Met. Description Codes

[mrfs42]

Reading a WTT from '58, Met. No 2 Section TT 170 .Am slightly puzzled by the train descriptions, anyone care to help with explaining them?

Those that seem straightforward are HZZ (Outer R to H'smith), CZZ (OR C'cle), ZZC (IR C'cle), ZZD (IR H'smith - W'chapel).

So far so good - xZZ is Westbound, ZZx covers Eastbound; this holds true for Goods trains, ZZG being used for Acton - Smithfield paths. Others that seems to make sense for terminals are: ZZA - Aldgates, ZZE - Liv StrEet, ZZB - Barking or Plaistow, East Ham Dt, KZZ Wembley ParK, ZZI Moorgate SidIngs, ZZF Farringdon Sidings.

Inner Rail TD codes are much, much, more puzzling - BBA for Aldgate - Ux, but BBE for Aldgate - W'ford. There are also a whole series of MZx codes for Steam stock. MZB for UxBridge, but MCM and MZM for Baker St - Aylesbury.

Are there answers out there? ;D



.

[tubeprune]

Bump Bump I noticed this thread didn't have a reply so I asked a friend who is into this sort of thing and he responded thus:

"The timetables do not contain any lists of codes (until the post 1960 series). A quick check suggests that published codes are of no great antiquity and came into use only after the Second World War, so the ones referred to only had a short life. This will need more research, but an obvious starting point is to look into the train description technology used on the Met, which I think was all relay-based. Therein, I suspect, lies the answer to what appears to be an apparently over-complex coding system. Checking timetables, though, has suggested that it is consistent, which is at least one small benefit."

I have asked him to dig a little more when he has time.

[mrfs42]

Thank-you. I've got a machine-readable database based on the 1958 WTT codes - and there seems to be apparent internal consistency between them.

Since typing that message back in March I've acquired some more Met No1 and No 2 TTs of that vintage. They're waiting in the electric kitchen back in Wales for a moment between trains for analysis. A quick squint shews that there was a method behind the codes, but as yet I've not come up with anything conclusive - I've even tried correlating the present WF0, AM5 et seq.

[mrfs42]

I've been doing a little digging this afternoon......

Sorted through a large pile of recent acquisitions that a freind got for me on - spec. Turns out it's a large selection of District/Picc and Met TTs from the early 50s to the early 60s.

The descriptions seem to come in with TTs 170, 172 in June '58. (171 is a Widened Lines TT), and then seem to have gone with 181, 182 in Jan '60.

I say 'seem' because there are still gaps in the numbering [1] - City Widened and East London were numbered in the Met. series and I've not got those. The size of the TT book changed from landscape (last known Met. No 2 151/ June '54 - although the TT Notice for Easter '56 is still landscape) to portrait (first known 170, 172).

I wonder if the codes came in when the layout of the WTT book was changed and (a bit of a random stab in the dark) the codes are for punching-up the TD code?

[1] well, gaps in what I can lay my hands on

[mrfs42]

Well, well. I suppose all things come to those who wait. I've finally found out the answer to this question that I posed all those years ago:

These are the codes for the SGE one drum TD transmission.

NB Road and Inner Rail

• BBA (all stations to Baker Street, FRd, WmP) (= aaa), PrRd, NwPk, Hw, all stns WHw to Ux.
  
• BBE aaa, PrRd, NwPk, Hw, NHw, all stns to Wf
  
• BCE aaa, Hw, NHw, all stns to Wf except MPk
  
• BBF aaa, PrRd, NwPk, Hw, NHw, all stns to Rk
  
• BCF aaa, Hw, NHw all stns to Rk
  
• BCM aaa, Hw, MPk, all stns to Ay
  
• BBJ aaa, PrRd, NwPk, Hw, NHw, all stns Rk - Wf
  
• MCA (all stns to BkS, FRd) (= ddd), Hw, all stns WHw to Ux
  
• MCE ddd, Hw, NHw, all stns to Wf
  
• MCM ddd, Hw, MPk, all stns to Ay
  
• MZM ddd, FRd, MPk, all stns to Ay
  
• MZN ddd, FRd, MPk, all stns to Chm
  
• MZB ddd [RL] [1], all stns to Ux
  
• MZE ddd, NHw, all stns to Wf
  
• MCL ddd, Hw, MPk, Rk
  
• LZZ ddd, then local to N
  
• JZZ all stations to Baker Street
  
• CZZ Circle Putney line, South Kensington (via High St.)
  
• HZZ all stns to Hm
  
• AZZ Goods and Special
  
• EZZ Empty
  
• ZZZ Local code for shunting moves

[1] [RL] was Eastcote until 31.1.57

Looking at the time, I shall have a snooze: I'll do the Outer Rail and Southbound later on (plus a key for the abbreviationistas).

[mrfs42]

SB Road and Inner Rail

• CCZ Hw, NwPk, PrRd, FRd, BkS (= xxx)
  
• CCH as above, all stations to Aldersgate
  
• CCA xxx, all stations to Aldgate
  
• CCI xxx, all stations to Moorgate
  
• CCE xxx, all stations to Liverpool Street
  
• CAZ xxx, all stations to Baker Street (local road)
  
• CZZ xxx (Hw, NwPk, PrRd, WmP)
  
• DZZ Hw, WmP
  
• DCA Hw, WmP, FRd, BkS, all stations to Aldgate
  
• DCI Hw, WmP, FRd, BkS, all stations to Moorgate
  
• DCZ WmP, FRd, BkS
  
• ZCZ FRd, BkS
  
• ZCE FRd, BkS, all stations to Liverpool Street
  
• ZCA FRd, BkS, all stations to Aldgate
  
• ZAZ N, DHill, WGrn, Kil,WHm, FRd, BkS
  
• ZBZ WmP and all stations to Elephant (Bakerloo)
  
• ZZB Barking Line [2]
  
• ZZC Circle Line [2]
  
• ZZD Whitechapel [2]
  
• AZZ Goods and Special
  
• EZZ Empty
  
• ZZZ Local Code for Shunting Moves etc.

[2] ZZB, ZZC, ZZD added 2.7.56

Abbreviations
BkS = Baker St, FRd = Finchley Road, WmP = Wembley Park, PrRd = Preston Rd, NwPk = Northwick Park, Hw = Harrow, WHw = West Harrow, NHw = North Harrow, MPk = Moor Park, Ux = Uxbridge, Wf = Watford, Rk = Rickmansworth, N = Neasden, DHill = Dollis Hill, Kil = Kilburn, WHm = West Hampstead, Hm = Hammersmith. RL = Rayners Lane, Chm = Chesham, Ay = Aylesbury

There are a few stopping patterns that are no longer used, and moreover there are still a couple of points of conflict that are different from the published WTTs: most particularly ZZG which was used for Goods - I have also seen ZZA in use on the Inner Rail - perhaps time for a bit more digging around - however, it proves that if you are prepared to wait, most of the answers will eventually arrive!