LAST STAGE OF SPECIAL TESTING PERIOD ON METRO LINE M4 BEGINS EXPERTS TO EXAMINE THE SYSTEM FOR TWO WEEKS IN PASSENGER OPERATION

Begun in mid-March, the special testing period where the automatic train control was tested with no train-attendant intervention first in the non-service areas of the terminuses and then without passengers on the entire line comes to its last stage. This third stage beginning on Monday 13 April 2015 will, for two weeks, examine the functioning of the system in passenger operation, i.e. how long it takes for the traffic controllers and station dispatchers to find and resolve any problems that might occur – modelling the ensuing full automatic operation of the line. The tests required for the final completion certificate mean that train attendants will remain on board but will intervene only after a given time elapses; it will be primarily the duty of dispatchers to resolve any problem that might occur. These tests will be carried out under the strictest safety supervision, yet minor disruptions might be expected in the two-week period.

As we have emphasized earlier, it should be noted that all the passengerless commissioning test runs of Metro Line 4 were carried out without drivers, just as the trains are now running in fully automatic mode in the on-going tests in traffic operation. Though the trains have temporary driver cabins, the only duty of the attendants seated in them is to supervise the movement of the trains and intervene in case a problem arises. The movement and operation of the trains are fully provided by the central automatic train control system, which underwent certification procedures involving prominent home and international firms and meet the highest safety levels. The final completion certificate is expected to be issued at the end of the year, until which experts will assess the results of the testing period, execute any changes in the system the assessment might deem necessary, and initiate similar examinations if so required. Thereafter, the driver cabins will be removed from the trains, and the vehicles will run under the safety supervision of only the central controllers and the station dispatchers.

During the testing stage commencing now and lasting until Sunday 26 April 2015, the experts of the National Transport Authority, BKV Zrt. and the systems-supplier Siemens will examine primarily how possible disruptions resulting from faults will affect the management of passenger service and the passengers themselves. As after shifting to the highest level of automation, the finding and resolving of any problem that might cause disruption will be the duty of the dispatchers. The vehicle attendants can only intervene after a few minutes in the event that the dispatchers are unable to resolve a problem arising, and, naturally, if the fault is safety critical and requires immediate action.

Metro Line 4 has been in operation in automatic mode for over a year without any safety critical fault, and by December 2014 it reached a 99.96% availability level, which is very strict by international standards. By the most probable scenario, passengers are going to encounter no other problem or event in this period that they have not met with previously. In the future, intervening experts will have to reach a problem site, perhaps in the tunnel, from the nearest station in case intervention is needed, and therefore, should a system failure occur during the current tests, the train or trains concerned will be stopped for the estimated average time, 8 minutes, required for this, thereby simulating possible future situations. When the time mentioned elapses, the train attendant switches to manual operation mode, and intervenes as required, while the experts supervising the tests follow and examine the effects of the fault on the station concerned and the entire line, and take the necessary measures to ensure the safety of the passengers. As a result, increased waiting times, passenger crowding and bottlenecks might occur with the brief stoppages of descending escalators, and, if made necessary by the tests, passengers might be asked to disembark vehicles.

According to international data, the number of fully automatic metros in the great cities of the world has reached 70, and of those with semi-automatic train control, as on Metro Lines 2 and 3 in Budapest, has reached 200, and another 30 automatic train control lines are being currently planned in various countries. A rapid increase in the number of automatic metro lines has been observed since 2007, which is a result of not only the long-term cost efficiency of automatic train control and larger passenger numbers it enables, but also the fact that automatic operation mode, by excluding the possibility of human failure, is much safer than traditional train control.

Should any disruption occur, we appreciate the understanding and patience of our passengers!

Budapest Municipality
Budapest Transport Centre (BKK)
BKV Zrt. / BKV Zrt. DBR Metro Project Directorate