Central Line Eastern Extensions

6.—PROVISION OF AUTOMATIC REVERSING FACILITIES WEST OF LEYTON.
(a) General.
A trailing crossover (No. 100) will be provided approximately 100 feet east of the tunnel portals west of Leyton for reversing from east to west.
During the period that the Central Line service is reversed from east to west at this point the eastbound road immediately east of this crossover will be used as a reversing siding, with a train berth, from the outlet signal (LD.5) to the stop board at the east end, of 420 feet. The eastbound road east of the reversing siding will also be made available for stabling a train in emergency, with a train berth of 390 feet.
Handworked trap points (No. 2), equipped with a switch lock, will be provided at the stop board to protect any train stabled east of the reversing siding.
Handworked trap points (No. 4), fitted with a switch lock, will also be provided on the westbound road to protect this road east of the points of the reversing crossover when trains are being worked into or out of Drapers' Field Depot.
While the automatic reversing of trains through No. 100 crossover is in operation (see sub-paragraph (b)), Nos. 2 and 4 trap points will be locked in the open position.
(b) Automatic operation of crossover.
The signalling and points will be arranged to operate automatically as follows :—
The eastbound home signal (LD.l) and the siding outlet signal (LD.5) will normally be in the Danger position, and No. 100 points will be normal. With the siding unoccupied (493B track clear), signal LD. I will clear when a train occupies the approaching track circuit 491 A. When the train has entered the siding and cleared the fouling track (493A), the points will reverse automatically, and the westbound starting signal (LD.5) will be lowered for the train to proceed on to the westbound road. When the departing train has cleared track BW, the points will be restored to the normal position, and the next eastbound train may then be signalled into the siding.
(c) Manual control of trap points and crossover.
A control lever, time-operated hand release switch, and a manual control switch having normal, off and reverse positions for No. 100 crossover, are located on the wall of the cutting at the east end of the crossover. Should it be necessary to hand-signal a train into or out of the siding east of the reversing siding, or to operate the trap points for train movements along the westbound road from Drapers' Field Depot, the following procedure must be observed :—
(i) To handsignal train into the siding.
Place the control lever as far back to normal as it will go, and place the manual control switch to the reverse position. Rotate the hand screw release handle in a clockwise direction until the " free " indication on the control lever is illuminated.
Place the control lever in the normal position.
The switch lock of No. 2 trap points will then be freed, and the points may be thrown to permit the train to move into the siding. It should be noted that when this operation is carried out, No. 100 points will be maintained in the reverse position to trap the train on to the westbound road, and unless the points are so reversed, the switch lock on No. 2 trap points will not be released.
(ii) To restore automatic operation. , -
The trap points must be opened after the train has been stabled.
The hand screw release handle must be rotated in an anti-clockwise direction to its fullest extent, and the control lever reversed.
No. 100 points will then be automatically thrown to the normal position, and eastbound trains may then work into the reversing siding and back to the westbound road in the usual manner.
(iii) To handsignal train out of the siding.
(a) If the " free " indication on the control lever is illuminated, the lever may be placed to the normal position
at once. If, however, it is not illuminated, the man deputed to operate the crossover road must ascertain that the manual
control switch is in the reverse position. If the visual is not illuminated, this may be due to the presence of an incoming
(eastbound) train ; the Operator must therefore wait until the eastbound train has arrived, when the control lever must
be placed as far as possible to the .normal position. When the train has departed westwards, the control lever must be
restored to the fully normal position, so that No. 100 points will be reversed, thereby permitting the release of the switch
lock on No. 2 trap points. •
If the visual is not illuminated and the operator has cause to suspect that there is a failure of the signalling apparatus, he must, after the lapse of three minutes (i.e., an adequate period to cover the running in time of an eastbound train), telephone to signal LD.l, and.if he receives a reply, inform the Driver of the train detained at the signal of his intention to effect a release by means of the hand screw release switch in order to handsignal a train out of the siding.
The operator must then effect the release of the control lever in accordance with the first paragraph of 6 (c/i).
(b) With the control lever fully normal, No. 2 switch lock may be released and the trap points closed to permit a train to be handsignalled out of the siding.
When the train has cleared No. 2 trap points, they must be opened again and the controUever must be reversed. If the time release switch has been used as above, it must be wound in an anti-clockwise direction to its fullest extent, and the outlet signal LD.5 will clear for the train to depart westwards.
(iv) To handsignal train along the westbound road from Drapers' Field Depot.
If the " free " indication on the control lever is illuminated, the lever may then be placed immediately to the fully normal position. If the indication is not illuminated, the operator must carry out the instructions laid down in sub-paragraph c (in I a).
When the control lever is normal the switch lock on No. 4 trap points will be released, and the trap points may be closed, and trains handsignalled on the westbound road. On completion of the shunting operations through No. 4 trap points, the points must be opened and the control lever pulled to the reverse position when the automatic working of the reversing crossover will once more come into operation.
(v) Manual control of No. 100 points.
In the event of it being necessary to operate No. 100 points other than as laid down for automatic operation, or in conjunction with shunt working through No. 2 or No. 4 trap points, this must be done by replacing the control lever to normal as shown in sub-paragraph (iii/tf) above. The points may then be operated by the use of the manual control switch.
It will not be possible to operate No. 100 crossover by the switch unless Nos. 2 and 4 trap points are in the normal (" open ") position.
The switch must always be returned to the " off " position after use as above, and before automatic operation is resumed.
(d) Telephone facilities.
Telephones will be provided in the Operator's hut as shown below :— (i) Automatic telephone ... ... RL. 5423.
(ii) Magneto type ... ...Stratford platform*
Control point at east end of No. 100 crossover (two instruments).
(iii) Central battery type ... ...Signal LD.5.
Signal LD.l (line arranged for two-way working).*
Lines marked thus * can be switched through to the control point at the east end of No. 100 crossover.
(e) Special switch control for automatic intermediate signal A.494.
In the event of a train failing in the tunnel on the westbound road between Leyton and Stratford, an assisting train in the rear may be used to move it. On account of the severe gradients approaching Stratford station, it is essential that the disabled train should be given a clear run into the station. For this purpose a special switch is provided in a locked box at Stratford station to extend the control of signal A.494 up to a point at overlap distance beyond the station starting signal A.490.
In the circumstances indicated above, the Station Master at Stratford, on receipt of advice from the L.P.T.B. Operating Department official responsible for the assisting move, must operate the switch to the open position, and maintain it in this position until the defective train has departed from Stratford station.

8. Why do LF2 and LF7 have splitting repeaters for LF3 and LF8? I can understand LF7 having splitting repeaters due to the need to provide unambiguous signal info to a freight train, but why LF2?

10. Another example of odd slotting is LG516a, slotted by LH46. Is this slot the same type of setup as the other slot?

12. Could LJ18 be cleared for movements over both 13 and 37 crossovers?