On Saturday 30 May 2020, V/Line train 8185 was a scheduled service from Melbourne’s Southern Cross Station to Wendouree in suburban Ballarat. The train departed at its scheduled time of 2216[1] and stopped at several stations en-route, including Ballan. On the approach to Ballan, the train experienced a minor degree of wheel slide[2] during braking, but was able to stop normally. The driver reported light rain and gusty winds at this time.

Figure 1: Rail route from Melbourne to Ballarat and Wendouree

Source: Google Maps. Annotated by Chief Investigator, Transport Safety

Departing Ballan, the driver began to experience wheel slip[3] events during powering and as the journey progressed, instances of wheel slide during braking. The train’s event recorder detected that the Wheel Slip/Slide Protection system (WSP)[4] was active for about 75 per cent of the time in the first 5 km after departing Ballan.

On the approach to Ballarat, the driver reported having commenced braking slightly earlier than would normally be the case due to the wet and windy weather conditions. The train’s event recorder detected braking being initiated at 23:33:44, with the train 4.9 km from Ballarat Station and the train travelling at approximately 160 km/h[5]. After 6 s of braking, the train’s WSP system detected wheel slide. Two seconds later, operation of the train’s sanding valve for a period of 3 s was detected. At 23:33:56, the driver released the brake and then re-applied it 1 s later. The brake was again released at 23:34:04, with the train travelling at 141 km/h. Shortly before the brake was released, operation of the sanding valve for a further 5 s was recorded.

The train then coasted for 23 s at which point the driver again made a further brake application. At this point, the train was 3.1 km from Ballarat Station and travelling at approximately 160 km/h, its speed having increased on the downgrade. Four seconds later the train’s WSP detected wheel slide and the WSP remained in this state for the rest of the approach into Ballarat. Two seconds later, the sanding valve was again activated and remained operating for a period of 71 s.

At 23:35:35, and approximately 650 m from the intended stop at Ballarat Station, the train passed over Humffray St level crossing at about 117 km/h. It is likely that the flashing lights, bells and boom barriers were all operating when the train passed through the crossing but with reduced warning time. Fourteen seconds later, at 23:35:49, the driver applied the Emergency brake, with the train recorded as travelling at 99 km/h and 235 m from the intended stopping point. At approximately the same time, the train passed across a set of facing points, which were speed limited to 40 km/h,[6] and onto the southern track that lead to platform 1. The train passed through Ballarat Station at about 100 km/h.

Figure 2: Ballarat railway station locality and level crossings

Source: Google Maps. Annotated by Chief Investigator, Transport Safety

The train passed its intended stopping point at the western end of Ballarat station at 23:35:59, travelling through the Departure signal at Stop, and continued through Lydiard St railway crossing around 2 s later at a speed of 93 km/h. One second before the train passed through the crossing, the road traffic lights changed from showing a green indication to a flashing amber. However, the gates were still across the railway track rather than protecting the crossing from road traffic and were struck by the train (Figure 3). Approximately 49 s before the train passed through Lydiard St, CCTV recorded a group of three pedestrians passing over the crossing.

The train continued westwards, through a set of trailing points with a speed limit of 40 km/h and onto the main line, passing over Doveton St North level crossing at 23:36:18, 377 metres from its intended stopping point, and travelling at 73 km/h. It is likely that the flashing lights, bells and boom barriers were operating when the train passed through the crossing, but with reduced warning time. The train came to a stop approximately 600 metres west of its intended stopping point at 23:36:38.

Figure 3: VLocity 3VL70 having impacted the first gate and about to strike the second. Train is running from right-to-left

Source: V/Line Corporation

The driver at this point communicated with Centrol[7] to report the incident and arrange for an emergency response. The conductor who was in the rear driver’s cab moved forward along the train and then checked on the two passengers in the front carriage before checking on the driver.

Passengers and crew had been subjected to high lateral forces as the train negotiated the points. One passenger had been seated as the train arrived into Ballarat Station. This person indicated to the conductor that they were uninjured. The other passenger had been standing near an exit door as the train approached Ballarat Station. This person sustained head, back, and leg injuries and was taken off the train by emergency services and admitted to hospital.

Once the passengers were detrained, the conductor was also admitted to hospital for assessment and later discharged.

ContextTrack and gradientThe track between Melbourne and Wendouree is Class 1 (160 km/h) constructed on concrete sleepers, and was upgraded between Deer Park West Junction and Ballarat as part of Victoria’s Regional Fast Rail (RFR) project completed in 2006.

From about 6.5 km out, the track approaching Ballarat Railway Station is on an approximate 1-in-52 downgrade. This continues for around 4 km, then eases over a further 1.4 km to be slightly uphill (1:737) briefly, then at 1:383 (also up) along the station platform.

