Class 93 Tri-mode Loco

[ac6000cw]

Stadler claim that better WSP will make up most of the difference, and they've apparently demonstrated this to DRS' satisfaction at Velim. It's not a new tune - Siemens said the same thing when they convinced DB to buy the Bo′Bo′ ES64F (Br 152) and ES64F4 (Br 189), although they did end up doing a small run of Co′Co′ units for DSB (Litra EG) when 400 kN tractive effort was needed for the Great Belt Tunnel.

I fully accept that a modern Bo-Bo is an excellent general freight loco (and has been for years). But the TE-vs-speed graphs below (from https://www.railengineer.co.uk/class-93-tri-mode-locos-on-order/ ) tell you most of what you need to know if starting heavy trains on gradients is important to you:



I'm sure that if GBRf thought that a Bo-Bo bi-mode could meet their future business requirements, they'd have gone for that with the class 99. But I assume they wanted something that was significantly better than a class 66 overall i.e. could haul longer & heavier trains while lowering the energy costs (thus reducing their haulage costs per tonne). Provided the business is there and they could persuade NR to allow long enough trains, a 2500+ tonne intermodal would be somewhat more efficient than a 1500 tonne one...

As I see it, ROG have their sights on the 'fast freight' market, for which the 93s seem perfectly suited. Back in steam days, railways used passenger and mixed-traffic locos on the same kind of freights. If you are in the US and want your containers 'hustled' across the continent, BNSF and UP will happily sell you (at a premium price) space on a high-priority train with much more power on the front than an ordinary intermodal - UPS/DHL/FedEx/US Postal Service/Amazon etc. do that for some of their business because it's cheaper than trucking or flying it.

 

[XAM2175]

I fully accept that a modern Bo-Bo is an excellent general freight loco (and has been for years). But the TE-vs-speed graphs below (from https://www.railengineer.co.uk/class-93-tri-mode-locos-on-order/ ) tell you most of what you need to know if starting heavy trains on gradients is important to you:

I don't disagree; hence my use of "claim" and "apparently". And indeed also hence my example of the DSB EG order, and your example of the 99s being Co′Co′.

 

[Mollman]

Delete

 

[Nottingham59]

in theory a London Gateway departure dependent on railhead a single 93 *could* haul a fair load to Thames Haven Jct before the pan is raised.

I don't quite follow that distinction between pan up and pan down. I always understood that, below 10mph, the tractive effort (i.e. pulling force) would be the same whatever the energy source. It is only above 10mph that the tractive effort falls away under diesel because of the limited power available. (see the graph in post #391)

As far as I can see, the branch from Gateway to the mainline is almost level. And only carries about 1tph each way. I would have thought the 93's Tractive Effort of 280kN should be enough to haul even a 2500T train from the dockside onto the wires. But maybe that TE won't be achievable in all conditions? As you say, we will have to wait and see what happens in practice.

 

[Richard Scott]

I don't quite follow that distinction between pan up and pan down. I always understood that, below 10mph, the tractive effort (i.e. pulling force) would be the same whatever the energy source. It is only above 10mph that the tractive effort falls away under diesel because of the limited power available. (see the graph in post #391)

As far as I can see, the branch from Gateway to the mainline is almost level. And only carries about 1tph each way. I would have thought the 93's Tractive Effort of 280kN should be enough to haul even a 2500T train from the dockside onto the wires. But maybe that TE won't be achievable in all conditions? As you say, we will have to wait and see what happens in practice.

TE gives it the ability to pull a heavy train from a standing start, it's the power that will allow the train to accelerate at a decent rate. Raising the pan will allow decent acceleration, if on diesel or diesel plus battery the rate of acceleration will be less as will balancing speed.

 

[Peter Sarf]

I don't quite follow that distinction between pan up and pan down. I always understood that, below 10mph, the tractive effort (i.e. pulling force) would be the same whatever the energy source. It is only above 10mph that the tractive effort falls away under diesel because of the limited power available. (see the graph in post #391)

As far as I can see, the branch from Gateway to the mainline is almost level. And only carries about 1tph each way. I would have thought the 93's Tractive Effort of 280kN should be enough to haul even a 2500T train from the dockside onto the wires. But maybe that TE won't be achievable in all conditions? As you say, we will have to wait and see what happens in practice.

