical uses for the mk4’s going forward.

Chiltern could potentially replace the mk3’s like for like as no more 68’s would be required however, the mk3’s are up to PRM standards so would be pretty pointless replacing them. It’s not really practical to expand their loco hauled fleet as mentioned by others.

I suspect that the vast majority of the mk4’s will end up scrapped.

 

[markymark2000]

Can MK4s be worked with 43s either end?

 

[Nym]

Are there locos to haul mk4s though if Chiltern got them? I don't think any 68s would be available and although 67s would be available Chiltern's franchise ends in about a year and a half, is that long enough to justify modifying 67s to work with mk4s?

You don't need to modify the 67s at all, it's the Mk.4s and the DVT that need the modification, mostly the DVT to be honest, just tweaks and a bit of wiring in the Mk.4s.

Can MK4s be worked with 43s either end?

Yes, but you'd still need the DVT or a pair of TOEs and a load of mods to one of them.
You'd also need to significantly modify the ETS supply on the 43, or the converters and aux supply on the Mk.4s.

 

[hexagon789]

Can MK4s be worked with 43s either end?

Not without several mods, no

 

[hexagon789]

You don't need to modify the 67s at all, it's the Mk.4s and the DVT that need the modification, mostly the DVT to be honest, just tweaks and a bit of wiring in the Mk.4s.

Simpler to convert Mk4s to AAR than 67s to TDM?

 

[ainsworth74]

Simpler to convert Mk4s to AAR than 67s to TDM?

Certainly when it came to Mk3s and Mk3 DVTs that was the approach taken.

 

[hexagon789]

Certainly when it came to Mk3s and Mk3 DVTs that was the approach taken.

I guess there's also the element of reducing flexibility with the 67s themselves. If you only convert some then you end up with effectively two classes of 67 those with AAR and those with TDM whereas the coaches are only likely to work in fixed sets within their own sphere of operations so it's less of a problem.

You don't have operators with the same type of coaching stock using different push-pull control systems.

 

[Nym]

Simpler to convert Mk4s to AAR than 67s to TDM?

Much simpler.

There is already a design to convert Mk.4s to AAR, and then you're not restricting yourself to spesific 67s.

And finally, the information in a TDM datagram bears sod all resemblance to what the GE locomotives need to be seeing on AAR.

TDM looks like this;



and AAR looks like this;


Apologies to those with screen readers, but it's a lot of information to re-type.

There is really no way to relate one set to the other without a lot, and I mean a lot of work.


EDIT:

You also don't need to remove the ability to use TDM when AAR is fitted, it can remain compatible with both, it generally isn't, but it can.

 

[hexagon789]

Much simpler.

There is already a design to convert Mk.4s to AAR, and then you're not restricting yourself to spesific 67s.

And finally, the information in a TDM datagram bears sod all resemblance to what the GE locomotives need to be seeing on AAR.

TDM looks like this;
View attachment 78186


and AAR looks like this;
View attachment 78187

Apologies to those with screen readers, but it's a lot of information to re-type.

There is really no way to relate one set to the other without a lot, and I mean a lot of work.


EDIT:

You also don't need to remove the ability to use TDM when AAR is fitted, it can remain compatible with both, it generally isn't, but it can.

So it is more flexible. I could be wrong here but I believe TDM allows fully variable power settings but AAR has only the traditional 8-notches of US diesel power handles?

Also, that document you got those pieces from information from, can you remind what it is? I've seen it before a while ago but I cannot for the life of me recall where and it may answer a question on another forum regarding the TDM system with respect to 86/2s and DBSOs.

 

[Nym]

TDM is an 8 bit traction setting, where AAR is 3 bit, so 256 positions vs 8 positions, implimented with the Engine Speed A through D valves.

It's an RSSB Document "Historical Data ... Coupling" etc.

 

[hexagon789]

TDM is an 8 bit traction setting, where AAR is 3 bit, so 256 positions vs 8 positions, implimented with the Engine Speed A through D valves.

