PiccEX Junction

[Deleted]

I went bashing 'round the Heathrow Loop today and was quite surprised to find that the layout of PiccEx Junction is nothing like what I (or some others) expected!

It seems that the original wye, where the loop split into two tunnels which then connected to the overruns from T123, has been retained. The new eastbound line (which resembles a big concrete box instead of a tunnel) then joins from the left when traveling e/b.

Why exactly was this particular setup chosen? I can see benefits to retaining the loop-to-w/b connection, but nonetheless, why was it done?

As an aside, the Heathrow branch seemed to be hosting a staff meet - there were no less than six I/Ops piloting trains through PiccEx Junction; they were based in a portakabin at Hatton Cross, with two DMTs and several big hats lurking nearby. Going up towards Acton I saw more staff, all over the various stations, including several more big hats quizzing drivers at various points. I can understand why piloting through the junction is needed, but why were so many managers about as well?

[agoodcuppa]

theonekea said:

but why were so many managers about as well?

Quite obviously they were on hand in case anything went wrong. The thought of paid overtime wouldn't have entered their minds.

[Deleted]

agoodcuppa said:

theonekea said:

but why were so many managers about as well?

Quite obviously they were on hand in case anything went wrong. The thought of paid overtime wouldn't have entered their minds.

Luckily (or not, for the bashers!) nothing did go wrong.

Interestingly enough, the T4 Loop now smells like damp concrete dust. It's also oincredibly cold down there too!

[towerman]

So,the Picc has to deal with wrong way round trains again.

[Deleted]

towerman said:

So,the Picc has to deal with wrong way round trains again.

Is is too much of a problem though? The Northern, C-stock Lines, and Met also have the same problem.

[towerman]

Yes,but the A,C and 95TS were built with this in mind,the 73TS was built before the loop was constructed.

[agoodcuppa]

towerman said:

the 73TS was built before the loop was constructed.

However, the possibility must have been in the designer's mind as the single-ended cars have mechanical only coupling. It's only if you get two double enders trying to couple A-A or D-D that there's going to be a problem.

Of course, I could be totally wrong and the reason for mechanical only couplers might have been for a totally different reason, like economy.

[robots]

My train was delayed at Hatton Cross earlier this evening

due to the lack of an I /OP to pilot me round so the bodies

had clearly dispersed .

I 'm surprised no one 's mentioned the

lack of DVA on the Picc today . The management had spent

the last couple of weeks preparing handouts and putting

up countdown posters telling everyone that today was the

launch of DVA . What happened ? Apparently nothing , some

reports said only one train was operational others 3 , another

none . I do know only a fraction of the fleet has had the

necessary adaptation work carried out, so why were staff

primed to expect a brave new world . Answers on a postcard

to Mike Xxxxxxx.

Admin Comment: Please don't post the full name of current employee's (though I do understand your motive).

[tubeprune]

agoodcuppa said:

Of course, I could be totally wrong and the reason for mechanical only couplers might have been for a totally different reason, like economy.

You are right in being totally wrong. When the 73TS was designed, there were no plans for a loop so the single-ended cab end couplers were only ever intended for emergency push-outs.

[agoodcuppa]

tubeprune said:

You are right in being totally wrong.

Nothing out of the ordinary there then.

[Oracle]

When I first wrote about the extension to Terminal 4 for UNDERGROUND NEWS two decades ago, the problem of wrong-way trains was something that I mentioned. At the time we had loops on the Central and of course Kennington, plus as mentioned below the Kings X and Euston Loops. At no time did I hear anything about 1973 Stock being designed with T4 in mind, and this was because the proposals were several years after the Hatton X then Heathrow T123 extensions. I dialogued a lot at the time with the planners at the then GLC department that were responsible for the T4 extension and no concern was ever raised about wrong-way trains. I suppose it was thought of as a "necessary evil"? I asked my colleagues in LURS about what they thought about the prospects with the loop turning trains, and the response was that up until the Hainault Depot tried its best to send trains back the way that they came in, and if necessary they would send a train round to correct it. As regards the Northern, well..."it's been all right up until now!" The only time that I can remember any efforts made to turn trains was when stock was transferred back from the Northern via the Euston Loop. With 1959 and 1938 Stock this required either sending it round the Circle or reversing at High Street Ken and the District. I don't recall any concern being raised about Northen trains to and from Acton Works but I shall be interested to know if there were any. Any stock going to and from the Northern would not be turned ordinarily?

I believe from memory the "official" answer I got to the prospect of 1973 Stock trains being sent wrong-way was that the workings would be attempted to be evened-out so that they more-or-less cancelled each other out. That is, trains would end up the right way round at the end of service. However no-one thought it seems about the one or two last trains to T123 which were required as T4 closed earlier.

If however someone knows more than I do about the design of the 73TS please correct me!


