Possible future Southeastern HS1 fleet

[brad465]

The 395s are nowhere near the end of life, being 17 years into service and having just had a mid-life interior refurb. However, there are arguably not enough of them to manage demand, which recently hasn't been helped by the Ramsgate derailment unit repair. I'm not aware of the service's exact profitability, but a HS1 premium charge combined with most services being well-used shows it must be viable and have potential that more capacity would unlock.

Would Southeastern benefit from ordering a new fleet to expand on the existing one and provide a platform for the eventual 395 replacement at end of life? Depending on the timings, a new effective microfleet would be made first to enhance capacity, then a larger follow-up order of the same class would seek to replace the 395s when due.

I was thinking a fleet of high-speed BEMUs might be worth looking at, which use OHLE on HS1 but then off HS1 use battery power and/or third rail, the batteries providing extra power to support third rail (395s on third rail are more sluggish than 375s), which might also allow for higher top speeds on HS1 (and be easier to path around Eurostars). Batteries would also of course allow for the prospect of Hastings' services if the physical connection necessary at Ashford were ever made.

Of course in reality Southeastern are trying to get their metro fleet replacement order through right now, so any HS1 order will not happen until this is sorted, and/or a very strong irresistible business case is produced.

 

[HSTEd]

I think a modern Class 395 supplement or potential replacement would potentially be a very good idea, but obviously the fleet expansion would probably be limited by the capacity at St Pancras.

How many more trains could you realistically run before you need additional platforms?

 

[Farigiraf]

Batteries would also of course allow for the prospect of Hastings' services if the physical connection necessary at Ashford were ever made.

This is really the only benefit of BEMUs for Southeastern, but realistically how likely is such a service actually? You'd need to do some costly upgrades to the Marshlink line, and journey times from London to Hastings/Ore wouldn't be massively faster than Southeastern, meaning that not many people will pay the HS1 fare. The idea of HS1 to Hastings being a cheap, easy win as long as some BEMUs are acquired is a bit of a myth. Upgrading the Marshlink line is a good idea, but it makes more sense as a separate project with more East Coastway integration (e.g. through services to Brighton) since Southern will eventually have to get some BEMUs anyway.

As for SE High Speed as a whole, I can't think of many improvements that are really worth it. Frequencies are already great - 1tph to most towns (2tph at peaks) plus local stopping services is really the limit of what you can easily run - and speeds are obviously quite high (the classic lines through Dover/Canterbury are rather slow but I can't see how you could justify the cost of linespeed increases) so the only thing you could really improve upon is capacity. 8-car trains over the current 6-cars makes the most sense, but I don't know how you'd fit these in at stations like Martin Mill.

Realistically the best use of the surplus capacity on HS1 is always going to be more international trains, not just from a revenue perspective.

 

[HSTEd]

In terms of line capacity, I think international trains could double and still not be a significant load in terms of paths. You could never justify enough international paths to fill the line even if the capacity existed at St Pancras customs.

 

[Peter Mugridge]

In theory you could replace the 395s on South Eastern with an IET based fleet and then use the 395s, with their ability to accelerate and brake quickly, to provide an hourly all stations service between Edinburgh and Newcastle, slotted in between the longer distance services and then extended to Glasgow Queen Street - again all stations as an extended part of the shuttle service although that would not require use of the entire fleet.

Rough calculation, based on hourly, that would only require 8 or 9 diagrams, so about a third of the fleet including maintenance cover?

Trying to keep the fleet together in the one area on top of that would highly likely end up being a solution looking for a problem...

 

[Mikey C]

The 395 fleet only needs to be slightly larger, so that more services can run as 12 car, and there's a bit more slack. But the economics of building another 4 units obviously doesn't add up.

 

[HSTEd]

The 395 fleet only needs to be slightly larger, so that more services can run as 12 car, and there's a bit more slack. But the economics of building another 4 units obviously doesn't add up.

