Central Line eastern extension signal style

[russe]

gallery62603.fotopic.net/p51705622.html is Fairlop, looking towards Hainhault. (I've informed Mike Morant on the location.)

What is the thing between the LL55 numberplate and the distant disc?

Russ

[tubeprune]

Would it be an illuminated "A" sign to indicate the frame was in auto? I think Fairlop had a ground frame at that time. It must have been slotted to Hainault in some way. [wanders away trying to remember how it would work].

[Harsig]

It was indeed an "A" sign. The relevant paragraph in the yellow peril (21/1948 or Eastern Region Instruction No 3067) reads:

20 "A" Signs

"A" signs will be provided at the following signals:

(a) LM599^B & LL55 (illuminated when the Inner Rail control lever (No 8) and the Inner Rail king lever at Hainault Signal Box are reversed)
(b) LM606^A, LM606^B & LM604 (illuminated when the Outer Rail control lever (No 9) is reversed).

Central Line Eastern Extension Diagrams

[russe]

Thanks guys. What would be the purpose of indicating (the illuminated "A" sign) that Hainhault's frame was in auto?

And, on the outer rail, what would be the purpose, having departed from Hainhault, of the "A" signs on LM606^A, LM606^B and LM604?

Russ

P.S. Here's a slightly better scan kindly provided by Mike Morant, of the signal part of the picture, showing the wording on the distant plate:

[Oracle]

Is that a Distant disc-type signal (black-on-yellow)?

[Deleted]

Jul 16, 2008 15:35:45 GMT @russe said:

Thanks guys. What would be the purpose of indicating (the illuminated "A" sign) that Hainhault's frame was in auto?

And, on the outer rail, what would be the purpose, having departed from Hainhault, of the "A" signs on LM606^A, LM606^B and LM604?

Certainly at the time (don't know to what extent it still does), Underground practice distinguished between 'Automatic' and 'Controlled' signals, and AIUI different procedures (i.e. rules) applied, certainly under some circumstances.
The illuminated A was to indicate that the signal was to be treated as an automatic signal, rather than a controlled one (which would have an associated signalman).

[russe]

Jul 16, 2008 16:35:31 GMT Oracle said:

Is that a Distant disc-type signal (black-on-yellow)?

Yes, and yes, they were black on yellow. A glimpse at Harsig's Central Line Eastern Extension diagrams shows a large number of them, some of them being on their own posts. They are the equivalent of a repeater. The Northern Line extensions 1931-41 also show them. According to the signalbox site, "These were only provided on lines which were also traversed by steam-hauled trains, because the LT-style signalling did not otherwise afford sufficient braking distance."

As per normal practice for ground disc signals, I think all of them were floodlit.

Russ

[mrfs42]

Jul 16, 2008 17:37:55 GMT @russe said:

Jul 16, 2008 16:35:31 GMT Oracle said:

Is that a Distant disc-type signal (black-on-yellow)?

They are the equivalent of a repeater.
As per normal practice for ground disc signals, I think all of them were floodlit.

Indeed they were all floodlit; however they were a *bit* more than a repeater - the appropriate yellow perils enumerate all the signals that need to be off for a distant to clear. In effect a distant repeated several sticks; and to further complicate matters there are standalone distants - Hainault in the photo; other places had a mix of 'outer', 'intermediate' and 'inner' distants. It all depends on what controlled signals and what frame controlled the signals in the necessary braking distance.

And, on the outer rail, what would be the purpose, having departed from Hainhault, of the "A" signs on LM606A, LM606B and LM604?

Belt-and-braces, I suspect. In the case of LM604 the groundframe could be opened after a train has passed over the relevant connections into the goods yard and be stood at the platform; in the case of LM606^{A or B}, I suspect that the 'A' light out would indicate that 'Fairlop is under local control' but the lack of the marker light would further indicate 'local control has been given but no route has yet been set'.

I can't look at my collection of yellow perils as the LU library currently has someone asleep in it. Otherwise I could look further into the wording, rather than the facile paraphrase above.

[railtechnician]

Jul 16, 2008 23:42:17 GMT mrfs42 said:

Jul 16, 2008 17:37:55 GMT @russe said:

They are the equivalent of a repeater.
As per normal practice for ground disc signals, I think all of them were floodlit.

Indeed they were all floodlit; however they were a *bit* more than a repeater - the appropriate yellow perils enumerate all the signals that need to be off for a distant to clear. In effect a distant repeated several sticks; and to further complicate matters there are standalone distants

This is also true with current colour light repeating signals in some areas which repeat multiple sticks, other than those repeating multiple home signals.

[mrfs42]

Very true - but wouldn't that be reflected in the signals ID plate eg R 896^A 896^B B4 (not an actual example, as the former signals would have been at opposite ends of current and former Met. territory)? I've seen lots of examples in yellow perils where (at least in the paperwork) the 'R' of the repeater spans three lines - an example off the top of my head was on the Bakerloo coming off the Stanmore branch into Baker Street, which I seem to remember repeated most of the homes and the controlled signal and I think there was one in the opposite direction that repeated two routes - one straight on, the other through the diverging route at the junction towards the approach lit auto. I may be conflating and misremebering the peril for the new IMR during the construction phase and the peril for the passenger opening.