May I just add that whilst I was writing about T4, there were other interesting proposals mooted. These included an extension of the SR from Feltham to Heathrow, with a stop at T4 and then T123, and also a monorail from Feltham! However as you all know the T4 loop was subject to delays, and this required a new small Act of Parliament to allow a deviation railway because the loop had to be altered from its original position. Also the BAA as it then was held open the prospect of a station inisde a box in the terminal building. However as a result of delays the BAA had to offer the second-best option and place the staion in the new Car Park adjacent to the terminal. Then, just as al the effort was paying off the discussions started about T5! This had to be it was said, placed where the then Thames Water Board's Perry Oaks sewage farm was. However T5 was put on hold, although the GLC had to consider what to do about a Piccadilly link to T5 just as they were preparin gfor the T4 loop! Regrettably T5 was years away, and was held up by the planning hearing. However it was galling at the time for me to be writing about the T4 loop and then about how T5 was going to be fitted in to the Picc's scheme as well!

[yellowsignal]

Could someone please explain why wrong way round trains are unwanted?

[Oracle]

I am no expert but basically trains are sometimes "handed", for economical and complexity-saving reasons. Thus one end of a train is meant to be able to couple up to another's rear in an emergency to enable it to be pushed. If you have trains that are all mixed up the theory was that you could then have a situation where a train could not couple up to push it because it was incompatible. Stock had "A" ends and "D" ends, so that A could couple up to D, and D to A as required, but like poles repel, and so A-A and D-D were generally incompatible. Some stock was designed to be able to couple up any way round though, despite the end car designation. This was however complicated on the Piccadilly as 1973 Stock as it then was was delivered as units with single cabs and UNDMs and also with some double-ended units for the Aldwych shuttle. I gathered that when built all units could couple up to each other but I did hear that in Northfields Depot in a trial to see what would happen when two double-cab units were coupled together, something thought unlikely to ever happen as the branch was still open, there was considerable difficulty in uncoupling the units.

Also, 38TS and I suppose 72TS could be coupled up by a special bar to the Class 501 DC trains in an emergency north of Queens Park, but not the other way round. I gather the bar was kept in one of the cabs in the BR trains...logically Down/north cab.

Can someone who knows more than I do elaborate please?

[Deleted]

Most Wedgelock couplers are handed - the electrical and pneumatic connections are arranged in such a way that only the arrangement's counterpart can couple up. As Oracle said, this means that 'A'-end Wedgelocks can only couple to 'D'-end Wedgelocks, and if you try to couple a pair of 'A's, it doesn't work.

However, some rolling stock does have Wedgelocks that are universal - the double-ended D stock, the double-ended A stock (a story in itself!), the C stock and the 1992TS all have universal Wedgelocks that will couple to almost any counterpart coupler, including another universal one.

[tubeprune]

yellowsignal said:

Could someone please explain why wrong way round trains are unwanted?

In summary, because they won't couple. In detail, the electrical connectors are split into two boxes on either side of the coupler. This makes the coupler "handed". They can't put the boxes into one box under or over the coupler like the main line railway do because there isn't room on a tube train with a low floor and the negative rail immediately underneath.

If you turn the train on a loop (e.g. Heathrow, Kennington) or triangle (e.g. Watford, Aldgate), the electrical boxes will not face their partners on the next train. This doesn't matter unless you are in the depot and you take off a unit for maintenance or failure and try to couple to another unit only to find it's the wrong way round. Oops - cancel one train for the pm peak

If you want to make the coupler "universal", as was done for the A Stock originally (until it was stuffed modified for OPO) and for the C Stock, you have to double the electrical contacts in each box - very expensive.

The 72TS was designed with "handed" couplers. A 4-car unit had an "A" coupler at the "A" end and a "D" coupler at the "D" end. A 3-car unit had a coupler at the UNDM end only. This would be "A" or "D" depending on which type of unit it was. If it was necessary to couple a 3-car and a 4-car to make up a service train, the UNDM would always match either one end or the other of the 4-car, so you could make up a train.

D Stock double-enders have "handed" couplers. They are like 73TS. They won't couple wrong way round.

The trend now is not to double the connections but to make it work, e.g. 95TS, which has "handed" couplers but the fleet management seem to be able to manage. That said, they do have a good stock of spare trains. The 09TS will also be handed of course. I could go into this a lot more but you can get a flavour of the problem from www.trainweb.org/tubeprune/coupling.htm.

[towerman]

T4 extension was originally meant to be a double track extension,the COM at the time Charlie Cope,had the brilliant? idea to make it a single line loop thus saving mega bucks.

[Deleted]

towerman said:

T4 extension was originally meant to be a double track extension,the COM at the time Charlie Cope,had the brilliant? idea to make it a single line loop thus saving mega bucks.

The T4 loop doesn't need two tracks, so I think the COM (whats a COM?) made the sensible decision.

[towerman]

Chief Operating Manager.

[robots]

I have a slight issue with not being able to name the buffoon

masquerading as Piccadilly Line General Manager . He is a

public figure , he has appeared numerous times in the media

in his role . I don 't feel he is an ordinary member of staff .

Am I allowed to mention Tim O ' Toole ? I think admin should

rethink this one .