With the advances in power electronics over the last 20 years, its probably possible to use the same sorts of equipment on the N700S to build a 300km/h train that still accelerates like the Class 395. A 6-car N700S (admittedly 150m long, not 120m but still) appears to have 24 ~305kW traction motors for 7,320kW. A 240m train could end up with almost as much power as a 400m Class 374.

If traffic on HS1 really expands (by somehow overcoming the terminal limits), having trains that can go faster might be useful from a pathing perspective.

It'd be interesting to model what a Class 395 would behave like on say the West Coast Main line in place of the 110mph non Avanti services. You could buy a new faster fleet for HS1 and send the Javelins there.

But in the short term, can't see much of a driver to do more given the limitations on train numbers.

 

[brad465]

I think a modern Class 395 supplement or potential replacement would potentially be a very good idea, but obviously the fleet expansion would probably be limited by the capacity at St Pancras.

How many more trains could you realistically run before you need additional platforms?

Off-peak two platforms is currently enough. In the peak turnaround times for each train appear to be 12-17 minutes, so from this point it might be possible to squeeze an additional 1tph in towards Ashford, providing 3tph between Ashford and St Pancras. If the necessary work to send this to Hastings were made, this would be the ultimate destination, but if not maybe a Canterbury West/Margate and Dover split to increase each route to 2tph for HS1 services.

There may also be some capacity increase in some of a future fleet being fixed 12-car formations, which would add more space in the equivalent area covered by two driving cabs and two nose-cones in a 395 12-car formation. These would also add capacity to Folkestone and Dover by presumably being cleared through Shakespeare tunnel (currently 12-cars are not permitted in passenger service unless the rear unit is locked out of use). However, the whole fleet couldn't be 12-car if the Maidstone West extension is to be retained, if some splitting/joining services were to be offered, and especially a Hastings' extension that probably can't take 12-car at Rye due to fouling level crossings and/or the loop pointwork (unless this area is to be fully redoubled in this hypothesis).

 

[Cach17]

The Kent Rail Strategy from 2021 suggested a new fleet of up to 14 Class 80X trains for SE to expand their HS services (mentioned on page 30 of the linked document). Like other plans in it though, I can't really see anything big happening until the 395s reach retirement age.

 

[Mikey C]

The 395 fleet only needs to be slightly larger, so that more services can run as 12 car, and there's a bit more slack. But the economics of building another 4 units obviously doesn't add up.

Yesterday for example, I was on a Ramsgate via the Medway Towns service, 6 cars in both directions, and it was really busy. The sort of Saturday seaside service where I'm sure longer trains would be used if the stock was available.

 

[NCT]

A top-up fleet probably won't happen as it would have to be a bespoke micro-fleet order. A piggy-back order of Class 80x won't happen as the Kent route can only handle 20-metre carriages. SE also needs 1/3 2/3 door positions.

Timetabling isn't a problem as there are 8 notional domestic paths per hour on HS1.

 

[brad465]

A top-up fleet probably won't happen as it would have to be a bespoke micro-fleet order. A piggy-back order of Class 80x won't happen as the Kent route can only handle 20-metre carriages. SE also needs 1/3 2/3 door positions.

Timetabling isn't a problem as there are 8 notional domestic paths per hour on HS1.

This is why I suggested do an initial order of a new fleet type, but then keep the design for a larger order to replace the 395s.

 

[NCT]

This is why I suggested do an initial order of a new fleet type, but then keep the design for a larger order to replace the 395s.

I doubt either the buyer or seller would want to tie themselves into an order that wouldn’t be exercised for 15 years. No, there’s no avoiding the cost of a micro order and that’s why it wouldn’t happen.

 

[brad465]

I doubt either the buyer or seller would want to tie themselves into an order that wouldn’t be exercised for 15 years. No, there’s no avoiding the cost of a micro order and that’s why it wouldn’t happen.

Wouldn't be unprecedented though; Virgin received another 4x 390s a good 5-7 years after the last of the first batch, while TPE decided 12x 397s was enough. Then even more recently LNER ordered 10x 897s.

 

[Peter Mugridge]

Wouldn't be unprecedented though; Virgin received another 4x 390s a good 5-7 years after the last of the first batch, while TPE decided 12x 397s was enough. Then even more recently LNER ordered 10x 897s.