TE gives it the ability to pull a heavy train from a standing start, it's the power that will allow the train to accelerate at a decent rate. Raising the pan will allow decent acceleration, if on diesel or diesel plus battery the rate of acceleration will be less as will balancing speed.

My understanding is that the TE (i.e. Tractive Effort) will be limited at low speeds by the available adhesion (how much grip the wheels have on the rails) - law of physics. So at low speed the power of the batteries and/or diesel will exceed what the adhesion will let the loco do. So no need for outside power from the overhead. As speed increases the maximum power that can be used rises so then the use of the overhead becomes necessary to reach the maximum power the adhesion will allow - then its pan up.

It is why a class 08 shunter can shift a whole train but only at a low speed. It does not have enough power to ACCELERATE the train to a speed much more than 5 or 10mph.

 

[Nicholas Lewis]

Don't know!

Those along the main route between the tunnel & Wembley/Willesden must do, as heavy 92 hauled freights have previously used this route.

Correct Dollands Moor to North Pole via Maidstone East/Orpington/Redhill was reinforced to high current railway standard (6800 Amps) in the early 1990's for Eurostar and Class 92 working. However, the conversion of the reed track circuits between redhill and clapham jcn was deferred in 1994 when Railtrack was first created so they have never run that way under power. Those track circuits have been converted to TI's or axle counters since but without a safety case they still wouldn't be allowed to run and no one is going to pay for that now.

If the maximum amount of power that can drawn elsewhere is limited, though, this is where I was wondering if batteries & diesel backup could make a difference. In the same way that the idea seems to be that the batteries can offer extra power to the diesel units when starting off, etc, could the same be done to assist when on 3rd rail sections with limited power. I've no idea how these things work.

All of the Southerns main lines have received power reinforcements over the last decade in response to increased frequencies, train lengths and modern stock so a DC feright locomotive could have a wider oeprating area on the juice. The branch lines are less viable but with clever electronics and GPS they could limit what is taken from 3rd rail and top up the rest with a diesel/battery but doubt any operator would pay for the extra safety case work which is always far more involved than 25kV due to the way the negative bonding needed for DC railways spreads the return currents far and wide. At least GBs 73's still run on DC when they can and hopefully have a few more years in them yet.

 

[Irascible]

My understanding is that the TE (i.e. Tractive Effort) will be limited at low speeds by the available adhesion (how much grip the wheels have on the rails) - law of physics. So at low speed the power of the batteries and/or diesel will exceed what the adhesion will let the loco do. So no need for outside power from the overhead. As speed increases the maximum power that can be used rises so then the use of the overhead becomes necessary to reach the maximum power the adhesion will allow - then its pan up.

Somewhat limited by the electricals also, which is why there's a flat line at low speed, and why in the US sometimes they attach a second locomotive with the powerplant removed & wired with power cables from the first, for low speed work.

 

[furnessvale]

Somewhat limited by the electricals also, which is why there's a flat line at low speed, and why in the US sometimes they attach a second locomotive with the powerplant removed & wired with power cables from the first, for low speed work.

A "slug". I advocated doing this on the WCML over Shap and Beattock. A single 86 has more than enough horses to move heavy freight up such gradients, but on a wet day, with a check at Scout Green, did not have the adhesion to cope. An 86, semi permanently coupled to a slug made from another 86 would have been perfect for the job.

 

[Meerkat]

A "slug". I advocated doing this on the WCML over Shap and Beattock. A single 86 has more than enough horses to move heavy freight up such gradients, but on a wet day, with a check at Scout Green, did not have the adhesion to cope. An 86, semi permanently coupled to a slug made from another 86 would have been perfect for the job.

I can see why it might be worth it for diesels but for electric is there any real advantage over just using a real live second 86? There would be disadvantages in having a longer 'power unit' of which half couldn't move independently.

 

[furnessvale]

I can see why it might be worth it for diesels but for electric is there any real advantage over just using a real live second 86? There would be disadvantages in having a longer 'power unit' of which half couldn't move independently.

