Southern Region banned stock

[Robin Brasher]

A First Great Western high speed train with power cars 43 078 and 43 028 on the Cotswold to Purbeck Express from Worcester on 28 September 2013 terminated at Corfe Castle due to gauging issues. Please see report in Comings and Goings by George Moon on page 25 of the Spring 2014 issue of Swanage Railway Magazine. I think that it was due to the platform clearance at Swanage Station.

[PaulRhB]

As mentioned above on mk3's short links are now the norm but they do still have width restrictions on tight curves. Salisbury Tunnel Jn to Laverstock South has an OPPOS restriction where the opposite line must be clear and according to the track engineer it is definitely needed. Hence the NMT runs as 1X23 between Salisbury and Southampton. It's even been written into the WTT as such now after a 3 yr 'discussion' with train planning

The occasional football specials FGW have run also had to be 1X headcodes on that section.

[Gwiwer]

Salisbury Tunnel Junction is a particularly tight curve on the Southampton line which arises from the creation - at an early date - of the link line from an original terminus at Milford to the main Salisbury station.  The curve at Milford is less severe, leads to a short straight high above the delightfully-named Wain-a-Long Road and into the tight left-hander into the tunnel.  Geography ensured there was no other option here.  As the route is used by hourly Portsmouth - Cardiff and hourly Salisbury - Southampton - Romsey workings all formed of class 158 units (meaning there are at least four moves per hour of this stock around the curve) do they also have a restriction applied or is their body profile considered to be acceptable through the Tunnel Junction curve?

 

23-metre stock does not normally reach Littlehampton but I would be very sure a similar restriction applies on the tight curve between Arundel Junction and Littlehampton Junction.  And also elsewhere as there remain numerous similarly sharp curves on the SR as part of (or which were part of) triangles.  Dover Priory - Martin Mill includes another at Kearsney.

[Edwin_m]

It would be interesting to know exactly how many places on the Southern (and elsewhere) are incompatible with 23m stock, and whether many of these could be eased without too much dificulty if someone had a reason to do so.  I suspect there are actually rather few, though some of them might be difficult to sort, but that nobody has really asked the question so the usual inertia of the railway industry ensures that nothing changes. 

[Gwiwer]

Northam took a fair bit of work but had to be done.  At the time there was clearly less urgency to deal with Salisbury Tunnel Junction which also still had a working signal box preventing the curve being eased.  If it mattered the curve could potentially be eased there now.   Cosham - Farlington Junctions is another sharp curve used by 23m class 158 / 159 units without modification but whether "standard" Mk3 profile vehicles are allowed is a valid question.  The curve at Fareham was effectively eased many years ago when the bridge was rebuilt.  While it's still extremely tight it isn't adjacent to the opposite line meaning clearance should not be an issue there.

[pete_mcfarlane]

I know of no locomotive restrictions over SR electrified routes caused by the presence of the conductor rails.  The only restrictions are (or were) occasioned by the Restriction 0 (Mountfield) and Restriction 1 (Groombridge) "narrow" routes and specific weight limits.

IIRC class 10 and other similar English Electric shunters with 4' wheels were banned from 3/4 rail electrified areas because of the clearances between their outside coupling rods and the 3rd rail. This mainly concerned the North London DC lines, but would have also stopped them being used on the Southern. The Southern shunters (and the later BR Class 08) had 4' 6" wheels to avoid this problem.

[PaulRhB]

You can't ease tunnel Jn curve because of the approaches to Laverstock loop and it would mean closing the main London Road into Salisbury too to add to the chaos

As only the NMT and specials run occasionally, everything else fits there's no incentive to spend money acquiring land to re profile the loop approach and London Rd bridges.

There aren't any restrictions on 158/9's and the mk3 one was only on short swing links so I assume it's the way that affect the overhang somewhere.

[John M Upton]

Restrictions in my part of the world seem to have included no Class 47's or similar south of Horsham on the Arun Valley (since rescinded I believe although there is a loco hauled speed restriction over a viaduct north of Amberley) and as already mentioned the Arundel Junction to Littlehampton Junction side of the 'Arundel Triangle' is restricted for 23m stock although the other side is apparently fine so a FGW 158 could in theory divert into there in an emergency.  There was a tentative plan to run a 442 service Littlehampton to London in the peak once but that was quickly binned when Network Rail pointed out this problem.

[Gwiwer]

 

There was a tentative plan to run a 442 service Littlehampton to London in the peak once but that was quickly binned when Network Rail pointed out this problem.

 

 

Eastbourne gets one but the west coast doesn't.  That hasn't gone un-noticed by the commuting populations of West Sussex towns.  The curve into Littlehampton prevents such a service taking that route but nothing prevents it starting and finishing at West Worthing, Barnham, or Bognor.  I know of a few regulars who have chosen to change at Brighton in order to enjoy the 442s rather than risk being landed with a 3+2 seated coach on a 377 all the way up or back.

[Oldddudders]

Restrictions in my part of the world seem to have included no Class 47's or similar south of Horsham on the Arun Valley (since rescinded I believe although there is a loco hauled speed restriction over a viaduct north of Amberley) and as already mentioned the Arundel Junction to Littlehampton Junction side of the 'Arundel Triangle' is restricted for 23m stock although the other side is apparently fine so a FGW 158 could in theory divert into there in an emergency.  There was a tentative plan to run a 442 service Littlehampton to London in the peak once but that was quickly binned when Network Rail pointed out this problem.

Is that Timperley Viaduct?

 

Where service density is not an issue, the kinematic envelope problems may be addressed within the signalling system - by ensuring the opposing road is blocked while the 23m stock passes over the affected section. After all, when Chelsea Bridge was found to be a bit marginal on strength in the early '80s, opposing flows were prevented by the signalling system, ensuring only one train at a time on the bridge. I think in SR days, Lewes Tunnel needed a Special Instruction for certain stock after it was found to be a bit OOG.

[Gwiwer]

Timberley I know it as but what's in a name?  Timperley is near Manchester

 

It's always been a little tight to gauge from memory and being wood has also had other issues including the occasional fire in the decking.  SR EMU stock isn't a problem and most locomotive types were not normally used on that route.  But I too recall a restriction on the larger types such as class 47 though they do run that way now at times.

 

Lewes Tunnel had a restriction IIRC due to the curve right off the platform ends at that station which prevented easing of the gauge until platform 1 (the former Eridge bay / down loop platform dating from the days of the Hamsey Loop) was decommissioned; again EMU stock was not a problem but anything slightly larger was.  Traffic density there has seldom been an issue with mostly just an hourly service and I believe the alignment has now been altered to lift that restriction as the old platform 1 is long gone.

[John M Upton]

There are two, Timberley is the big one, horrible thing, always wobbly going over it (looks a bit like a miniature version of The Cassandra Crossing for those who know the film!!) the slightly smaller one Thorndell.  Both go over the River Arun.

 

I would have put the names of them on my first post but my mind went blank, and I am an instructor who is supposed to know these things....