Delay Attribution Board Process and Guidance …

1 Delay Attribution Board Floor 8 1 Eversholt Street London NW1 2DN Delay Attribution Board Process and Guidance Document 3 Y Code Application This Process and Guidance Document covers the appropriate application of Y Codes and should be read in conjunction with PGD2 Reactionary Delay Principles and Examples. Notes: Understanding the Attribution of reactionary Delay is critical for performance improvement purposes, particularly DPI analysis Delays outside the Guidance of the regulation policy or where excessive lateness is involved may be considered a new prime cause The use of the word Signaller should be considered as representing ARS/TRC etc The use of the word Unit should be considered to represent all forms of rolling stock The use of line blockage , can represent any incident that prevents that passage of trains Unit failure, flood, Cable theft etc.

2 Summary of codes: CODE CAUSE ABBREVIATION YA Lost path - regulated for train running less late REG-ONTIME YB Lost path - regulated for another later running train REG-LATE YC Lost path - following train running less late FOL-ONTIME YD Lost path - following another later running train FOL-LATE YE Waiting to/from single line TO S/LINE YG Regulated in accordance with Regulation Policy REG INSTRC YI Late arrival of booked inward stock INWD STOCK YJ Late arrival of booked train-crew INWD CREW YL Waiting passenger connections within connections policy.

3 Contingency plan or otherwise agreed by NR/TOC AUTHSD CON YM Special stop orders within the contingency plan or agreed by NR/TOC AUTHSD SSO YN Service Recovery- booked train crew, not available FIND CREW YO Waiting platform/station congestion/platform alteration PLATFORM YP Delays due to diversions from booked route or line DIVERSION YQ Passenger overcrowding caused by a train being of short-formation SHRT FRMD YR Tactical cancellation for service recovery not caused by late running SR CNCL YU Service Recovery- booked rolling stock, not available UNIT SWAPS YT Reactionary Delay to a train that is not leaving the network, by a train that is leaving the network NON NR INF YX Passenger overcrowding caused by Delay or cancellation of another train or its own late running OVER CRWD DESCRIPTIONS AND EXAMPLES YA Lost path - regulated for train running less late REG-ONTIME Train A is regulated because of its own lateness, for Train B.

4 The signaller has had to make a decision of preference between the two services and has done so to the less late train. The Delay should be attributed to the largest causal incident on Train A. Example: 1A23 is running 10 late and 2B10 is 2 late, both are going to arrive at a converging junction at the same time, the Signaller gives preference to Train 2B10 as it is less late. 2B10 1A23 YA 2B10, allocated to the largest causal incident on 1A23 ---------------------------------------- ---------------------------------------- ----------------------------------- YB Lost path regulated for another later running train REG-LATE Train A is the later train and is given preference over Train B.

5 The signaller has had to make a decision of preference between the two services and has done so to the more late train. The Delay should be attributed to the largest causal incident on Train A. Example: 1A23 is running 10 late and 2B10 is 2 late, both are going to arrive at a converging junction at the same time, the Signaller gives preference to 1A23 as it is an Express. 2B10 2B10 YB 1A23, allocated to the largest causal incident on 1A23 ---------------------------------------- ---------------------------------------- ----------------------------------- PGD3: Y Code Application Page 2 of 12 June 2017 Double Regulation Scenarios and Y Code Application 2C50 is held for 1A23 and then further held for 2B10 (Taking that the regulation is in line with the regulation policy for that location) Various lateness combinations to demonstrate appropriate Y Code application.

6 - 1A23 2B10 2C50 2C50 Delay - Y CODE Attribution 10 late 5 late RT Allocated as YB 1A23 and YB 2B10 10 late RT 5 late Allocated as YB 1A23 and YA 2B10 5 late 10 late RT Allocated as YB 1A23 and YB 2B10 RT 10 late 5 late Allocated as YA 1A23 and YB 2B10 RT 5 late 10 late Allocated as YA 1A23 and YA 2B10 In all cases the Y Codes for each regulation are allocated under normal reactionary Delay rules to the largest causal incident on the latest train at that point. To ascertain the Delay allocation for the two separate regulations each must be reviewed as a regulation event in their own right.

7 The regulation Delay due to 1A23 should be considered as taking the time 2C50 was booked across the junction to the time it would have crossed the junction once 1A23 had cleared. This is the time 1A23 passed the junction plus the junction margin. The Delay due to regulation with 2B10 would be the remainder of the Delay incurred by 2C50. Example 2C50 is delayed by 9 minutes regulated for 1A23 and then for 2B10 2C50 is booked over the junction at 15:00 1A23 passes at 15:03 2B10 passes at 15:06 2C50 finally passes at 15:09 Junction Margin is 2 minutes So Delay to 2C50 due to regulation with 1A23 = 5 minutes (It could have gone over the junction at 15.)

8 05 if not regulated again for 2B10) The remainder of Delay (9 mins total Delay less the 5 mins allocated to 1A23) is the Delay due to regulation with 2B10 Therefore a Delay of 4 minutes is due to 2B10 In the right hand diagram if 1A23 and 2B10 go across the junction at exactly the same time then 2C50 should be considered interacting with 1A23 only as being the train immediately in front. 2B10 going across (or not) potentially makes no difference to the Delay incurred by 2C50. 2B101A232C502B10 PGD3: Y Code Application Page 3 of 12 June 2017 YC Lost path - following train running - less late FOL-ONTIME Train A is following Train B because Train A is later and has lost its path.

9 In the Delay section the Signaller can make no decision. The Delay should be attributed to the largest causal incident on Train A. Example: 1A23 is running 10 late and 2B10 is 2 late. 1A23 is an Express and catches up to 2B10 (which it should be in front of) on a two track section and follows it until the next junction. The infrastructure precludes any Signaller intervention 2B101A23 1A23 YC 2B10, allocated to the largest causal incident on 1A23 ---------------------------------------- ---------------------------------------- ----------------------------------- YD Lost path - following another later running train FOL-LATE Train A is following Train B because Train B is late and has lost its path.

10 In the Delay section the Signaller can make no decision. The Delay should be attributed to the largest causal incident on Train B. Example: 1A23 is running 2 late and 2B10 is 10 late. 1A23 is an Express and catches up to 2B10 (running in booked order) on a two track section and follows it until the next junction. The infrastructure precludes any Signaller intervention 2B101A23 1A23 code YD - 2B10, allocated to the largest causal incident on 2B10 ---------------------------------------- ---------------------------------------- ----------------------------------- PGD3: Y Code Application Page 4 of 12 June 2017 YE Waiting to/from single line TO S/LINE Train A is waiting for Train B to clear a single line section of track.