WTT 70 & Hainault to Woodford Shuttle

Exactly! I do wonder who made the decision to allocate a de-icing train to a four-car. Someone, somewhere must have asked for it to be provided, and someone, somewhere, knew it wouldn't be possible - unless there is reformation and conversion of a couple of two-car units, which I guess would be rather costly. As aslefshrugged says, we will have to wait and see - as and when. (Seems to me to be a bit of the right and left hands not knowing what's going on in either?).

Not knowing the specifics of the 1992 stock is it possible to swap the deicing car from a B-D unit with the B car in the A-B units with some wiring modifications?

B-D cars, not B-C (although C and D cars are pretty much identical bar sleet equipment).

Central line trains can be formed in pretty much any combination but A-B+B-C+D-B+B-A would be a typical de-icing set up on an 8-car.

The equipment is indeed turned on/off from any A end cab.

The D car will have de-icing equipment (to spray fluid) and I believe the cab ends all have sleet brushes to physically clean the rail head.

only briefing We’ve had is the new J door opening system 🙄

1992 Stock de-icing D cars are 934xx .

924xx B cars don’t carry de-icing equipment.

I.ve been following this thread for some time and I feel more confused than ever. Let me see if I have this straight. I get that there are A, B and C cars. The A cars are the ones with cabs, and are semi-permanently coupled to a B car. The C cars have shunt controls.

So, for an eight car train you have an A-B pair at each end. In the middle you normally have 2 B-C units with the C ends coupled together at the centre of the train. But theoretically you could have any combination of A-B and A-C units facing either direction. On some trains the C car is replaced by a D car fitted with a deicer unit. This would normally be the 4th or 5th car, depending on the direction of travel, although theoretically it could be the 3rd or 6th. It would be controlled by the leading A car.

If this is all true, then it is simple even for me to understand why you cannot have a 4 car deicer train as things stand.

B-C, not A-C, but otherwise that is my understanding.

Each 2-car unit has one B car and one other car (A, C or D). A 4-car train has to have two A-B units, if it is to have a driving cab at each end!

And to tie up, yes, you can couple any combination of units together in any order, the only real life constraint being that A cars must be on the outer ends.

If I get some time later I’ll try and put together all the possibilities.

For an eight car train, the possibilities are

AB-BC-CB-BA
AB-BC-BC-BA
AB-CB-BC-AB

AB-DB-CB-BA
AB-BC-DB-BA
AB-DB-BC-BA
AB-BD-BC-BA

AB-BA-CB-BA
AB-BA-BC-BA
AB-AB-CB-BA
AB-AB-BC-BA

AB-BA-BD-BA
AB-BA-DB-BA
AB-AB-DB-BA
AB-AB-BD-BA

AB-DB-BD-BA X
AB-DB-DB-BA X
AB-DB-BD-BA X

AB-BA-AB-BA X
AB-BA-BA-BA X
AB-AB-BA-BA X



Some formations (marked X above) are possible but unlikely in practice. (Two de-icing units (B-D) in the same train, or four cabbed (A) cars). I have not included reversed formations - e.g AB-BC-BC-AB is the same as AB-CB-CB-BA

In which case, surely having the shuttles is pointless and you may as well keep projecting what trains were being projected from Woodford via Hainault to Central London previously through to Central London? I thought the idea of having a 4 car unit was that it would release another 4 car unit for mods, which will obviously not be possible if you then have to stick with an 8 car?

As an aside from 4car, on formations generally, the Wood Lane control system has daily logs of every 92TS train consist running on the railway, literally, back to Day One, archived daily to this day, making a complete record of every formation that's ever run since ATO commissioned, it logs one car number as three digits for each unit, but does record all 4 units, not just the lead cars.

The data is massive. I did once look at trying to pick it out from numerous other fields in the daily files, and attempt to produce a formation record, but there is just too much data, and the burn the haystack to look for the needle approach didn't work to well as in effect it's a stack of needles inside a stack of haystacks.

Someone retired and plenty of time on their hands might be able to do it, if they could get hold of the files, but there would be over 7000 files by now, increasing by 1 every day.

We do actually use those records. Am no longer at Wood Lane, but when I was, for three different failure investigations over the years we needed historical trend data. I sifted through the then most recent 10-12 years data for specific faults. But what I was looking for was much simpler to find in each case; the trains formations was several orders of magnitude harderer.

True.

But I'd be pretty sure if I suggested for example you could run Cockfosters -> Heathrow loop -> Cockfosters with 73TS formed DM-M-UNDM-DM-M-UNDM I'd be blown out of the water.

That would require a new timetable and duty rosters which would mean carrying on with WTT69 for several months while further delaying the heavy overhaul (should have been completed by August 2017).