Route Availability/Weight Restriction Categories for the Big Four?

[JimC]

It struck me that all of the big 4 must have had route availability categories based primarily on axle loading, and it might not be a bad thing to have them all listed together. I have the GWR ones, which are fairly readily available, but I've struck out for the rest of the Big Four. All I've readily found is a modern Network Rail list, and that on Wikipedia where one may never quite be sure. That list, combined with the GW list FWIW is this:-
 

Route Availability   Axle Load Tonnes  Tons/Cwt
GW uncoloured                           14T
GW Yellow                               16T
NR RA3               ≤16.5 tonnes       16T  5cwt
GW Blue                                 17T 12cwt
NR RA5               ≤19.0 tonnes       18T 14cwt
GW Red                                  19T 12cwt  **
NR RA6               ≤20.3 tonnes       20T
NR RA8               ≤22.8 tonnes       22T  9cwt
GWR double Red                          22T 10cwt
NR RA9               ≤24.1 tonnes       23T 14cwt
RA10                 ≤25.4 tonnes       25T

** Usually given as > 17.12 and not a King. 
19:12 was the usual maximum on red route locomotives, 
but some Hawksworth locos were 19:14 and the Bear, 
which was not permitted on all red routes, was 20T,

 

Does anyone have available steam era RA lists? Especially the big Four?

 

Jim C 

Edited September 1, 2021 by JimC

[The Stationmaster]

The LNER seems to have used a numerical based Route Availabiliy system (as I believe the LMS might also have done).  The LNER system - continued on the Eastern Region and presumably the NE Region ran from RA1 (lightest) to RA9 (heaviest but I can;t find the permitted axleweight tonnages and unfortunately it doesn't get a mention in OS Nock's late 1940s paperback about LNER loco classes.

[Steamport Southport]

To my knowledge the LMS didn't have an official system. Can't recall seeing one mentioned in any books.

 

Then the LNER RA system was adopted during BR days  (maybe a bit earlier (during the war?)). Quite possible due to the blurring of the Regions in places like Yorkshire and the Cheshire Lines.

 

I think they had more problems with the different loading gauges and what side drive they were than axle weight. So locomotives tended to stay on duties and in the areas they were built for. The pre grouping locomotives tended to stay in their pre 1923 area. 

 

As an example this Claughton has had a modified loading gauge for working onto other lines. I believe that was pretty rare for such a loco.

 

https://www.warwickshirerailways.com/lms/lnwrrm4000.htm

 

 

 

Jason

[LMS2968]

3 minutes ago, Steamport Southport said:

To my knowledge the LMS didn't have an official system. Can't recall seeing one mentioned in any books.

 

Then the LNER RA system was adopted during BR days  (maybe a bit earlier (during the war?)). Quite possible due to the blurring of the Regions in places like Yorkshire and the Cheshire Lines.

 

I think they had more problems with the different loading gauges and what side drive they were than axle weight. So locomotives tended to stay on duties and in the areas they were built for. The pre grouping locomotives tended to stay in their pre 1923 area. 

 

As an example this Claughton has had a modified loading gauge for working onto other lines. I believe that was pretty rare for such a loco.

 

https://www.warwickshirerailways.com/lms/lnwrrm4000.htm

 

 

 

Jason

Not just the Claughtons. Most LNWR engines transferred to the Midland division had the modifications, notably to the cab roof edges, where the large gutters were cut off and curved, small ones fitted extending partway up the roof (as in the photo), and the roof itself lowered. The most notable class was the Super D, all of which were so modified, even those retained on the Western Division.

 

I think the LMS simply listed banned (or allowed) classes in the Sectional Appendix; there was no indication of restrictions on the engine.

[D9020 Nimbus]

The BR system was derived from the LNER system — BR's first Chief (Civil) Engineer, JCL Train (!) later Sir Landale Train, was ex-LNER. Pretty sure there was an RA 0 as well …weren’t J15s RA 0?

Edited September 1, 2021 by D9020 Nimbus
Typos

[MarkC]

Some anomalies came up too. As an example, the LNER banned certain classes from the Scarborough & Whitby, and also the line from Whitby to Saltburn via Staithes, not because of axle loadings but wheelbase, following some derailments.

[Wickham Green too]

Never heard of a weight-based restriction system on the Southern ..... loading gauge certainly : -

 

Former Pullman Kitchen First “Formosa/Maid of Kent2” built 1921. : Kings Lynn, 26/6/81 

[jim.snowdon]

9 hours ago, The Stationmaster said:

The LNER seems to have used a numerical based Route Availabiliy system (as I believe the LMS might also have done).  The LNER system - continued on the Eastern Region and presumably the NE Region ran from RA1 (lightest) to RA9 (heaviest but I can;t find the permitted axleweight tonnages and unfortunately it doesn't get a mention in OS Nock's late 1940s paperback about LNER loco classes.

