'Wrong way round' trains

[jimbo]

Is any effort made to keep the S stock 'right way round' in depots? For passengers, the wheelchair spaces are on the middle cars, which with S7 could be the 3/4 cars or 4/5 cars, depending on which end the 3-car section is. I suppose if the platform is close to train height, then access is easy to these, rather than the short hump section provided at some platforms alongside the wheelchair space car.

The Central Line used to try to right 'wrong way round trains' when A to D end coupling was required. Is this no longer important? Is any effort made to stable trains 'right way round' on lines where they can be turned in service?

[t697]

No effort made to keep S7s a particular way round.
The platform humps on platforms used by S7 trains are long enough to suit the declared wheelchair compatible doorways with the train either way round.
As mentioned above, some platforms comply without specific humps being added or with barely noticeable humps.

S8 trains are also reversible and timetabling turns some on the Watford triangle. No more trouble with stock shortage due to not enough units a particular way round to form into a train.

[castlebar]

I've always had a problem with "handed" stock
Over simplification leads to false economies
I remember many years ago the Picc lent some stock to the Northern, some of which had been 'turned' on the Kennington loop
Once back on the Picc, it was unusable until it was all turned on the Gloucester Road triangle.
A ridiculous waste of time and resources bearing in mind the Picc now has a loop at Heathrow rendering 'handed stock' a liability.

[t697]

Lots changed since that Picc/Northern lend;
- You can't run Picc trains on the Northern due to different signalling systems and vehicle gauging not checked.
- You can't turn Picc trains at the Triangle, due to different signalling systems and the Triangle area traction voltage now being nominal 750V which isn't good for 73TS equipment.
- Crossovers at Hammersmith have been removed.
- The Heathrow loop does now exist of course.

[towerman]

Wrong way trains could cause grief at Hainault in 62TS days.During the day there were a couple of turning paths Hainault-Leytonstone-Grange Hill,but on nights could end up with the situation of having a good train but one unit right way & one wrong way.Also if the depot ended up with too many wrong way trains,the Line Controller had to be told which trains were in service wrong way round in case of push outs.

[castlebar]

Jan 21, 2023 17:45:55 GMT towerman said:

Wrong way trains could cause grief at Hainault in 62TS days.During the day there were a couple of turning paths Hainault-Leytonstone-Grange Hill,but on nights could end up with the situation of having a good train but one unit right way & one wrong way.Also if the depot ended up with too many wrong way trains,the Line Controller had to be told which trains were in service wrong way round in case of push outs.

My point exactly

Quite how dumb do you have to be to order "handed stock" for a line with a loop at one end?

[t697]

I seem to recall that 1960TS as built was reversible and it was the rush into ordering 1962TS for the main build that gave the Central line non-reversible trains until 92TS.
A rush to replace Standard stock as a result of at least two factors:- Expected increased ridership due to BR Eastern Region electrification and resultant increased commuting into London. And the two serious fusing incidents with Standard stock at Redbridge and Holland Park in '58 and '60.

[croxleyn]

Could someone please enlighten me as to what characteristics make a train "handed"? Is it that the wheels wear differently to fit worn track profiles?

[Chris M]

AIUI it's about the electrical and air connectors in the coupler - reversible trains have duplicate connectors while handed trains do not. While the latter are obviously cheaper to build (and maybe maintain, I don't know) it does lead to significant operational inconveniences.

[100andthirty]

Jan 22, 2023 14:10:52 GMT Chris M said:

AIUI it's about the electrical and air connectors in the coupler - reversible trains have duplicate connectors while handed trains do not. While the latter are obviously cheaper to build (and maybe maintain, I don't know) it does lead to significant operational inconveniences.

On some of the older trains such as 1938 and 1959/62 tube stock, there were other constraints too. At autocoupler positions one end had a spring buffer and the other had a fixed buffer. The spring buffer protruded further from the underframe than the fixed buffer. As a result, if, as a result of a wrong way round train, two spring buffers tried to couple they were not all that compatible. What I don't remember is whether a coupling adaptor was needed in this situation or whether a 'mighty shove' would get the coupling made.