[Colin]

robots said:

I have a slight issue with not being able to name the buffoon

masquerading as Piccadilly Line General Manager . He is a

public figure , he has appeared numerous times in the media

in his role . I don 't feel he is an ordinary member of staff .

Am I allowed to mention Tim O ' Toole ? I think admin should

rethink this one .

Firstly, the forum policy is in THIS THREAD.

All employees have a right to not have their name's etc made public - manager or not. There are other issues related to this such as the Data Protection Act, Human Rights Act, etc etc. How would you feel if you visited this forum for the first time and found out someone had been saying things about you without your knowledge or consent?

BTW, does this person know you had put their name on the internet?

Did you know that you could be disciplined for releasing such information (ie, personal information)?

Like I said in the original edit, I do understand your motive - but as an employee of LUL myself and an admin on here, I cannot condone it.

[Phil]

And to back Colin up, I support his stance entirely. Apart from what's said above, the guy has no right of reply on this forum and that just ain't justice. We all like to name and shame but in this case it isn't fair on the guy however poor a manager he is.

So the policy may be irritating but in our 'sue,sue, sue' age it has to be.

[agoodcuppa]

I have to agree with the admins on this one (creep, snivel).

While there is a time and place for pillorying specific individuals who perform less than well, this isn't it.

Whilst there's nothing to stop a named individual signing up and defending his or her actions the risk then arises of this becoming a place for airing an organisations dirty washing in public, and that's not what this forum is about.

[Oracle]

I was a third party at the time that the T4 extension was developed and as I said I contacted and was sent information from the GLC department including stuff that should never have been released. I agreed to keep it confidential. I wrote about the subject virtually every month for UN for several issues. I have never personally seen anything that suggests that there was to be a double-track extension although I find it interesting that I may have missed it, or have mislaid that aspect in my memory banks.

You have to understand that there was a different regime at the time as LT was under GLC control. I have to say with hindsight, although my writings reflected this at the time as it was pure fact, prevarication about aspects of the link saw the British Airports Authority deadline for the reservation of the station box in T4 itself being exceeded, and there was concern generally that it might not have even been possible to place the station in the Car Park to be built adjacent to the terminal building. I am sure that I recall correctly that the BAA quoted a price for reserving the station box, and because the fundng or whatever agreement could not be reached on the "GLC/LT side", the second-best alternative resulted in greater cost. The MIDDLESEX CHRONICLE local paper had regular updates about this.

I believe that I am right in suggesting that any decision to make the link a loop was attributable to "a higher plane" than even LT management as apart from the GLC running LT, BAA was until 1986 a state-owned statutory authority. The T4 link had to have private Acts of Parliament to authorise its construction.

[Deleted]

towerman said:

Yes,but the A,C and 95TS were built with this in mind,the 73TS was built before the loop was constructed.

Sometimes Neasden still send trains up to Watford and request them turned round the north curve at Rickmansworth. Im sure the Trips to Heathrow and back will start resuming for 73ts?

[Oracle]

The Lymington slammers are routinely sent to Fareham, then Eastleigh, and then back to Bournemouth Depot to turn them, and I was once on an HST that was turned at Dr Days Junction, Bristol...it is still possible in theory for a DMU to become turned via Bristol Parkway and then to Bath or vice versa.

[Chris M]

Partiuarly when there are engineering works it is not uncommon for HSTs to be turned in the Bristol area , apparently the most common method of resorting them to get the first class back at the London end is Bristol TM - Bedminster sidings - St Phillips Marsh Depot - Bristol TM. There are several possible routes in the area, e.g. I was on a HST that ran Bath - Rhubarb Curve - Bristol Parkway - South Wales, but as limited direct working direct from Swindon was happening trains in South Wales were running in both orientations.

[towerman]

The claim about the T4 loop I got from the horse's mouth at a course at Flagstaff House.He said that there were worries that the extension was going to be late and over budget,so he made the suggestion about a single line loop,and it was welcomed with open arms.

[Oracle]

...He said that there were worries that the extension was going to be late and over budget..,

That must be fact in my opinion and borne out my reading of the situation. I have just mentioned about the station box problem and the need then to obtain a new Act of Parliament to allow a slight deviation of the route on a curve, which just added to everything!

As to whom it was that suggested it, well I am interested and keeping that interest open. I would in due course like to pin it down, and the answer will be in the former GLC files I suspect.

[Deleted]

robots said:

I have a slight issue with not being able to name the buffoon masquerading as Piccadilly Line General Manager

I see your point robots and completley agree with you , having had the gentleman in question in my cab a few weeks ago ,what he actually knows about 73 stock i could write on the back of a postage stamp, the man is a twonk .. but this being an open forum , the powers of censureship are quite strong and sometimes border on the ridiculous.

[Oracle]

SPD: when were you first on the Picc? I wondered whether you might have chauffeured me yonks ago? I used to "cab" with my friend who hailed from Arnos Grove, now off LU, when I got on at Hounslow West or on the way back home. In those days I was on a LURS committee and knew various high-ups in LU. They used to read my magazine!