Headcodes. Been wondering this for ages.

[Harlesden]

What does each character in a heacode tell a "need to know" person about the train. King's Cross example below.

 

[EM2]

The first character denotes the class of train.
The second is the route or destination area.
The third and fourth are the service identifier within the route.

The Wikipedia article is pretty good: http://en.wikipedia.org/wiki/Train_reporting_number

 

[sultanofswing]

2P08

2=Class
P=Destination
08=Sequential Number for the route, so this would be the 8th train on that route

 

[hello]

2P08

2=Class
P=Destination
08=Sequential Number for the route, so this would be the 8th train on that route

interesting, 1s35 0609 bath to glasgow, does that then mean that it is the 35th train through bath in the morning?

 

[swt_passenger]

interesting, 1s35 0609 bath to glasgow, does that then mean that it is the 35th train through bath in the morning?

Not at all.

I think it would be better to explain that sometimes, in some areas, the two digits run consecutively over the course of a day, but it isn't set in stone. Odds and evens may define different directions, but not always. In any case, XC's trains would have their own number sequence relevant to their needs on their main SW routes, different to the other operators at Bath.

The letters don't have unique meanings either, it depends on the area.

 

[dave_wm]

I would describe the last two numbers as simply an identifying number:

1S35 follows 1S31 (0600 Birmingham New Street to Glasgow Central) and 1S33 (0703 Birmingham New Street to Edinburgh) beyond Birmingham - they'll be numbered 1S3x to avoid confusion with other services; 1S05, for example, is the 0700 London Kings Cross to Edinburgh.

Some seem more random; the 0710 Derby to Nottingham is coded 1B99 for example.

 

[Tomnick]

In some cases, trains are numbered 'out of sequence' to highlight, for example, an unusual stopping pattern or a slightly different routing. They don't always start at zero either - our hourly passenger trains are numbered starting at 1L26 in one direction and 1N40 in the other (but generally increasing in twos after that). Sometimes it just makes no sense at all .

 

[Eagle]

Although of course trains that are separated (in time or in space) have no problem with repeating headcodes. For instance 1S35 refers to three trains:

0618 Manchester Airport to Glasgow Central
0609 Bath Spa to Glasgow Central (several hours after the first, so no confusion)
1345 Faversham to Dover Priory (other end of the country)

 

[swt_passenger]

I'd also mention that codes are generally only unique as far as is necessary to avoid confusion in a single area, a query of RTT shows there are three trains that use the short code 1S35:

0609 Bath Spa to Glasgow Central
0618 Manchester Airport to Glasgow Central
1222 London Victoria to Dover Priory

If they ever meet up at a junction together there'd have been major problems somewhere; nevertheless it is slightly odd that there are two arrivals at Glasgow with the same code...

Snap. Same thoughts as Eagle.

 

[Eagle]

nevertheless it is slightly odd that there are two arrivals at Glasgow with the same code...

One arrives at 09.45 and one arrives at 14.12, which is probably enough to limit confusion (unless the TPE train gets delayed for four hours somehow).

There are a few instances where the same headcode refers to the same service at two different times of day, mainly on high-frequency routes where there are more than 50 or 100 services a day. The Stourbridge Town shuttle is an extreme example of this: it starts in the morning with 2P01 and runs through the entire list of numbers twice before ending with the third 2P14 of the day.

 

[dave_wm]

I have heard there was some degree of confusion a few years back when Chester - Birmingham services were numbered in the same 1Gxx series as London - Birmingham expresses, and occasionally two identically headcoded trains arrived at Birmingham New Street from different directions at the same time...

 

[The Planner]

True, irate signallers ensued....

 

[83G/84D]

In the Westcountry "Up" trains from the area to London are generally 1Axx.

For the benefit of panel box areas with train describers trains such as 1A16 & 1A35 indicate they route via Bristol Temple Meads whilst trains with higher numbers at the end such as 1A77, 1A83, 1A95 etc are via the "Berks & Hants" route (via Castle Cary & Newbury).

Down trains are mostly 1Cxx from London to Devon & Cornwall.

Local trains vary quite a lot but 2Pxx is normally Plymouth bound, 2Nxx Newquay bound or return, 2Gxx Gunnislake bound or return, 2Fxx Falmouth and 2Axx St Ives. The 2 of course indicates a local stopping train rather than 1 which is an express.

Devon destinations are 2Bxx, 2Exx, 2Fxx, 2Rxx & 2Txx.

Only so many variations are possible so codes are reused around the Country but generally not in areas close together.

Cross country are 1Exx, 1Mxx, 1Oxx, 1Sxx, 1Vxx according to the old regions destination / origin. A train from Plymouth to Scotland would be 1Sxx for example.

It is quite complex and there are variations from the norm but this is just a brief insight.

Trains beginning with 4 are mostly Freightliner, 5 are generally empty stocks and 6-8 freight trains with various maximum speeds.

Class 0 indicates light engine(s), whilst Class 3 is used quite a lot for test trains and the like.

 

[Eagle]

Only so many variations are possible so codes are reused around the Country but generally not in areas close together.

Two classes, 24 letters (X and Z are reserved for emergency and altered trains respectively) and 100 numbers makes a total of 4,800 passenger codes. Whereas the number of passenger services per day in the country is around 22,000.

 

[TheEdge]

Out here in the East we have;

1Pxx for the GEML expresses
2Sxx for Bittern Line
2Pxx for Norwich to Yarmouth via Acle
2Cxx for Yarmouth via Reedham
2Jxx for service to Lowestoft
2Dxx for East Suffolk
2Rxx for Felixstowe
1Kxx (2Kxx for stoppers) for Norwich - Cambridge
2Wxx for Ipswich - Cambridge
1Lxx (I think) for Ipswich - Peterborough

Out of interest are class 7 and 8 trains seen that often anymore?

