On October 21, 2018, Puyuma train 6432 (the train in the occurrence) of the Taiwan Railway Administration, MOTC (TRA) departed from Shulin Station bound for Taitung Station. As the train arrived at the right-turn transition curve on the fourth track at Xinma Station, Su’ao, at a speed of 140 km/h, the eighth carriage from the driver’s end of the train (toward the sea) overturned at location K89+251, causing all eight of the carriages of the train to derail. Four carriages overturned. Total 370 people on board, 18 fatal injuries, 17 serious injuries, 274 minor injuries, and 61 not injured.

The Executive Yuan had submitted the 6432 Puyuma investigation report on December 21, 2018. However, when the Legislative Yuan passed the Organization Act of the Taiwan Transportation Safety Board and the Transportation Occurrence Investigation Act on April 2, 2018, a subsidiary resolution requested that the Taiwan Transportation Safety Board (TTSB) should re-evaluate and review the report submitted by the Executive Yuan after being established. Also reviewed and interviewed the key evidence to clarify the systematic problems and root causes of the Puyuma occurrence. In response to the subsidiary resolution, the TTSB Board meeting passed a resolution immediately after the establishment of the TTSB on August 1, 2019 that the TTSB should provide necessary reinforcement to the investigation report of the Executive Yuan in accordance with Articles 3 and 6 of the Transportation Occurrence Investigation Act.

The TTSB carries out the investigative duties independently according to the Act, in addition, the investigation model is comparable to the high standards of aviation occurrence investigation (ICAO standards) and the spirit of openness. For the purpose of pertinence and collect relevant evidence, The TTSB invited relevant agencies/companies to participate in the investigation, including the Railway Bureau, Taiwan Railways Administration, Taiwan Railway Union, Nippon Sharyo, LTD., Taiwan Nabtesco Service Co., Ltd., Toshiba Electronic Components Taiwan Corporation, and Bombardier Transportation Taiwan Limited.

This investigative report includeed the following safety factors: the driver, the dispatcher, the mechanic, reporting of train malfunctions and anomalies, accession and management procedures for malfunctions and anomalies, ATP isolation procedures, train speed limit, communication procedures, man–machine interface (MMI), regular and random train maintenance at all levels, maintenance checklist and parts management mechanism, regulations in the supplier manuals, warranties and contracts, track maintenance, drivers work units, training and independent assessments for staff, TRA procedural manual, safe data use, medical examination system, drug use guidelines, emergency responses of attendants, response drills for staff, supplier’s system design, recorders, manual content, the supervisory authority of the Railway Bureau, cameras in the driver’s cab, passenger seat belts, tilting control system, air suspension, and the safety management system in railway operation agencies and institutions. This draft report has been approved by the 16^th Board Meeting on September 30, 2020. The final report of the investigation is released only after the Board has completed its initial review, review and representation of statement in accordance with legal procedures.

There were a total of 50 findings of the investigation, including direct causes attributed to the operation of the driver, the assistance of the dispatcher and the mechanics, etc. Get to the bottom of these causes were that the TRA failed to provide the driver, the mechanics and the dispatcher complete manuals and procedures to follow; also, the TRA failed to provide the driver and the mechanics complete trainings and checks, and there was no independent certification system that causing the staff to be unfamiliar with the system and operation of the train; besides, the TRA did not implement the established norms which resulted in ATP being quarantined illegally and train speeding; in addition, the TRA canceled the train parts replacement item and delayed the maintenance schedule for operational reasons, resulting in the forced shutdown and poor performance of the compressor.

In summary, the TTSB made a total of 27 recommendations to the Ministry of Transportation and Communications (MOTC), the Taiwan Railway Administration (TRA), and Sumitomo Corporation (Sumitomo), a Puyuma train supplier, for improvements in organization management, maintenance management, operation management, and train system design, etc. The TTSB will assist the Executive Yuan in following up on these recommendations in accordance with the Transportation Occurrence Investigation Act.

Vivi Yang, Executive Officer
Tel: 89127388-6217
Email:viviy2314@ttsb.gov.tw