It's an RSSB Document "Historical Data ... Coupling" etc.

I imagine AAR is much older hence the less 'bits' it can cope with

 

[Nym]

Is also a single wire control standard compared with TDM's two wire, 64 bit microprocessor controlled comms network.

Kind of laying the way for later systems, such as FDM, and ultimately packet based data train control networks (TCNs) like WTB (Part of the MVB standard), CANBUS and ETB (Ethernet).

 

[Stephen Lee]

Are there locos to haul mk4s though if Chiltern got them? I don't think any 68s would be available and although 67s would be available Chiltern's franchise ends in about a year and a half, is that long enough to justify modifying 67s to work with mk4s?

Chiltern does need more capacity but I don't think more loco hauled sets are the answer, they aren't particularly space efficient for platforms anyway with 2 carriages of space being taken up. Chiltern having more loco hauled sets has been discussed before in other Chiltern threads.

Class 88s are available for use i believe or i think TPE can power some loco-hauled sets with Class 88s and cascade 68s to Chiltern.....

 

[SeanG]

Class 88s are available for use i believe or i think TPE can power some loco-hauled sets with Class 88s and cascade 68s to Chiltern.....

Might have a problem west of Colton Junction, the 88s only have a last mile diesel engine.

 

[Stephen Lee]

Might have a problem west of Colton Junction, the 88s only have a last mile diesel engine.

Class 88s are dual mode

 

[t_star2001uk]

Class 88s are available for use i believe or i think TPE can power some loco-hauled sets with Class 88s and cascade 68s to Chiltern.....

Also, do the TPE 68's use the same electrical connection as the Chiltern ones....

 

[Stephen Lee]

Are there locos to haul mk4s though if Chiltern got them? I don't think any 68s would be available and although 67s would be available Chiltern's franchise ends in about a year and a half, is that long enough to justify modifying 67s to work with mk4s?

Chiltern does need more capacity but I don't think more loco hauled sets are the answer, they aren't particularly space efficient for platforms anyway with 2 carriages of space being taken up. Chiltern having more loco hauled sets has been discussed before in other Chiltern threads.

I have forgotten some class 67 are stored for a couple of years, for Class 6ixty 8ight there will be 2 available from Scotrail when they are being displaced from DMUs cascaded from Inter7City Services....

 

[hexagon789]

Class 88s are dual mode

938hp isn't going to get you much speed particularly with an ETS load

 

[Energy]

938hp isn't going to get you much speed particularly with an ETS load

The 68s have about 4x that.

 

[Neptune]

Class 88s are available for use i believe or i think TPE can power some loco-hauled sets with Class 88s and cascade 68s to Chiltern.....

A few problems with that plan:-

The class 88’s would not be able to power a 5 coach mk5 set with full hotel power on their tiny diesel engine very well. I don’t think they’d get over the Pennines very well if at all for a start.

TPE have 13 loco hauled sets, there are only 10 class 88’s.

Are there many if any class 88’s spare?

I think looking for a solution to use mk4 coaches somewhere, anywhere, is loco hauled nostalgia at best or trying to solve already solved problems by throwing unnecessary money at it at worst.

 

[43096]

Class 88s are dual mode

Please go and have a look at the facts. The reasons why diesel passenger workings with 88s are a non-starter has been done many times. It is just utterly ridiculous that people keep posting this “idea”.

 

[Energy]

I think we should stop suggesting loco hauled for lot of routes to be honest and treat it more as a nice thing when a TOC chooses it. Short term I can't see Chiltern getting more loco hauled sets, they have to find the space to maintain them in their depots, train more drivers and modify the mk4s for AAR. Long term in the next franchise it would make more sense to order new MUs such as a bimode 397 or 802/810 as they are cheaper, especially the latter, right now. Anyway the Williams review should be out by the next Chiltern franchise so that will dictate a lot.