 

[83G/84D]

A fair few Class 7 trains around but not many 8's that I know about, maybe the odd move of a Class 08 with a few wagons (such as "cripples") on the mainline perhaps?

 

[33056]

...... (X and Z are reserved for emergency and altered trains respectively) ......

X is used for an exceptional load or something with a routeing restriction.

On the subject of trains with the same headcode I recently saw two trains with the same headcode departing somewhere at the same time but in opposite directions hock:

 

[30907]

There are a few instances where the same headcode refers to the same service at two different times of day, mainly on high-frequency routes where there are more than 50 or 100 services a day. The Stourbridge Town shuttle is an extreme example of this: it starts in the morning with 2P01 and runs through the entire list of numbers twice before ending with the third 2P14 of the day.

Worth adding that in the earlier years of the system branch line class 2 trains (certainly on WR) carried the same code all day (depending on the branch, but IIRC always 2B9x), a headcode (route code) in the SR sense. Not sure when this was changed, but presumably the idea was not clever in a power box area.

 

[Manchester77]

Class 9 is used for London Overground and was used iirc for Eurostars when they used to run into Waterloo?

 

[Eagle]

Class 9 is used for London Overground and was used iirc for Eurostars when they used to run into Waterloo?

Eurostars are still coded as Class 9, which is so that they can keep the same train number that they use on the continent (with the cheeky substitution of 90xx and 91xx to 9Oxx and 9Ixx).

LO use Class 9 on the ELL, which was a consequence of running alongside so many other services in the southern region that there were not enough free Class 2 letters to use. (All other LO services use Class 2 as normal.)

And also, from December, London to Scotland via Birmingham services will take Class 9 numbers to prevent clashes with the existing London to Glasgow services (being as both will use the letters M and S). VT did a similar thing with XC services for a while in the mid-2000s.

 

[Darren R]

In the North West, along with the letter the two digits are used to signify the route (we just love to be different! ) . Trains terminating at Manchester Victoria mostly are 2Jxx, and those terminating in the wider Preston area carrying the letter N. The two digits are allocated a specific series according to route. Hence Ormskirk to Preston services are alloted the odd numbers in the range of 2N01 - 09; Blackpool South to Colne even numbers 2N10 - 18; Manchester to Blackburn/Clitheroe even numbers in the range 2N50 - 60, and in the opposite direction 2J50 - 60 (because they're going to Manchester Victoria.) Etc etc...

I often marvel that wrong routes aren't set on a daily basis!

 

[MCR247]

LO use Class 9 on the ELL, which was a consequence of running alongside so many other services in the southern region that there were not enough free Class 2 letters to use. (All other LO services use Class 2 as normal.)

I always thought it was to avoid confusion at New Cross Gate to avoid signallers accidentally setting a route for an LO to LBG etc)

 

[Manchester77]

Thanks for clarifying Eagle, out of interest are HS1 SouthEastern services given different head codes to make sure they get sent down HS1 rather than the line to Charring X?

 

[ValleyLines142]

Thanks for clarifying Eagle, out of interest are HS1 SouthEastern services given different head codes to make sure they get sent down HS1 rather than the line to Charring X?

No, HS1 services have a 1Jxx headcode.

 

[EM2]

X is used for an exceptional load or something with a routeing restriction.

On the subject of trains with the same headcode I recently saw two trains with the same headcode departing somewhere at the same time but in opposite directions hock:

It happens quite often at St Pancras for services departing quite close together, for example, 1F10 is the 07:25 SE HS service to Faversham and also the 07:55 EMT service to Sheffield. Off the top of my head, I can't think of any departing at the same time.

 

[LNW-GW Joint]

I can't understand why the old Regional destination letters are still used, 20 years after the Regions were abolished!
These are M (London Midland), V (Western), S (Scottish), E (Eastern), O (Southern), and even N (North Eastern) for a while until it was folded into Eastern.
The Regions then internally repeated the letters individually, causing national duplication (eg they all used A for London), so multiple trains have say "1A05".

After all this time, shouldn't it be localised more logically with a unique letter for each destination area?
This would mean (say) Edinburgh and Glasgow, and all the London terminals, having separate letters.
If B means Bristol, why do some trains (which happen to be from Scotland, Manchester or Newcastle) use V?
With a single NR network, it just seems illogical to me.
I know there are now variations on the original scheme (R for instance), but the old Regional structure is still there, even though the Routes have changed.

 

[Eagle]

(By the way, you forgot L for Anglia.)

The regions aren't abolished, Network Rail still use them, albeit in a somewhat altered format (e.g. there is a new Wales region, and the East Midlands have moved to the LNE region).

Also the working timetable is also still divided up according to the regions in their original state, although the letters are different: C for London Midland, G for Scotland, L for Anglia, P for Western, W for Southern and Y for Eastern/LNE. You might be able to spot the pattern for why those letters are used.

So in short, the regions aren't obsolete at all.

 

[87015]

I always thought it was to avoid confusion at New Cross Gate to avoid signallers accidentally setting a route for an LO to LBG etc)

Anyone can use Class 9s should they so choose, nothing special about them any more

http://www.realtimetrains.co.uk/train/F44590/2014/01/04/advanced

 

[Eagle]

Does using a 9 in that case signify some kind of priority? (Like how around London Class 3 is also used to mean priority ECS moves.)

 

[The Planner]

Also the working timetable is also still divided up according to the regions in their original state, although the letters are different: C for London Midland, G for Scotland, L for Anglia, P for Western, W for Southern and Y for Eastern/LNE. You might be able to spot the pattern for why those letters are used.

So in short, the regions aren't obsolete at all.

Even that is becoming a bit of a legacy as the planning regions don't match those.