MML slow lines north of Bedford

[PeterY]

moderator note : posts #1 - #12 originally in this thread:

MML Electrification updates | RailUK Forums (railforums.co.uk)

Quick question. Next weekend I'm thinking of going to Corby. Do the 360's use the slow lines or fasts north of Bedford?

 

[Bald Rick]

Quick question. Next weekend I'm thinking of going to Corby. Do the 360's use the slow lines or fasts north of Bedford?

Yes!

(Both. Typically down trains use fasts to Kettering South Jn, up trains use the slows to Wellingboro’.)

 

[Yeetbuses2020]

up trains use the slows to Wellingboro’.)

Does that mean it is possible to get a passenger train through the previously freight only Sharnbrook tunnel?

 

[59CosG95]

Does that mean it is possible to get a passenger train through the previously freight only Sharnbrook tunnel?

Only if the main line over Sharnbrook summit is closed.

 

[edwin_m]

Does that mean it is possible to get a passenger train through the previously freight only Sharnbrook tunnel?

It's never been freight only in recent history (maybe before Leicester re-signalling). It's been certified for passenger use and used for diversions, and has been planned for use by the occasional service in various timetables over the years, usually a peak hour stopping train that gets overtaken by a fast.

 

[Spartacus]

I don't know why it's been thought it was a goods line, as far as I know it never has been, even when it was singled it was the Up & Down Slow. There's rarely been many booked to do it, I think currently the only WTT is the 2335 Saturday Only from St Pancras, though it's not unusual for other late night services to do it during engineering or if there's something running late for a 'stopper' to be run on the slows to let it past. There used to be an up passenger train booked to do it during the day but I'm sure that's now been lost with the various timetable changes.

 

[InTheEastMids]

I don't know why it's been thought it was a goods line, as far as I know it never has been, even when it was singled it was the Up & Down Slow. There's rarely been many booked to do it, I think currently the only WTT is the 2335 Saturday Only from St Pancras, though it's not unusual for other late night services to do it during engineering or if there's something running late for a 'stopper' to be run on the slows to let it past. There used to be an up passenger train booked to do it during the day but I'm sure that's now been lost with the various timetable changes.

Yes, it pre-Covid it was the 0730-ish from Derby, and was normally a short (ex GC) HST. I caught it on a couple of occasions. I think it varied where it crossed to the slow lines but always called at the short P3 at Wellingborough.

 

[richieb1971]

Yes, it pre-Covid it was the 0730-ish from Derby, and was normally a short (ex GC) HST. I caught it on a couple of occasions. I think it varied where it crossed to the slow lines but always called at the short P3 at Wellingborough.

It was class 222's in the end. It was only booked onto the slows as a fast not stopping at Bedford needed to overtake between Wellingborough and Bedford North junction. It went so slowly, slower than freight.

 

[edwin_m]

I don't know why it's been thought it was a goods line, as far as I know it never has been, even when it was singled it was the Up & Down Slow.

Not recently, but "never say never". Here's the diagram for Bedford North in about 1966, which shows the eastern pair going north as Goods lines.
Track Diagram: Bedford North (c1966) (signalbox.org)

Most of the MML was so designated when constructed, but parts were converted to passenger use (becoming Slow lines) over the years, particularly at the London end when commuting started to become more significant. Starting with West Hampstead in about 1980, progressive re-signallings have upgraded almost all Goods lines to passenger standard, but may in the Trent control area remained as Goods until the most recent re-signalling.

 

[Spartacus]

Not recently, but "never say never". Here's the diagram for Bedford North in about 1966, which shows the eastern pair going north as Goods lines.
Track Diagram: Bedford North (c1966) (signalbox.org)

Most of the MML was so designated when constructed, but parts were converted to passenger use (becoming Slow lines) over the years, particularly at the London end when commuting started to become more significant. Starting with West Hampstead in about 1980, progressive re-signallings have upgraded almost all Goods lines to passenger standard, but may in the Trent control area remained as Goods until the most recent re-signalling.

That's before my time! I wonder if it changed when Irchester South was abolished or the boxes around Wellingborough in 1987?

 

[richieb1971]

They are considered freight lines / goods lines because it was those trains that struggled to get over the hill and why the extra lines were built.

A banker used to sit on this siding. The slow lines are going under the arch on the left as the fast lines have already crept up 15 feet by this point.

 

[edwin_m]

They are considered freight lines / goods lines because it was those trains that struggled to get over the hill and why the extra lines were built.

Some may indeed consider them to be goods lines, and they were indeed built to easier gradients (but I think tighter curvature which would limit maximum speed). But in railway operating terms a Goods line is one which can't take passenger-carrying trains except under special arrangements. The Sharnbrook section hasn't been a Goods line since (probably) the Leicester re-signalling around 1987, nor are they "freight only" as suggested above.

 

[richieb1971]

Some may indeed consider them to be goods lines, and they were indeed built to easier gradients (but I think tighter curvature which would limit maximum speed). But in railway operating terms a Goods line is one which can't take passenger-carrying trains except under special arrangements. The Sharnbrook section hasn't been a Goods line since (probably) the Leicester re-signalling around 1987, nor are they "freight only" as suggested above.

I have no doubt passengers services can use the line. I've been through the tunnel on a charter train. I have photos of 222's coming out of the tunnel mouth.