Going back to my first line of this reply, loco hauled sets don't make much sense for operators. The loco takes up space and apart from noise there isn't really any upsides. The mk5as aren't too flexible as they are basically an unpowered multiple unit so they can't easily have carriages moved around.

 

[hexagon789]

The 68s have about 4x that.

Well of course, but the post is was replying to was talking about 88s being dual-mode and I was making the point that on diesel they don't have enough power to maintain a particularly high-speed with ETS-enabled.

A 3,805hp 68 is a different matter entirely

 

[ainsworth74]

I think we should stop suggesting loco hauled for lot of routes to be honest and treat it more as a nice thing when a TOC chooses it. Short term I can't see Chiltern getting more loco hauled sets, they have to find the space to maintain them in their depots, train more drivers and modify the mk4s for AAR.

I've said this before regarding Chiltern but if we rewind to 2010 and gave them the choice between a fleet of 67s and Mk3s without a home or a fleet of 170s without a home they'd have chosen the 170s every day of the week. The same goes for Scotrail and their Mk2s on the Fife Circle (and indeed as soon as they've got the stock to ditch the Mk2s they're doing so). The only TOCs that's gone for loco haulage from new is TPE and that was supposed to be because the Mk5s could be in service quickly. With the way things have shaken out I bet they'd have just ordered more 802s if they had their time again.

To fill a stopgap (ScotRail, Greater Anglia, etc) or as a small expansion to an already running loco hauled operation (TfW) where you can almost plug and play sure using the Mk4s makes sense. But the chances of someone chucking out a load of MUs in favour of loco hauled is slight I'd have said. The most Chiltern (or more accurately a future Chiltern franchise) might do is replace their existing fleet of Mk3s with Mk4s but I think that's unlikely personally.

The cold reality is that a big chunk of Mk4s are likely to go under the torch before too long...

 

[Energy]

I've said this before regarding Chiltern but if we rewind to 2010 and gave them the choice between a fleet of 67s and Mk3s without a home or a fleet of 170s without a home they'd have chosen the 170s every day of the week. The same goes for Scotrail and their Mk2s on the Fife Circle (and indeed as soon as they've got the stock to ditch the Mk2s they're doing so). The only TOCs that's gone for loco haulage from new is TPE and that was supposed to be because the Mk5s could be in service quickly. With the way things have shaken out I bet they'd have just ordered more 802s if they had their time again.

To fill a stopgap (ScotRail, Greater Anglia, etc) or as a small expansion to an already running loco hauled operation (TfW) where you can almost plug and play sure using the Mk4s makes sense. But the chances of someone chucking out a load of MUs in favour of loco hauled is slight I'd have said. The most Chiltern (or more accurately a future Chiltern franchise) might do is replace their existing fleet of Mk3s with Mk4s but I think that's unlikely personally.

The cold reality is that a big chunk of Mk4s are likely to go under the torch before too long...

The reason why Wrexham and Shropshire got loco hauled sets was because nothing else was available and brand new carriages for open access are rare, East Coast Trains is the only one but they are operating on an already popular route and they have ordered AT300s which aren't too expensive. The class 172 order shows Chiltern would rather have new DMUs, if they would have wanted more loco hauled sets they would have converted more to free up 168s instead of ordering a few 172s.

Chiltern have said the 68 loco hauled sets perform similarly to a DMU in terms of acceleration, however I would imagine that the time spent at stations would be longer.

 

[ainsworth74]

The reason why Wrexham and Shropshire got loco hauled sets was because nothing else was available and brand new carriages for open access are rare, East Coast Trains is the only one but they are operating on an already popular route and they have ordered AT300s which aren't too expensive. The class 172 order shows Chiltern would rather have new DMUs, if they would have wanted more loco hauled sets they would have converted more to free up 168s instead of ordering a few 172s.

Absolutely. See also Grand Central to Blackpool and indeed Grand Central to Sunderland back in the day (those HSTs had no other home when they brought them into service) all using spare stock which had no other home.