In the case of the extra 390s, that was bundled in with a fairly substantial order for additional intermediate carriages for most of the rest of the fleet, so not really a small order - and also not creating a small separate fleet either.

Good point on the 397s and 897s, I agree ( and word is the 897s was because it was the cheaper option despite creating the obvious microfleet headache ).

 

[renegademaster]

The way HS1 is used wouldn't a Thameslink style open gangway pack em in train make more sense than a IET variant

 

[Cach17]

The way HS1 is used wouldn't a Thameslink style open gangway pack em in train make more sense than a IET variant

Dunno about open gangways, but I could foresee a 395 replacement having a fixed 12-car variant, a la the 700s. Such units would certainly come in handy for the Shakespeare Cliff Tunnel near Dover where the rear unit of a 12-car 395 formation has to be locked out of use due to tight clearances and the lack of end gangways.

 

[Sorcerer]

Would it be possible to have a fleet of trains that can reach 300km/h on HS1 to help reduce capacity constraints in light of increasing international traffic? Or would the requirement for third rail compatibility throw a spanner in those works with an already expensive bespoke fleet? Between St Pancras and Ebbsfleet I can't see much issue since the max line speed there is 230km/h.

 

[Mikey C]

In the case of the extra 390s, that was bundled in with a fairly substantial order for additional intermediate carriages for most of the rest of the fleet, so not really a small order - and also not creating a small separate fleet either.

Good point on the 397s and 897s, I agree ( and word is the 897s was because it was the cheaper option despite creating the obvious microfleet headache ).

I don't know what size order would be needed to make such an order economic for the manufacturer. Another top up order, years after the original, was the extra carriages (and 4 additional trains) for the 1996 tube stock.

I do find the 395s impressive trains. They might be in the same family as the IETs, but are very different though.

 

[brad465]

Would it be possible to have a fleet of trains that can reach 300km/h on HS1 to help reduce capacity constraints in light of increasing international traffic? Or would the requirement for third rail compatibility throw a spanner in those works with an already expensive bespoke fleet? Between St Pancras and Ebbsfleet I can't see much issue since the max line speed there is 230km/h.

The 373s were able to have third rail capability on top of a 300km/h top speed so it must be possible.

I don't know what size order would be needed to make such an order economic for the manufacturer. Another top up order, years after the original, was the extra carriages (and 4 additional trains) for the 1996 tube stock.

I do find the 395s impressive trains. They might be in the same family as the IETs, but are very different though.

Ordering a few units to top-up the existing fleet and nothing more probably isn't viable. If a new route/higher service frequency was added then more units being required might make it more viable. If a Hastings' service proved viable then this would be the natural option, however of course with this you have to do work at Ashford and along the Marshlink line on top.

 

[Sorcerer]

The 373s were able to have third rail capability on top of a 300km/h top speed so it must be possible.

I forgot about that, but now the answer does seem to be a yes. I suppose the new question is whether or not they will be as power-hungry as the old 373s. It might be a bespoke design but I'm sure some manufacturers could probably create a more energy efficient dual-voltage unit if the 395 replacements were specified for 300km/h capability, which I personally think they should be.

 

[marshlinker]

I think you need to look at the passenger flows to determine where you need extra trains.
The major country stations on the high speed services are Ashford and Canterbury West.
If you have 12 coach trains to Dover they probably don't need to travel beyond Ashford and certainly not beyond Folkestone.
Thanet services need 12 coaches in Summer as the demand is very seasonable, not beyond Ashford in Winter.
Most 12 x 395 trains already join/detach at Ashford. Its a very slick operation.
Roughly passenger entries/ exits work out (all services)
Dover 1.2 million
Folkestone West & Central 1 million each
Margate & Ramsgate 1.2 m each
Canterbury West 2.7m
Rye (Marshlink) 0.48m
Ashford Int. 3.7m

 

[Mikey C]

Would it be possible to have a fleet of trains that can reach 300km/h on HS1 to help reduce capacity constraints in light of increasing international traffic? Or would the requirement for third rail compatibility throw a spanner in those works with an already expensive bespoke fleet? Between St Pancras and Ebbsfleet I can't see much issue since the max line speed there is 230km/h.

