Trial running and timetable proving

How does Trial running and timetable proving work, step by step?

1. 1

   Step 1: Define what trial running has to prove

   Entry criteria and exit criteria are agreed before trial running starts. The entry criteria confirm what must be complete - testing closed out, staff trained and competent, depots operational, procedures issued, outstanding items dispositioned. The exit criteria define what the railway must demonstrate: sustained delivery of the timetable, reliability at the level agreed, successful execution of the degraded-mode scenarios, and the closure of anything the period itself throws up. Both sets are agreed with the operator, the infrastructure manager and the assurance parties.

2. 2

   Step 2: Get the people ready before the trains run

   Drivers, signallers, controllers, station staff, maintenance staff and depot staff are trained and formally assessed as competent, and drivers gain route knowledge over the new infrastructure. Rosters are built for the full service, which is often the first test of whether enough people have been recruited and trained. Trial running is where an under-resourced or under-trained operation becomes visible, and there is no way to conceal it - the timetable simply does not get delivered.

3. 3

   Step 3: Prove the depot and the fleet

   The depot is exercised as the service demands: stabling, cleaning, fuelling or charging, maintenance examinations, fault rectification and the daily presentation of units to the timetable. Fleet availability and reliability are measured. Depots are frequently the last part of a project completed and the least tested, and a depot that cannot turn out the required number of units in the morning stops the railway just as effectively as a signalling fault.

4. 4

   Step 4: Run the timetable and measure it

   The full service is run to the intended timetable, day after day, without passengers. Punctuality, cancellations, turnaround times, dwell allowances, headways and the recovery of the service after a delay are measured against the criteria. Where the timetable proves undeliverable, the cause is identified - it may be the infrastructure, the fleet, the operating plan or the timetable itself - and the timetable is adjusted before opening rather than after. Better to change it now than to publish something the railway cannot achieve.

5. 5

   Step 5: Exercise degraded operation deliberately

   Faults are introduced and incidents simulated so that the degraded-mode procedures are actually used: equipment failures, a train stopped between stations, control system loss, station or platform closure, and the reversion arrangements that go with each. The measure is not only whether the immediate response is safe but whether the railway recovers to the timetable afterwards. Findings feed straight back into the procedures, and significant ones are re-exercised rather than simply written up.

6. 6

   Step 6: Run the major emergency exercises

   Full-scale exercises are run for the scenarios that matter most - evacuation, fire, a serious incident requiring the emergency services - usually with the emergency services taking part and often with volunteers standing in for passengers. These exercises test communication between organisations, command arrangements, access for responders and the practical usability of the evacuation routes. They are debriefed formally and the actions are tracked to closure like any other finding.

7. 7

   Step 7: Close out the findings and confirm the criteria are met

   Everything observed during trial running is logged, categorised and dispositioned: closed before opening, mitigated with an agreed operational restriction, or accepted into service with a plan. Performance against the exit criteria is assessed over the whole period rather than on the best week. The operator, the infrastructure manager and the assurance parties review the outcome together, and where the criteria are not met the period is extended - which is uncomfortable, and is the correct decision.

8. 8

   Step 8: Obtain entry into service authorisation

   Opening is a formal authorisation granted on the strength of the complete evidence base - design, construction, static testing, dynamic testing, integration testing, trial running, competence, procedures and the disposition of every outstanding item. It is a decision made by defined parties against defined criteria, not a certificate issued at the end of a construction contract. Because it sits at the end of a long dependency chain and cannot be brought forward by working harder, entry into service is the critical path on almost every railway project.