Turning units

Ask a silly question, but what need did they have turning trips to turn units ?

Both lines have 'balloon' loops - Northern at Kennington and Central via Hainault. Normal traffic should - if randomly - work them round each loop surely at least once a week if not far far more often, probably daily, forever, while even if one did need turning just ensure it is on a duty that does a loop somewhere.

Sure a Central set may be out Ruislip <> Hainault all day and never go round the loop, but unlikely to stick to such a duty day after day after day. Ditto for Moredens on the Northern. If they did stick, all needs doing is ensure they to a normal duty that loops them when needed ............ but .................

...........But .......... my real question, what is the point of turning it into one particular orientation anyway ? Once in normal traffic, Kennington and Hainault will only turn the set again and again and again forever.

I am not saying they did not have special turning trips - I have no knowledge on this subject - and I can understand a possible need to turn units - I just don't understand why need to do it with special trips at all on those lines. If someone said this about Piccaddilly (pre Heathrow loop) or Bakerloo I could understand it, they'd need working off their lines for it, which really is a special trip.

Which is the situation on the Picc.

Which was almost a daily occurrence.Used to be 7 WWR and 8 RWR AM stablers at Hainault,sometimes due to service disruptions could end up with more WWR than booked so eight cars sometimes got turned.If we had to send a train in service WWR the line controller had to be told it’s running number in case a push out was required.

As I recall, A-D was a normal pushout. But the D end carried a large spring behind the coupler head, so an A-A emergency coupling could only be split in the depot with some difficulty. And a D-D emergency coupling would only work with a heavy, bulky cast iron emergency coupler adaptor which was carried on each train. It fooled each train that it was coupling with an A end.

I am still lost.

I know the bit about A and D ends and all the rest. But, as I said, that applies to forming the unit up.

0nce the complete unit is formed, what need then is there to turn it ?

If you have a line like Northern, the things turn day in day out if not by the hour, so a unit in specific north to south orientation has no meaning.

On the Central, if there are zero through workings Hainault < > Woodford then all stay the same orientation; so the only need then is out of course working when does traverse the loop one way. Is that all ?

But even then I don't fully get this. If the entire 1962 fleet is correctly formed they were symmetric, each 4car half unit a mirror image of the other. Why did it then matter which way round each complete 8car unit is with respect to each other or the east west geography ?

I do not see how a reversed 1962 8car correctly formed within unit - just back to front - is not a 'good train'.

Nor how you can have any non 'good' trains on the Northern; every time one traverses Kennington it reverses orientation so on that argument alternates 'good' 'not good'.

There must be some detail subtlety here not yet explained.

Basically they really didn’t want WWR trains in service on the Central because of the emergency coupling issues so we had the turning moves to balance the right and wrong way trains,if we had too many right way trains we’d turn them as otherwise they would be WWR after entering service via Grange Hill.On the Northern it was only units that got turned as so many trains were turned in service during the day it wasn’t worth it.

Weren’t the de-icers still double ended as the Chesham shuttle was still in operation then?

Perhaps the Central line convention, of all facing west on the main, dates back to Standard stock days and opening of the eastern extensions. There were far more failures back in those days with major delays to passengers. So correctly facing trains arrive at Hainault depot at both ends to stable, but those via Woodford now face the opposite direction to those via Newbury Park. To avoid trains turning on the loop back to town, they must return to service back the way they arrived. But if service variations meant that more than scheduled arrived that night, there will be insufficient trains to meet the morning schedule formed correct direction. Say the last few stablers arrived via Newbury Park due to a points failure at the Roding Valley junction preventing stabling via Woodford. The failure is fixed by morning, but the depot is hard pressed to provide correct facing trains. I guess they would be diverted in the morning to enter service the direction they arrived, with service implications. But if it had happened earlier, then turning trips could have been arranged to ensure the morning start up went to schedule.

Talking about stock imbalances after one of the Leyton collisions Hainault ended up +12 on the stock balance,there were trains stabled on south shunting necks,between sheds.With the controller pinching stablers to make up the stock shortage at the west end of the line there was only 3 stablers out of 15 at Hainault the next day.

OK, let's have a bash at this.....

Before we start, I am not 95 stock trained, but for the sake of keeping things simple I'm assuming a Northern line 95 stock train is made up of two 3 car units. Nominally these will be made up of xx number of "North facing" units and an equal number of "south facing" units. These units will be numbered in a particular manner - for example all the even numbered units are "North facing" and all the "South facing" units are odd numbers (again I don't know which way round it's done on the Northern line but humour me).

Crucially, you cannot couple two even numbered "North facing" units together; nor can you couple two odd numbered "South facing" units together.

Now obviously trains will naturally turn around in service, but they will always be made up of one even numbered unit and one odd numbered unit.

Now lets say for example you've got two defective trains in the same depot, one "North facing" and one "South facing" (so the unit numbers on the first train are even-odd and on the other train they're odd-even). The defect on the "North facing train is on car one (even end) and the defect on the "South facing" train is on car six (even end).........that means both good units are odd numbered "South" units which can't be coupled together. Had both trains been facing the same way, the good units would be an odd and an even which can be coupled together to make a "good" train.

Hope that makes some sort of sense.....

Ah!

Well that's my explanation disproved then. I'll leave it posted though as the theory behind it may well have applied at some time or other somewhere on LU.

for the effort though; your way of thinking is the same as mine in one part - but not in another with others.

I agree, in general, (re)forming up trains in depots with your north facing and south facing analogy if that is what needed to be done. Never mind A ends D ends or such stuff, north and south explains it just as well.

Where I am not understanding - and what others are saying - is that I see that bit as applies only to forming a unit correctly in a depot. Once the thing is in traffic, there can not be a need to turn a Northern line unit into a certain n-s orientation as it is going to invert s-n n-s s-n etc every time it goes via Kennington loop.

Unless someone is going to now say there are certain units that must not route via Kennington loop. Which I am 99.9999% sure will be new info to all if there are such units.

Yes. Irrelvant to 95TS

I have been assuming people who introduced Northern into this discussion were referring historically to before 95TS just in the same way Central discussion is about before 92TS.

There was no booked stock for particular trains in the WTT,any stock could run on any train except in the winter as only 59TS had de-icing trailers so they were on booked de-icing trains.Still had the problems of RWR & WWR units,the most frustrating thing was if you had a good 7 car in the depot but one unit was59TS & one was 72TS.