But the sad fact remains that even though the lines are electrified the state of the track is terrible on the sections that were not improved. Most of it is jointed and the section passed Radwell can't have a speed limit over 50mph as everything crawls. So the electrification is not utilised that well in this area. Not as much as north of Wellingborough. I haven't checked lately, but does Oakley bridge have a 20mph speed limit on the up line still? I'm pretty sure it does. And that is not inter city quality service.

 

[DarloRich]

Most of it is jointed

wow - that IS a surprise!

 

[43066]

I haven't checked lately, but does Oakley bridge have a 20mph speed limit on the up line still?

It does indeed. I’m led to believe that’s down to structure clearance issues.

 

[43066]

Most of it is jointed and the section passed Radwell can't have a speed limit over 50mph as everything crawls.

That’s not the case for much (if any) of the track north of Bedford. Quite a bit of track has been renewed recently as part of the wider Sharnbrook resignalling. Speeds are however a lot slower than the fasts (50/70 versus 110/125.)

 

[Spartacus]

Yes, Oakley is still 20mph on the Up Slow, 50 on the Down Slow. Other than that between Wellingborough and Bedford it's a combination of 50 and 75.

 

[InTheEastMids]

I think the original idea may have been to make the slows 90mph from Bedford to Corby but then wasn't needed as EMR Connect services can fit in the fast lines and most of the freight is relatively slow moving aggregates. Hence little benefit in upgrading.

(Edit: i.e. the initial thinking was 90mph for the entire distance, whereas what's been delivered is 90mph from Wellingborough to Corby)

 

[ChrisC]

Returning to topic. I think the original idea may have been to make the slows 90mph from Bedford to Corby but then wasn't needed as EMR Connect services can fit in the fast lines and most of the freight is relatively slow moving aggregates. Hence little benefit in upgrading.
(Edit: i.e. the initial thinking was 90mph for the entire distance, whereas what's been delivered is 90mph from Wellingborough to Corby)

How many electrically powered trains are actually going to be using the slow lines through Sharnbrook Tunnel? If no regular passenger trains are using it are there going to be any electric freight locos using it?

I’ve heard the reasons why it was electrified to enable full flexibility for whenever the fast lines are blocked but it must have cost a very significant amount of money to electrify the line through the tunnel. There was also quite a number of other structures like bridges that lots of money was spent on. I may be missing something here but would the money spent, and even electrifying Kettering to Corby, have been better used electrifying north to at least Leicester?

 

[Ianno87]

How many electrically powered trains are actually going to be using the slow lines through Sharnbrook Tunnel? If no regular passenger trains are using it are there going to be any electric freight locos using it?

Until the wires stretch somewhere useful north of Market Harborough - None.

Hopefully the wires themselves at least passively provide for a future Slow Line speed upgrade.

 

[JonathanH]

I may be missing something here but would the money spent, and even electrifying Kettering to Corby, have been better used electrifying north to at least Leicester?

Electrifying four lines in a given location is surely cheaper than two lines for a longer distance given that some of the costs are feeder stations.

What would happen during engineering work if the slow lines aren't electrified? Would they simply not run the Corby services?

 

[gaillark]

What would happen during engineering work if the slow lines aren't electrified? Would they simply not run the Corby services?

That's easy in the modern railway era: Everything is a Bus replacement and somethimes with a good planner run with diesel services.

 

[Ianno87]

and somethimes with a good planner run with diesel services.

Unfortunately with Corby services that would mean reducing Nottingham/Sheffield to free up the stock needed.

 

[OxtedL]

Unfortunately with Corby services that would mean reducing Nottingham/Sheffield to free up the stock needed.

Presumably service reductions used to happen anyway when slow line running occurred pre-upgrade

 

[alf]

What’s the reason for the 20mph PSR on the Oakley up slow?
Presumably it’s not alignment as the down slow is 50mph.

Can it be raised to 50 or more at reasonable cost?
It imposes extra fuel costs on heavy stone traffic.
I reckon between 5 & 10 litres per 1,000 ton train passage, a back of envelope guess.
And there is the increase in journey time & extra diesel particulates.

 

[Western Sunset]

Back in the day, the Goods Lines extended from Bedford South, via Sharnbrook, to Kettering Junction.

 

[RT4038]

Back in the day, the Goods Lines extended from Bedford South, via Sharnbrook, to Kettering Junction.

Can this be right? I thought passenger trains crossed over from the fast (passenger) lines at Kempston Road Junction, though Midland Road Station and recrossed to the fast (passenger) lines at Bedford North? Didn't the Goods Lines recommence at Bedford North to Kettering Junction?

 

[Western Sunset]

Sorry, I meant to type Bedford North...

Old age moment.

 

[JonathanH]

Presumably service reductions used to happen anyway when slow line running occurred pre-upgrade

Well yes, and tedious waits for the flighting on the single line section but they have put back in two lines now so it should be better in the future.

 

[zwk500]

What’s the reason for the 20mph PSR on the Oakley up slow?
Presumably it’s not alignment as the down slow is 50mph.

Can it be raised to 50 or more at reasonable cost?
It imposes extra fuel costs on heavy stone traffic.
I reckon between 5 & 10 litres per 1,000 ton train passage, a back of envelope guess.
And there is the increase in journey time & extra diesel particulates.

It might be something to do with the structure, on aerial photos the parapet adjacent to the Up Slow looks to be definitely more dodgy than the others. If it is this, it will cost a lot to fix.