Yes, I see your point. The advantage of less parts requiring maintenance is much reduced with an electric compared to a diesel.

 

[Nottingham59]

Anyway, given the claimed operating cost advantages over the Class 66, it seems to me that class 93s will be highly competitive over 66s for many intermodal flows. And wherever there may be concerns over adhesion on gradients in wet weather, then a Class 99 would be competitive instead, with a greater tractive effort than even a 66.

Which means that many intermodal freight services are likely to become bimode over the next decade. Does that mean that heavily-used freight lines like Felixstowe to Peterborough will have soon a postive economic case for electrification?

 

[Bald Rick]

Which means that many intermodal freight services are likely to become bimode over the next decade. Does that mean that heavily-used freight lines like Felixstowe to Peterborough will have soon a postive economic case for electrification?

It more likely means the opposite.

What it does mean is that Government is going to have to fork out for quite a few power upgrades on existing electrified lines.

 

[Energy]

Anyway, given the claimed operating cost advantages over the Class 66, it seems to me that class 93s will be highly competitive over 66s for many intermodal flows. And wherever there may be concerns over adhesion on gradients in wet weather, then a Class 99 would be competitive instead, with a greater tractive effort than even a 66.

Depends on what the 66 is being used for, lighter weight stuff (e.g they are occasionally used on the Cal Sleeper or for nuclear waste) the 93 will be competitive, for the heavy weight like the quarry trains thats really for the class 99.

 

[Swanley 59]

Depends on what the 66 is being used for, lighter weight stuff (e.g they are occasionally used on the Cal Sleeper or for nuclear waste) the 93 will be competitive, for the heavy weight like the quarry trains thats really for the class 99.

I thought that the DRS Mossend - Daventry "Tesco" service, via the ECML, was intended for electric haulage throughout? Yet whenever I see it pass, it is invariably hauled by a Class 66. I don't if that's because of a shortage of 88s, or because of the power supply north of Newcastle isn't up to the job.

When the Class 93 enters service, will it be rostered for this service and thereby go some way to reducing the number of diesels running under the wires?

 

[Class15]

I thought that the DRS Mossend - Daventry "Tesco" service, via the ECML, was intended for electric haulage throughout? Yet whenever I see it pass, it is invariably hauled by a Class 66. I don't if that's because of a shortage of 88s, or because of the power supply north of Newcastle isn't up to the job.

When the Class 93 enters service, will it be rostered for this service and thereby go some way to reducing the number of diesels running under the wires?

The Mossend To Daventry train goes via the WCML and is 88-hauled, no?

 

[Peter Sarf]

I thought that the DRS Mossend - Daventry "Tesco" service, via the ECML, was intended for electric haulage throughout? Yet whenever I see it pass, it is invariably hauled by a Class 66. I don't if that's because of a shortage of 88s, or because of the power supply north of Newcastle isn't up to the job.

When the Class 93 enters service, will it be rostered for this service and thereby go some way to reducing the number of diesels running under the wires?

Assuming this is when it is diverted away from the North WCML the train will not be electrically hauled as parts of the route will be on non-electrified lines. Thats unless it goes via London !.

 

[Suraggu]

I thought that the DRS Mossend - Daventry "Tesco" service, via the ECML, was intended for electric haulage throughout? Yet whenever I see it pass, it is invariably hauled by a Class 66. I don't if that's because of a shortage of 88s, or because of the power supply north of Newcastle isn't up to the job.

When the Class 93 enters service, will it be rostered for this service and thereby go some way to reducing the number of diesels running under the wires?

Unless you know something we don't and ROG have won the Tesco and Russell contracts?

 

[Swanley 59]

The Mossend To Daventry train goes via the WCML and is 88-hauled, no?

I'm not sure if this a regular diversion, but it definitely ran via the ECML today; my garden looks out onto the line so I tend to notice whenever a freight passes!

Realtime Trains | 4Z48 1200 Mossend Euroterminal to Daventry Drs (Tesco) | 26/02/2023

Real-time train running information for 4Z48 1200 departure from Mossend Euroterminal to Daventry Drs (Tesco) on 26/02/2023. From Realtime Trains, an independent source of train running info for Great Britain.

www.realtimetrains.co.uk

Unless you know something don't and ROG have won the Tesco and Russell contracts?

