KNKT Reveals Three Causes of Argo Bromo Anggrek vs KRL Collision, No Mention of Taxis

Jakarta, CNBC Indonesia – The National Transportation Safety Committee (KNKT) has released interim findings from its investigation into the collision between the Argo Bromo Anggrek train and the KRL Commuter Line on the Kampung Bandan–Cikarang route at Bekasi Timur station on 27 April. KNKT Chair Soerjanto Tjahjono said the causes were not tied to the alleged involvement of the Green SM taxi or taxis, but rather an anomaly in signalling between Bekasi Station and Bekasi Timur Station, communication problems, and a lack of discipline among rail traffic controllers. ‘One cause is that the signal leaving Bekasi Station could not detect train 5568A at Bekasi Timur station. There were also obstructions to lighting on the repeater signal and communication problems contributing to the accident,’ Soerjanto said at a parliamentary hearing with Commission V of the Indonesian DPR on Thursday 21 May 2026. He explained that simulations conducted by KNKT and colleagues show that the signal leaving Bekasi Station indicated a safe aspect (green light). The repeater signal indicated an unsafe aspect (a flat-line signal), and the block signal likewise showed an unsafe aspect (red). In reality, the signal leaving Bekasi should have shown a cautious aspect (yellow) if the ahead signal still indicated an unsafe indication (red). Not only that, the driver of the Argo Bromo Anggrek also had difficulty seeing the repeater signal in the Bekasi–Bekasi Timur sector because lighting from residential houses interfered with perception. ‘In-cab in the locomotive, and likewise in the KRL cabin, we observed the night conditions; the driver had difficulty seeing the repeater signal due to illumination from markets and houses along the tracks. The light from residences and street lighting, with intensity and colour resembling the repeater signal, created confusion.’ The simulation also showed that the communications used by each train’s crew were via radio. ‘KA 5181 used a Tait radio and was in the S.27 (PK Selatan) communications region; KA 5568A used a Sepura radio and was in the S.27 (PK Selatan) region; and KA 4B used locomotive radio in the S.1 (PK Timur) region,’ he explained. Through the simulation KNKT therefore preliminarily indicated that an anomaly in Bekasi Station signalling existed, whereby the exit signal from Bekasi Station did not detect the subsequent signals and the position of 5568A which was stopped normally at Bekasi Timur Station. In addition, obstructions around the repeater signal in the Bekasi and Bekasi Timur sectors, as well as radio communication interference between trains and the station controllers, were identified as preliminary causes of the Bekasi Timur incident.