Beritasatu, Bengkulu – Brake failure and driving negligence were suspected to be the cause of the Sriwijaya bus accident on Monday that killed 35 people in Pagar Alam, South Sumatra, recent investigation showed.
Following their discovery that there was no indication of braking at the scene, the National Transportation Safety Committee, or KNKT, inspected the vehicles and drivers of the Sriwijaya Express bus fleet in the Sungai Hitam area, Central Bengkulu, on Thursday.
KNKT investigation team leader, Ahmad Wilda, said a witness had testified that the bus was driving at high speed on the downhill before it plunged into a ravine. This failure to comply with the existing safety procedure – in which a vehicle should move at a low gear and speed on a steep downhill – led to the brake malfunction.
"The accident was not because of overcapacity, but a faulty brake. The bus plunged into the [150-meter deep] ravine because of a brake failure," Ahmad said on Thursday.
With the current death toll of 35 and 13 injured, the bus in question was reported to have been overcrowded.
Manifest of the fatal bus revealed that it was supposed to have 27 passengers on board when it departed from the Sentiong terminal in Bengkulu, bound for Palembang, South Sumatra.
However, on its way, there was an increase in passengers from Central Bengkulu and Kepahiang. Amid the conflicting reports on the number of passengers, there were concerned that six more passengers remain missing.
Thorough investigation involving several other teams was also carried out to uncover the country's worst road accident in 2019.
A joint SAR team between the National Police (Polri), the National Search and Rescue Agency (Basarnas) and the Indonesian Military (TNI) had successfully retrieved a part of the bus wreckage including the car engine from the Lematan River.
Sriwijaya Express management had temporarily halted their operation since Monday to focus on the evacuation as well.
For future precautions, Bengkulu Transportation Agency, or Dishub, also maintained a tight surveillance over both inter and intra-provincial buses in the province.
"We are maintaining a tight surveillance over these buses – specifically the aging buses that are still in operation – to assure their roadworthiness and prevent a similar accident," Bengkulu Dishub head Darpinudin said.