No, I had it my head that it was DRS had ordered the Class 93

 

[Nicholas Lewis]

It more likely means the opposite.

What it does mean is that Government is going to have to fork out for quite a few power upgrades on existing electrified lines.

I guess you mean the firm capacity at feeder stations in some areas will be inadequate although given WCML could cope with a pair of 86's before any of it was fitted with ATF that should be adequate now its been upgraded as should ECML once the power upgrade at the North end has been commissioned. The GE has been partly reinforced and upgraded and a new supply point is being installed north of Chelmsford so that ought to cover most of the intermodal routes. GWR shouldn't need any upgrade.

The other thing to consider is if you are at a N-1 condition then the 93 could switch to diesel rather than have to spend vast amounts on increased power supplies or whilst you wait years to get one off NG.

 

[D365]

Unless you know something don't and ROG have won the Tesco and Russell contracts?

My thoughts indeed!

 

[Nottingham59]

if you are at a N-1 condition then the 93 could switch to diesel

Or any bimode passenger trains could do so, of course.

 

[43096]

The other thing to consider is if you are at a N-1 condition then the 93 could switch to diesel rather than have to spend vast amounts on increased power supplies or whilst you wait years to get one off NG.

There seem to be some amazing capabilities being claimed for these locos off-wires. With battery, they're a Type 3. Once the Duracells have gone flat, it's a Type 2. You don't want 1600t intermodals staggering along main lines being hauled by an asthmatic ant with heavy shopping.

 

[zwk500]

I'm not sure if this a regular diversion, but it definitely ran via the ECML today; my garden looks out onto the line so I tend to notice whenever a freight passes!

Realtime Trains | 4Z48 1200 Mossend Euroterminal to Daventry Drs (Tesco) | 26/02/2023

Real-time train running information for 4Z48 1200 departure from Mossend Euroterminal to Daventry Drs (Tesco) on 26/02/2023. From Realtime Trains, an independent source of train running info for Great Britain.

www.realtimetrains.co.uk

Definitely a diversion - that service is usually via Shap, not Chesterfield. It will have run with a diesel for the section from Doncaster to the WCML.

 

[Peter Sarf]

There seem to be some amazing capabilities being claimed for these locos off-wires. With battery, they're a Type 3. Once the Duracells have gone flat, it's a Type 2. You don't want 1600t intermodals staggering along main lines being hauled by an asthmatic ant with heavy shopping.

Gosh what a horrible thought, like having a single class 25 (i.e. type 2) on the front of a intermodal freight. Much better a 37 eh !.

 

[InOban]

Definitely a diversion - that service is usually via Shap, not Chesterfield. It will have run with a diesel for the section from Doncaster to the WCML.

I saw a picture which showed that it was double-headed by a 68/88 combo.

 

[zwk500]

I saw a picture which showed that it was double-headed by a 68/88 combo.

Sensible option from DRS - diesel for the non electrified but have the lecky ready. Ah, back to BR days with 47 drags!
The 88 of course also has its own power so could at least hold its own weight.

 

[ac6000cw]

Sensible option from DRS - diesel for the non electrified but have the lecky ready. Ah, back to BR days with 47 drags!
The 88 of course also has its own power so could at least hold its own weight.

The 68+88 combo is made easier because (based on my memory of what has been said on the forum) they can MU together, in diesel mode at least. I can't remember if a 68 can fully control an 88 in electric mode.

 

[zwk500]

The 68+88 combo is made easier because (based on my memory of what has been said on the forum) they can MU together, in diesel mode at least. I can't remember if a 68 can fully control an 88 in electric mode.

Yes, that's what I remember seeing as well. Hopefully interworking is kept by other orders as well.

It's notable that double heading is considered more efficient than changing locos at Doncaster and Bescot though.

 

[Nottingham59]

I can't remember if a 68 can fully control an 88 in electric mode.

Someone said that the 68s don't have a "pan up/down" control, so no. (If I remember correctly)