Hitchin flyover

[jopsuk]

the Cambridge News has a video of the plan for the new flyover at Hitchin, to relieve the current flat junction between the ECMl and the Cambridge line. Looking at it, the route would appear to be something thus?

Wonder what sort of linespeed they're aiming for? After all, there's 2 non-stop Cambridge trains an hour pass through Hitchin.

 

[Metroland]

The full linespeed of the Cambridge line I think (about 75mph). One of the big problems with the railways in this country is most junctions tend to be built on the flat - with a couple of notable exceptions such as Weaver Junction which was a very early grade separated alignment.

Grade separation never really got into fashion during the big rail building period, and only started appearing with some of the later lines, such as the Aynho-Princes Risborough line, Great Central and modifications made to GWR lines in the 1930s, such as the Berks and Hants.

This isn't the case in Europe, especially Germany, where most junctions seem to be grade separated. Nor is it the case for motorways and major truck roads which tended to be built from the 1950s onwards. This is why our railways have so many pinch points, we could run a lot more trains (on time) with just a few grade separation improvements - such as Hitchin, Reading etc. But they work best with a high line speed coming off the main line.

 

[bluenoxid]

Well somebody didn't bomb us to bits like we did to the rest of Europe, particularly Germany. Over 100 years of experience went into developing the technology and expertise for rebuilding the European network so they were bound to get quite a bit of it right.

I don't know what sort of linespeed they are aiming for but it will be a trade off between cost and hogging space.

 

[Edvid]

I read somewhere (sorry can't remember where) that the flyover linespeed would be 60mph, adding 1 minute to a down London King's Cross-Cambridge service.

 

[bluenoxid]

I hope FCC suitably negotiate their contract to take this mass and deliberate delay into account. They are going to need as much as they can especially if it saves 18,000 minutes

 

[ungreat]

The full linespeed of the Cambridge line I think (about 75mph)

90 mph is the max linespeed on the Cambs line.Current Down fast junction at Hitchin to go to Cambs is a 40 mph crossing.

Cambs line varies between 50-90 mph,depending on level crossings and track alignment

 

[yorkie]

I read somewhere (sorry can't remember where) that the flyover linespeed would be 60mph, adding 1 minute to a down London King's Cross-Cambridge service.

how would that add time if it´s 20mph faster than at present?! it might subtract a minute.

 

[Edvid]

Yes, if the flyover is built along exactly or close to the same alignment as the flat crossing. AIUI the flyover alignment is such that even at higher speed there is sufficient additional mileage to add time to such a journey.

 

[shinkansen09]

I read somewhere (sorry can't remember where) that the flyover linespeed would be 60mph, adding 1 minute to a down London King's Cross-Cambridge service.

How can a new flyover add 1 minute to a down line service when the speed is higher(?) than at present? Is it because the new flyover is situated further north?
On a brighter side its about time this bottleneck was removed.....or should i say relocated :roll:

 

[bluenoxid]

How can a new flyover add 1 minute to a down line service when the speed is higher(?) than at present? Is it because the new flyover is situated further north?
On a brighter side its about time this bottleneck was removed.....or should i say relocated :roll:

Read Edvid's post and watch the video. The bridge swings quite a bit to get the right angle to cross the ECML.

However, I do wonder if it actually will because I'm pretty sure that Hitchin gets pathing time for the trains so the net effect will be zero by the time that is removed (because the trains don't have the risk of being delayed crossing the ECML and it encompasses any additional time to rise over the track.

 

[jopsuk]

Read Edvid's post and watch the video. The bridge swings quite a bit to get the right angle to cross the ECML.

However, I do wonder if it actually will because I'm pretty sure that Hitchin gets pathing time for the trains so the net effect will be zero by the time that is removed (because the trains don't have the risk of being delayed crossing the ECML and it encompasses any additional time to rise over the track.

The benifit, though, isn't really for Cambridge trains, but for trains to the North (ie NXEC, GC and HT) which can be retimtabled without having to take northbound Cambridge line services crossing both the fast lines into account. A minute or so either way won't make any odds to the Cambridge trains.

 

[bluenoxid]

The benefits will affect both routes. I am sure that quite regularly Letchworths and the 365's are brought to a halt by late running Intercity's and vice versa. What I was talking about was that the timetabling people will be able to offset any gain in travel time from the pathing allowance that the trains will probably get for Hitchin (although I am not sure of this and someone else will need to read the Rules of the Route to confirm or deny.

Those minutes do start to count especially with late running and also getting services through Welwyn.

 

[DaveNewcastle]

The benefits will affect both routes.

Yes, especially main-line UP and Cambridge down, neither of which will now require a long sterile period while traffic in the opposing direction crosses them.

And it also helps keep the freight moving - which as we all know gets held up all over the network. Its "little" improvements like this that contribute to releiving the some of the massive consequential delays that can so easily mount up after a minor issue arises.
Excellent news, I reckon!

 

[A60K]

Well somebody didn't bomb us to bits like we did to the rest of Europe, particularly Germany.

