Central Line eastern extension signal style

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].

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:

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).

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.

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.

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



(from THIS THREAD)

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.

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

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?

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.