As all domestic trains stop at Ebbsfleet and Ashford, a domestic 300km/h train would only reach top speed for a relatively short journey anyway.

 

[marshlinker]

The 373s were able to have third rail capability on top of a 300km/h top speed so it must be possible.

They could only run on the channel tunnel enhanced dc system; North pole/ Waterloo Int to Continental Junction (Channel Tunnel) via Tonbridge and Maidstone East and also to Fawkenhan Junction.

 

[Cach17]

As all domestic trains stop at Ebbsfleet and Ashford, a domestic 300km/h train would only reach top speed for a relatively short journey anyway.

Checking RTT, two peak hour Margate-STP services in each direction pass through Ebbsfleet non-stop, but you're right about Stratford.

 

[brad465]

As all domestic trains stop at Ebbsfleet and Ashford, a domestic 300km/h train would only reach top speed for a relatively short journey anyway.

Checking RTT, two peak hour Margate-STP services in each direction pass through Ebbsfleet non-stop, but you're right about Stratford.

300km/h is probably excessive, but 270km/h maybe achievable, especially if able to utilise a higher hp than 395s. A higher top speed would be more about pathing alongside Eurostars/international services than reducing journey times. If a future fleet came with batteries this could not only help should a Marshlink service ever happen, but could provide additional power alongside third rail to accelerate faster; 395s are apparently inferior to 375s on third rail, which is particularly notable between Ashford and Sandling, where 100mph running is possible.

 

[Sorcerer]

As all domestic trains stop at Ebbsfleet and Ashford, a domestic 300km/h train would only reach top speed for a relatively short journey anyway.

300km/h is probably excessive, but 270km/h maybe achievable, especially if able to utilise a higher hp than 395s. A higher top speed would be more about pathing alongside Eurostars/international services than reducing journey times.

This very much is the case to what I'm suggesting. At present HS1 could probably still manage the mixed speeds but if Virgin and Trenitalia are looking at running trains on the international market then you'll have more trains running at 300km/h that could be slowed down by 230km/h units running domestic high-speed commuter links. I was thinking more about maximising line capacity than simply gaining a few extra minutes of journey time.

 

[ScotGG]

Let's say Ebbsfleet is built out as planned over the next decade. Is the HS1 stock sufficient for that increase in passengers?

 

[HSTEd]

As all domestic trains stop at Ebbsfleet and Ashford, a domestic 300km/h train would only reach top speed for a relatively short journey anyway.

The 57km run from Ebbsfleet to Ashford should easily allow a modern high performance unit to reach 300km/h.

If you used N700S tech, a 240m train could potentially pack in almost as many horsepower as a Class 374.

It only has to save a minute or two before it starts to impact pathing.

You could buy new trains and send the 395s to the West Coast or East Coast main lines for suburban duties.

 

[marshlinker]

300km/h is probably excessive, but 270km/h maybe achievable, especially if able to utilise a higher hp than 395s. A higher top speed would be more about pathing alongside Eurostars/international services than reducing journey times. If a future fleet came with batteries this could not only help should a Marshlink service ever happen, but could provide additional power alongside third rail to accelerate faster; 395s are apparently inferior to 375s on third rail, which is particularly notable between Ashford and Sandling, where 100mph running is possible.

Don't think this is actually true. An up 6 car 395 starting from Folkestone West can reach 100mph by the French Interconnector at Sellinge which is much the same as a 375 and will then continue about the line limit until the Ashford Orbital Road Bridge. A Down 395 seems much slower starting off from Ashford because it has to cross the ladder from platform 5/6 to gain the Dover Road.
I think a lot of it is due to timetabling.
Having said that 375s on the enhanced DC are noticeably quicker than they are elsewhere. An Up 12 car 375 from a stop at Sevenoaks will hit 80 mph by the portal of Polhill Tunnel which is only about 4 miles.