Whilst the RA indices generally follow the axleloading, there can be anomalies due to differences in the weight distribution - in simple terms, the weight per foot run, determined by both the variations in axle loading between axles and the wheelbase. I am sure I can recall reading a post, probably from the SM himself, that there were instances of GW/WR locos being allowed over specific routes that had a lower classification.

 

One thing that has changed with modernisation has been the use in large numbers of maximum weight, ie 100T, bogie wagons. With two wagons coupled together, that creates a 100T loading over quite a short distance, which in turn creates a more concentrated load on bridges. What effect this has had on the Civil Engineers is an interesting question.

 

[JimC]

Thanks folks. So it looks as if the LNER system has continued to the present day - maybe with a bit of rounding, and the LMS and Souhern didn't have formal categories, instead having the information against classes in the sectional appendix or similar document. I have the equivalent GW document and it does go into a lot more detail about what is allowed where than basic RA would tell you, so presumably the other lines never found a need for the more formal classification. 
Its interesting that the GWR red route classification (which with the exception of the Kings and the Great Bear was the heaviest) is relatively light, coming just under RA 6 in LNER terms. The GW and LNER systems don't seem to be directly comparable though as Jim Snowdon suggests above. For example I note that in my late 50s Observers book the 04/ROD is listed at RA6 in the LNER scheme, but the GWR have theirs at Blue, which is nearer RA4 than RA5. Roughly the same weight is quoted for both in the book, so it doesn't seem to be a case of the specific gravity of Swindon steel.
I must try and get a sight of an LMS and SR Sectional appendix and get a feel for how they are laid out. Has anyone got either (or their early BR regional equivalents) they could let me have a photo of the relevant pages?

[Nearholmer]

22 minutes ago, JimC said:

I must try and get a sight of an LMS and SR Sectional appendix and get a feel for how they are laid out. Has anyone got either (or their early BR regional equivalents) they could let me have a photo of the relevant pages?

 

I have a 1935 SR Sectional for the Central & Eastern, and it says nothing at all about this subject, or the allied one of gauge clearance, so I think they must have been covered in the General Appendix, the WTT itself, or some periodically issued notices.

[JimC]

8 hours ago, Nearholmer said:

 

I have a 1935 SR Sectional for the Central & Eastern, and it says nothing at all about this subject, or the allied one of gauge clearance, so I think they must have been covered in the General Appendix, the WTT itself, or some periodically issued notices.

Thanks. I've since discovered that on the Western Region the detail was covered in Service Timetables, so most likely equivalent documents elsewhere.

[LMS2968]

I knew I'd seen it written down somewhere!

[TheSignalEngineer]

That LMR table format is the same as the way information is shown in the current Network Rail Sectional Appendix.

 

The GWR had a route availability map. There is a copy of one on the Michael Clemens Railways website,  sorry no link at moment as I am typing on phone. They also had the local prohibitions listed in the Working Timetable, such as Kings and 47xx not allowed through crossover between platforms at station 'z'.

[Wickham Green too]

I have something similar to the L.M.R. for the Southern ( somewhere ) - as above it's listed on a class by class / line by line basis rather than axle or overall weight classification.

Edited September 2, 2021 by Wickham Green too

[TheSignalEngineer]

26 minutes ago, TheSignalEngineer said:

The GWR had a route availability map. There is a copy of one on the Michael Clemens Railways website,  sorry no link at moment as I am typing on phone.

This is the GWR map for route colours. Engine types are noted on the map.

http://www.michaelclemensrailways.co.uk/?atk=634

[The Stationmaster]

18 hours ago, D9020 Nimbus said:

The BR system was derived from the LNER system — BR's first Chief (Civil) Engineer, JCL Train (!) later Sir Landale Train, was ex-LNER. Pretty sure there was an RA 0 as well …weren’t J15s RA 0?

My old ABCs show the J15 as RA1 - but that is obviously a secondary source.

[The Stationmaster]

11 hours ago, jim.snowdon said:

Whilst the RA indices generally follow the axleloading, there can be anomalies due to differences in the weight distribution - in simple terms, the weight per foot run, determined by both the variations in axle loading between axles and the wheelbase. I am sure I can recall reading a post, probably from the SM himself, that there were instances of GW/WR locos being allowed over specific routes that had a lower classification.

