KNKT releases preliminary investigation findings on Argo Bromo and KRL collision at Bekasi Timur station

Jakarta - The National Transportation Safety Committee ( KNKT) released preliminary investigation findings on the collision between Argo Bromo Anggrek and commuter trains at Bekasi Timur station on 27 April 2026. During a hearing with House of Representatives’ Fifth Commission, KNKT Chairman Soerjanto Tjahjoni presented factual data without conclusions, but highlighted key points. 1. Between Bekasi and Cikarang, both long-distance passenger and freight trains and commuter trains operate on the same track, with differences in operational speeds, service priorities, and stopping stations. 2. Discrepancies between scheduled and actual train timings, based on the Railway Operating Diagram ( Gapeka), have resulted in reduced headway between commuter and long-distance trains. 3. CCTV footage from Bekasi station shows that Argo Bromo Anggrek train no. 4B proceeded along Track 3 from Bekasi station towards Bekasi Timur station with J12 exit signal displaying green. 4. Field observations confirmed the presence of UB104 and B104 block signals before entering Bekasi Timur station. 5. Field observations of UB104 signal showed: a) vertical white light indicating ’ safe’; b) diagonal white light at 45 degrees indicating ’ caution’; c) horizontal white light indicating ’ stop’. Source: regulation no. 3 ( PD 3) on signal codes. 6. Interviews and recordings indicate that while train 4B traversed the section between Bekasi and Bekasi Timur stations, B104 signal displayed code 7 ( red aspect). 7. Around UB104 signal location, there are various light sources from residential homes and street lamps with intensity and colour similar to UB104 signal aspects. 8. Simulations conducted at Bekasi station’s equipment room and post-incident field simulations, with the scenario of train moving directly from Track 3 at Bekasi station and occupied track section 104BT, showed: a) J12 exit signal showing green ( code 5); b) UB104 repeating signal displaying horizontal white light ( code 9C3); c) B104 block signal showing red ( code 7). The signal aspect consistency was confirmed. The signalling system between Bekasi and Bekasi Timur uses Automatic Block System. Route formation from Track 3 Bekasi to Bekasi Timur ( Route 12T-14T): 1. J12 signal to Track 14T; 2. with the condition that tracks 13AT, 13BT, 13CT, 13DT, and 14T are clear. 9. Analysis of the locomotive data logger for Argo Bromo Anggrek train no. 4B on 27 April 2026 showed progressive braking: first service brake, then full service brake, followed by emergency brake application. 10. Based on interviews with the 4B Argo Bromo Anggrek crew, braking tactics were applied with due consideration for train safety… 11. The crew’s actions during hazardous operations comply with PT Kereta Api Indonesia’s ( Persero) Director regulation no. PER.U/KL.104/VII/4/KA-2023 on diesel locomotive and rail diesel train operations, 2023, part twelve, hazardous situation actions, article 40. 12. Communication services at Manggarai east control centre: a) east control centre manages east line trains, including commuter and locomotive-hauled services. b) east control centre has one radio lok PK S.1 console for communication with east line locomotive operators. c) commuter line east line radio communications are handled by south control centre using Sepura S.27 and Tait S.27 radios, depending on installed equipment. d) south control centre’s console includes five radios: radio lok PK S.23 ( south line locomotives), Sepura S.26 ( south line commuter trains), Tait S.26 ( south line commuter trains), Sepura S.27 ( east line commuter trains), and Tait S.27 ( east line commuter trains). 13. During the accident, the radios used were: • commuter line 5181 used Tait radio in S.27 ( south control centre) coverage; • commuter line 5568A used Sepura radio in S.27 ( south control centre) coverage; • Argo Bromo Anggrek train 4B used radio lok in S.1 ( east control centre) coverage. 14. Prior to the collision between Argo Bromo Anggrek train 4B ( Gambir - Surabaya Pasarturi) and commuter train 5568A ( Kampung Bandan - Cikarang) at Bekasi Timur station, commuter train 5181 ( Cikarang - Angke) had collision with a four-wheeled vehicle at a level crossing…