What crap. Take a history lesson.

 

[The Planner]

What I was talking about was that the timetabling people will be able to offset any gain in travel time from the pathing allowance that the trains will probably get for Hitchin (although I am not sure of this and someone else will need to read the Rules of the Route to confirm or deny.

Those minutes do start to count especially with late running and also getting services through Welwyn.

I expect you mean the Rules of the Plan, and pathing allowance isnt part of that. Pathing allowance is purely to keep a headway or junction margin if you are too close to the established values. There is a 1 mnute adjustment to sectional running times for trains crossing over to Cambridge due to the approach control signals and the speed difference. Depending on the layout, that wont neccesarily dissapear.

 

[bluenoxid]

What crap. Take a history lesson.

I did thanks. Whilst the Germans scored some notable successes during the Blitz, they failed to bring our rail network to a crunching halt.

We bombed the Germans many times over compared to them bombing us. In just four years, our bombers were capable of delivering much more bang per bomber than the Germans were ever capable of delivering to us. We talk about Coventry and London but that was NOTHING compared to Dresden which was a firestorm for days. We ripped the Germans apart with very few buildings left standing in their cities. Yet many of our old buildings in cities remain.
--- old post above --- --- new post below ---

I expect you mean the Rules of the Plan, and pathing allowance isnt part of that. Pathing allowance is purely to keep a headway or junction margin if you are too close to the established values. There is a 1 mnute adjustment to sectional running times for trains crossing over to Cambridge due to the approach control signals and the speed difference. Depending on the layout, that wont neccesarily dissapear.

Ah right. I thought it was.

 

[A60K]

Read my quote and you'll see what of your post I object to. Yes, Germany bombed Britain and Britain bombed Germany - that's not in question, and much of the bombing on both sides was of limited military effectiveness. The British had the dubious honour of developing the 'best' strategy later in WWII, and killed many more people in bombing raids in Germany than v.v., but don't think for a moment that the Germans weren't trying to do the same.

But for you to claim that 'we bombed the rest of Europe to bits' is complete nonsense. Take a look at this list of cities and see how much of the bombing in Europe was British action and how much by other countries: Warsaw, Caen, Wielun, Dublin, Leningrad, Rotterdam, Belgrade, Chisinau, Gibraltar, Helsinki, Sofia, Tallinn, Budapest, Frampol, Zadar, Stalingrad, Frascati, Bucharest. It's nothing like the simplistic assessment you present as fact.

And getting back on the subject, while there was a certain amount of grade-separation after wartime damage in Germany, the vast majority of this work was done as part of normal peacetime capital investment.

In Britain the LSWR recognised the benefits very early on, and there are a number of examples on other British railways, and the same on the Continent. A lot of railways were built to the lowest possible budget though, with flat junctions and poor alignments.

Grade-separation has been happening for over 100 years both here and in the rest of Europe, and when and where it occurs is largely down to how much national governments value and provide financial assistance to their railways.

The Swiss are one of the most pro-rail nations, and you see the benefits travelling around their network. Many conflicts eliminated or in planning with dive-unders, additional platforms, tunnels, new lines, fly-overs, junction rebuildings, underground platforms at existing stations. None of that is as a result of wartime repairs, all is down to how much the Swiss value their railways and are willing to invest. Curiously though, many of their train toilets still open directly on to the track, both solid and liquid matter falling straight through a hole!

 

[broodje]

That is the same for the dutch network (on both accounts) I can't think of many non-grade separated JNs, other then at stations (but even then, Rotterdam, Utrecht, Amsterdam and more all have multiple fly-overs).
In the Netherlands only few fly-overs were build before the 50sh. Admittedly until halfway the 50sh much of the dutch railways had to be rebuild due to bombings by the allied and raids by the German (especially bridges were bombed), but after that lots of fly-overs have been build. I think most of them were build around the 90sh.
The Swiss don't have that many grade separated jns but that is not that strange, due to the nature of the landscape and underground it is very difficult to do so.

Oh, and yes the dutch also ditch their toilets contents trough a hole in the carriage you really don;t want to know how the underside of a carriage looks like after a few weeks.

 

[Metroland]

The other thing continental railways have a lot of is bi-directional signalling. I remember taking an express from Paris to Stuttgart. before TGV Est was open, on a 16 coach plus coach train, front half was German coaches, back French Co-rails. On at least one occasion we switched to the opposite running line, overtook some freight, and then back again a few miles later, all at 'normal' speed.

They also seem to go round curves faster (lower centre of gravity?).

Anyway, grab yourself an Interail pass and go and have a look, you will be shocked how 'massive' the station layouts, fly-overs, trains etc are. On German secondary lines they seem to have 8 coach double decked trains, on similar lines here you would have 3 car 158s! Any idiot can work out why we have 'capacity' problems and a certain amount of unreliability in the UK, especially as its so densely populated and mixed traffic.

 

[philjo]

The benefits will affect both routes. I am sure that quite regularly Letchworths and the 365's are brought to a halt by late running Intercity's and vice versa.