 

One thing that has changed with modernisation has been the use in large numbers of maximum weight, ie 100T, bogie wagons. With two wagons coupled together, that creates a 100T loading over quite a short distance, which in turn creates a more concentrated load on bridges. What effect this has had on the Civil Engineers is an interesting question.

 

Yes Jim - what mattered as well as individual axle weights was something called the 'Bridge Curve' which i presume dealt with the distribution of weight and total weight rather than just individual axle loadings - and civil engineers around to tell us more?

 

2 hours ago, JimC said:

Thanks. I've since discovered that on the Western Region the detail was covered in Service Timetables, so most likely equivalent documents elsewhere.

I can't find anything in either teh SR or LMS sectional Appendixes issued in the 1930s (and the same goes for the GWR of course) - apart from local references to 'engines must not pass beyond' etc

 

From the early 1960s the Wr transferred Route availability information from the WTT to a special Route Availability booklet - same sort of idea as the LMR one illustrated above - and I know that that the SR and ER also issued RA booklets.  So perhaps an edict was issued from on high, presumably as part of WTT content standardisation, to take the information out of the WTT and transfer it to a separate booklet (where it remained throughout BR days)?

 

The full list of GWR RA details was as follows in respect of the colours used on the map  -

 

Hatched red (=Double red on the engine cabside)

Red

Dotted red

Blue

Dotted Blue

Yellow

Uncoloured

 

Basically the 'Dotted' routes were of the lower colour (e.g. Dotted Red was actually a Blue route) which engines in the next higher group were allowed to use subject toa. blanket restriction of speed, e.g. Red engines were limited to a maximum speed of 25mph on a Dotted Red route (plus possible other restrictions including a lower blanket restriction).  In certain instances specific classes of engines in the next heavier group were allowed to work over some lines without the 'Dotted' system being applied - the best example of ths was 'Manors' (Blue) allowed to work over parts of the former Cambrian system which remained as Yellow coded routes.

 

 

[Nearholmer]

Possibly the best SR restriction was one at Newhaven, where there was a sign saying “No engines must pass this board except the A1 Class Fenchurch”, which is pretty specific!

[pete_mcfarlane]

1 hour ago, Nearholmer said:

Possibly the best SR restriction was one at Newhaven, where there was a sign saying “No engines must pass this board except the A1 Class Fenchurch”, which is pretty specific!

Especially as that loco had lost its name decades previously. 

[JimC]

As is my wont with a topic I haven't found very accessible information for I'm knocking up a web page with what I've discovered. If you're interested its here. https://www.devboats.co.uk/gwdrawings/weightrestrictions.php

 

Edited September 2, 2021 by JimC

[Steamport Southport]

10 hours ago, Nearholmer said:

Possibly the best SR restriction was one at Newhaven, where there was a sign saying “No engines must pass this board except the A1 Class Fenchurch”, which is pretty specific!

 

First of the class in service though, and probably proof they never officially called them Terriers.

 

https://sremg.org.uk/steam/a1-a1x.shtml

 

Using the first named engine as the class name was pretty common.

 

Lord Nelson, Remembrance, King Arthur, Coronation, Silver Jubilee, Patriot, Green Arrow, Sandringham, Claughton, Precedent, Precursor, etc.

 

 

 

Jason

Edited September 2, 2021 by Steamport Southport

[Wickham Green too]

But how many of those class names had any official recognition ? ......... yes, on the Southern, what we know as the 'Lord Nelsons' were 'LN' class - which is pretty close - but the 'Remembrances' were officially 'N15x' class, the 'King Arthurs' were 'N15' class .......... moreover, "Remembrance" and "King Arthur" were not the first of their class in any sense. ( Others will comment on other railways, no doubt.)

 

( There was never a loco called "River", "Schools", "Merchant Navy", "West Country" or "Battle of Britain" ! )

 

[62613]

Was the unbalanced mass (weight) of the running gear taken into account anywhere?

[Nearholmer]

14 hours ago, Steamport Southport said:

First of the class in service though, and probably proof they never officially called them Terriers.

More to do with the fact that Fenchurch actually belonged to Newhaven Harbour Company (although by then in-named), whereas the rest didn’t.

 

The Terrier name is very old. I found it being  used in The Engineer before 1880.

[Wickham Green too]

Looks like there WAS a degree of official recognition for 'Lord Nelson' & 'King Arthur' class names by 1949 at least. I've found the 'Restrictions applicable...' booklet and attach the cover, first page and a 'typical' class : - 

 

OK, the 'W' is hardly typical as it's banned from passenger work !