What makes the distant plates interesting is that the plate was purely geographical; the sticks repeated (or controlling) the distants were only enumerated in paperwork, rather than at the signal itself.

[Deleted]

According to the 1969 General Signal Regulations, an illuminated "A" sign indicated that a controlled signal is operating as, and 'may be regarded as' an automatic signal.

The disc type distant signals were provided (on the Central, Northern and Metropolitan lines) AIUI for BR (steam) freight trains, which expected/wanted/needed (proper) distant signals (to provide the required baking distance), on what were otherwise purely Underground lines (signalled to Underground standards, and normally only worked by, Underground trains), where practice did not include 'distant' signals (as such), only repeater signals where necessary.

[Deleted]

Jul 16, 2008 23:42:17 GMT mrfs42 said:

Belt-and-braces, I suspect. In the case of LM604 the groundframe could be opened after a train has passed over the relevant connections into the goods yard and be stood at the platform; in the case of LM606^{A or B}, I suspect that the 'A' light out would indicate that 'Fairlop is under local control' but the lack of the marker light would further indicate 'local control has been given but no route has yet been set'.

I can't look at my collection of yellow perils as the LU library currently has someone asleep in it. Otherwise I could look further into the wording, rather than the facile paraphrase above.

mandgc (RIP) once posted the relevant snippet from a peril on the forum, describing the marker lights at Fairlop.

Channeling COLIN:

www.geocities.com/idsmesig/Signals/FailopLM1948.jpg

mandgc said:

Fairlop Diagram -
When the Ground Frame was in use the Outer Rail signals LM 606A and 606B were extinguished, the train stops lowered (to avoid delay during shunting on the Running line ) and the Marker lights "in the form of a cross" illuminated ( which authorised the Driver to pass the signals for Shunting purposes.

(from THIS THREAD)

[russe]

Notwithstanding the provision of the distant discs to cater for the extra braking distances for freight trains, can I assume that non-LT trains working the Central Line eastern extension were required to be fitted with tripcock gear?

Russ

[Oracle]

As being discussed at the moment on SEmG, they were I think all required. That meant that the small number of J15s at Stratford were so fitted as well as Class 15 BTH (some were fitted for use on the Northern freights) although I am not sure about any Class 16s at Stratford. Also, the DMUs used on the Epping services.

[Oracle]

If it was a steam loco, J15s left Stratford Shed in 1962 I think. British Thomson-Houston Type 1s, later Clas 15 under TOPS, came in instead.

[mrfs42]

A standard gauge BR steam train in 1969 would be impossible, surely?

[Deleted]

Oct 4, 2008 23:11:37 GMT mrfs42 said:

A standard gauge BR steam train in 1969 would be impossible, surely?

True. LU were still running steam locos on ballast trains in 1969, but steam had finished on BR by then.

[mrfs42]

Hmm... Did any of the panniers ever make it out to the eastern end of the Central, I wonder?

Even it was a highly indirect route?

[Oracle]

DMUs were used for staff BR trains, and somewhere I have noted whether they had tripcocks fitted...some did of course for the Marylebone services. These staff trains would have been double-manned I would imagine, left over from steam days, plus there would have been a Guard. I can imagine the secondman (ne Fireman) would be able to and want to bunk off.

[roythebus]

The same type of distants were to be found on the Met north of Harrow. IIRC, the distant, following BR practice, would only clear if all the stop signals at the station ahead were clear.

Freight trains at that time were usually unbraked and needed a lot of stopping, whether steam or diesel hauled. They relied on the loco and brake van to provide the stopping! In such cases, if the trip cock operated, it would be rather ineffective. I speak from experience.

[mrfs42]

Feb 13, 2009 22:50:23 GMT roythebus said:

The same type of distants were to be found on the Met north of Harrow. IIRC, the distant, following BR practice, would only clear if all the stop signals at the station ahead were clear.

Indeed, the 'yellow perils' of the time enumerate exactly which signals need to lowered beforehand - eg. Loughton Outer (under LS.659) lowered when LS.659, LT.28, LT.26 (to No. 24 platform road), LT.20A, LT.19 and LT.47 are lowered. [from Supp to TC 36/1949 - extension to Epping (must tidy it up, before AI comments...)]

Feb 13, 2009 22:50:23 GMT roythebus said:

Freight trains at that time were usually unbraked and needed a lot of stopping, whether steam or diesel hauled. They relied on the loco and brake van to provide the stopping! In such cases, if the trip cock operated, it would be rather ineffective. I speak from experience.

Trip cock on air [1] or vac.? Even with the GWRs <spit, spit, spittity spit> extra 4" of mercury the vac was still a pants brake. (Thinking of panniers here)....

[1] twin or single Westinghouse is immaterial - though the Central would have have twin-bag vac. DMUs.. ;D