We waited at Hitchin for 7 minutes the other night waiting for clearance to cross the junction towards Letchworth
2 NXEC nothbound trains, one each of NXEC & HT & FCC stopper service runing southbound plus a Class 91 running light on up slow all came though whilst we were waiting.
I think we had missed our slot as arrived at Hitchin 2 minutes late & I think the southbound NXEC was late too as I usually see that train in the platform at Stevenage

The route by the new flyover is further than the existing route, hence the 1 minute time difference, but should be compensated by not having to wait at Hitchin for a signal to cross the junction.


There is a lot of correspondance in the local press at the moment over the number of lorries required in conjucntion with the flyover works - it seems that they will all be routed via a temporary road link to the edge of Letchworth & then via Stotfold A507 & A1.

http://www.thecomet.net/search/stor...7:06:21:000&tBrand=CMTOnline&tCategory=search

Any reason why they can't transport some of the materials by rail to Hitchin yard?

 

[A0wen]

]

Any reason why they can't transport some of the materials by rail to Hitchin yard?

I'd be guessing cost, availability of slots on the ECML (which are already at a premium) and convenience, because they'll want to get the materials to the site, which if I understand it correctly is about a mile further up the line from Hitchin yard.

 

[philjo]

This item is on BBC news today:

http://news.bbc.co.uk/1/hi/england/8282089.stm

 

[philjo]

Front page news in the local paper this week:

http://www.thecomet.net/news/plans_for_hitchin_flyover_given_secretary_of_state_approval_1_686959

CONTROVERSIAL plans to build a new rail flyover just north of Hitchin were given the go ahead by the secretary of state for transport yesterday (Wednesday).

The ongoing proposals, which aim to improve rail services, have caused concern amongst some residents, who claim that vehicles delivering building materials to the site may cause traffic congestion and take over residential areas.

A report by the inspector highlighted that the preferred route between the construction site and the A1 and A1(M) would be via Stotfold road, Wilbury Hills road and the A507.

But it was noted that if this route was used, the Wilbury Hills road would have to be widened, either on a temporary or permanent basis.

“It’s definitely going to cause trouble, and if anything there’s going to be a death” said Alan Hinchliffe, who is the chairman of the Hillcrest Park resident association.

“We don’t want the road widened, it’s already a race track, and we can hear cars racing round. If it is widened, then more heavy goods vehicles will use it as an alternative route.

“One of the reasons I moved here was because it was away from the traffic and noise.”

The secretary of state concedes in the report that there would be a number of adverse impacts on local residents, businesses and the environment.

But these are described as “limited” and would be “outweighed by the benefits of the scheme.”

Some recommendations in the report still need to be approved, which may take some months.

The flyover would accommodate trains on the East Coast main line between Hitchin and Cambridge, and will cost in the region of £62 million to build.

It seems to be saying this as a bad news story. Obviously there will be disruption whilst it is built due to the lorry movements.

 

[jopsuk]

Inevitably such a scheme will be disliked by locals- after all, it doesn't actually bring any benefit directly to local people- but does mean, for the duration of the work, some disruption. They suffer for the "greater good"- but not everyone thinks of others.

 

[YorkshireBear]

"if anything there’s going to be a death"

yeah if you drive unsafely there will be death your right, answer? drive safely.

This project is fantastic and is what should be happening around the country it's not a huge project but it makes huge improvements.

How much capacity will it release?

 

[jopsuk]

Off peak, there's four Kings Cross-Cambridge trains and a Moorgate- Letchworth train that have to cross the Up lines- and services that call at Hitchin have to cross the Down Fast as well.

 

[LE Greys]

The thing people are making the most fuss about is the construction traffic. It seems that they don't appreciate that this will be for a limited time and produce a genuine improvement at the end of the day. Personally, I think it would be be better if most construction material came in by rail and was moved alongside the line (separated by a temporary fence) into position. There must be a few spare freight paths at night that could be used for this, and there are still a few useful sidings in the old yard north of the station. However, even if it does come in by road, I've been held up north of Cambridge Junction too many times, so it's a price worth paying.

 

[jopsuk]

I'm not trying to excuse the petty, small minded, short-termist attitude of those theat complain, but I can see thir point of view- it's a price they have to pay, but they aren't the ones that are held up on the railway line!

 

[tbtc]

Off peak, there's four Kings Cross-Cambridge trains and a Moorgate- Letchworth train that have to cross the Up lines- and services that call at Hitchin have to cross the Down Fast as well.

...so potentially five additional paths northbound on that stretch?

(I know Welwyn will stop most capacity in that neck of the woods, but its good to have a figure)

 

[jopsuk]

It is the southbound paths that are most affected- the northbound paths will still be needed by those trains. The two Cambridge Express services will need to cross the Down Slow to reach the flyover- at the moment, the slow Cambridge and Letchworth services have to cross the the Down Fast. But the biggest improvement is no longer having northbound trains crossing the southbound lines.