[100andthirty]

A feature of the 1972 mk1 stock on the Northern line was a novel solution to the reversible train requirement. In essence a UNDM on the 3-car could couple to wither the north or south cab on the 4 car depending on its orientation. There was a but........as far as I recall two three car units could couple to each other but the electrical systems wouldn't work.

[metman]

Yes that’s right. The main factor with anything is cost. To have trains which are not handed there needs to be a duplication of connections on each side of the coupler.

For example, when the A60/62 stock was delivered in 1961-63 they could couple either way round. This was very useful when trains were turned on the Watford triangle and when temporary formations were required as a result of collisions.

When the A stock was converted to one person operation in the 1980s the additional wiring required for the passenger alarms, communication equipment and a few other things I’ve probably forgotten the trains became handed and most middle cabs were not fitted out with the required door controls etc.

Fortunately for the Met there was quite an excess of stock so it was coped with although the occasional turning trip via the Watford Triangle was still used.

The same happened on the Bakerloo with the 1972 stock now handed. Both Mk1 and 2 stocks were designed with the Kennington loop in mind so that the uncoupling non driving motor could couple to either cab end of the four car portion. This helped out staff at Golders Green and Morden form up trains. Now the 1972 stock on the Bakerloo have their middle 33XX cab permanently confined to the middle of the train. The also operate wrong way round but that’s another story…..

[metman]

Jan 22, 2023 14:48:57 GMT 100andthirty said:

A feature of the 1972 mk1 stock on the Northern line was a novel solution to the reversible train requirement. In essence a UNDM on the 3-car could couple to wither the north or south cab on the 4 car depending on its orientation. There was a but........as far as I recall two three car units could couple to each other but the electrical systems wouldn't work.

We both replied at the same time!!

I often wondered if the two 3 car units could couple and operate, thanks for that information.

[t697]

Jan 22, 2023 14:42:36 GMT 100andthirty said:

On some of the older trains such as 1938 and 1959/62 tube stock, there were other constraints too. At autocoupler positions one end had a spring buffer and the other had a fixed buffer. The spring buffer protruded further from the underframe than the fixed buffer. As a result, if, as a result of a wrong way round train, two spring buffers tried to couple they were not all that compatible. What I don't remember is whether a coupling adaptor was needed in this situation or whether a 'mighty shove' would get the coupling made.

A memory jogger; The spring buffer was on the 'D' end and hence the necessary coupling adaptor was called a 'D-to-D'. Mechanical only, no through control or pipe.

[towerman]

On 62TS A to A ends could couple(using presspan shields)D to D ends needed an adaptor which I believe was carried in the 9*** car.

[croxleyn]

Wow! What detail - thanks to all respondents.

[jimbo]

Interesting photos of wedgelock automatic couplers with the protective 'dutch oven' cover removed to show electrical connecting studs. These couplers were introduced with 1938 tube stock when train electrical systems were simpler link. Contacts had to be duplicated for the prototype 1960 tube stock to allow for coupling to either end of another unit link.

Also handed cars showing D end to left, with spring, coupled to A end to right link. Coupler faces not at centre point between cars.

[miff]

Andy Barr, in his lecture to LT Museum Friends, mentioned care is still taken to keep the museum’s ‘38 unit the right way round when returning to base, even though there is now no other unit it could work with.

[100andthirty]

Another challenge, solved for the 1992 tube stock onwards was to incorporate communications grade contacts in the autocouplers. However with very high frequencies now in use for on-train comms systems on S stock I am glad there there are no autocouplers within the train.

[towerman]

When PEAs & public address were fitted to 56/59/62TS the integrity of the auto couplers weren’t trusted hence an inter unit jumper being fitted.

[100andthirty]

Jan 24, 2023 17:50:49 GMT towerman said:

When PEAs & public address were fitted to 56/59/62TS the integrity of the auto couplers weren’t trusted hence an inter unit jumper being fitted.

Sorry to disappoint. Those mods were carried out in a hurry and a conscious decision was made to use jumpers rather than re-engineer the autocoupler stud panels to increase the number of studs for the extra circuits.

[towerman]

I’m going by what I was told at Golders Green.The auto couplers were OK to use on 72 TS but not on the older stock.