Lydiard St level crossingThe level crossing over Lydiard Street North is immediately adjacent to the west end of the Ballarat Railway Station platforms. A set of swing gates (Figure 4) that protected the crossing are a heritage-listed unique Victorian historical artefact, approximately a century old, and an element of the preserved station precinct. When required, they swing through 90 degrees across the road to permit the passage of rail traffic. They were interlocked with signalling and controlled from the Centrol train control facility in Melbourne.

Figure 4: Level crossing gates, Lydiard St North, Ballarat - southern road approach

Source: Pass Assets - Department of Transport (Vic)

Damage to level crossingVLocity 3VL70 impacted the gates at a speed of approximately 93 km/h (Figure 3) destroying the two gates forming the southern crossing barrier (Figure 5). Parts of the gate assembly were later found lodged in adjacent buildings.[8]

Figure 5: Remnants of damaged gate – southern side

Source: V/Line Corporation

Train informationV/Line service 8185 on the 30 May 2020 comprised 3VL70, a 3-car VLocity Diesel Multiple Unit (DMU) set consisting of, in the direction of travel, DM1270 (a powered car with driving cab), TM1370 (a powered intermediate car), and DM(D)1170 (a powered car with driving cab and toilet facilities with Disabled Access). The vehicles were designed, manufactured, and are maintained under contract, by Bombardier Australia. They operate at a maximum service speed of 160 km/h.

Figure 6: VLocity Diesel Multiple Unit

Source: V/Line Corporation

Traction power is provided by a turbo-charged, 559 kW, 6-cylinder diesel engine under each vehicle, driving both axles of the cab-end bogie of DM and DM(D) cars as well as the № 1-end bogie of the intermediate TM car (refer to Figure 7, powered bogies being shown in brown).

This tractive force is delivered from the engine via an automatic hydrodynamic transmission comprising a torque converter (low speed) and two hydraulic couplings for higher speed.[9] The hydrodynamic transmission delivers power through cardan shafts to a final drive unit on each of the two axles of the power bogies. During train braking, the transmission is used as a retarder to provide hydrodynamic braking, which is ‘blended’ with friction braking provided by electro-pneumatic (EP) disc brakes on each axle.

VLocity DMUs are equipped with a Wheel Slip/Slide protection system (WSP) to optimise traction and braking levels and prevent damage to wheels and track in cases of reduced adhesion conditions. The WSP system functions such that:

• In the event of wheel slip being detected (powered axles are rotating faster than non-powered axles), engine speed and tractive effort are automatically reduced. Upon correction of the wheel slip, the system will re-apply tractive power according to the train driver’s power control (throttle) setting. Any such reduced engine output on an affected vehicle will be evident to the train driver from engine tachometer indications and a wheel slip warning light on the control panel. The wheel slip warning light will extinguish when adhesion is regained. Sanding may be automatically applied, and if so, a separate warning light will be displayed.
• In the event of wheel slide being detected in braking, brake cylinder pressure will be reduced (and hydrodynamic braking terminated) to regain optimum braking effort for the available adhesion. Sand may be automatically applied to the rail. Once the wheel slide has been corrected, the system will reinstate braking effort according to the train driver’s brake control setting.

Sanding SystemVLocity DMUs are fitted with a sanding system to apply sand to the rail head to improve the friction between the wheels and rail in low adhesion conditions. Sand can be applied automatically by the WSP system or manually by the driver using a foot pedal. Sanders are located at the front and rear of the set, and the TM cars are not equipped for sanding (Figure 7).

Figure 7: VLocity DMU traction and sanding arrangement

Source: Chief Investigator, Transport Safety

If the train is under power, sand is applied to the rear of the lead bogie of the DM car and in front of the last bogie at the rear of the train (DMD car in this case). Under braking, sand is applied behind the trailing axle of the lead bogie at the front of the train (DM car in this case).

Event recorderThe train was equipped with a Faiveley Transport VM-40 Event Recorder that logs 48 digital and 20 analogue parameters from the VLocity subsystems and equipment. Parameters of interest include:

• driver power and brake controller demand
• brake cylinder pressure
• axle velocity
• calculated train velocity
• sanding
• Wheel Slip/Slide protection system activation
• train location and time from an on-board GPS[10] receiver.

VLocity damageThe front of the lead carriage (1270) was significantly damaged, particularly the windscreen (Figure 8) and the passengers’ window where parts of the gate impacted the left side of the carriage (Figure 9).

Figure 8: VLocity car 1270 – impact damage to front of train

Source: Chief Investigator, Transport Safety

Figure 9: VLocity car 1270 damage to passenger side window from impact of gate debris

Source: Chief Investigator, Transport Safety

WeatherThe Bureau of Meteorology station at Ballarat Aerodrome recorded an air temperature of 9.0 °C and a relative humidity of 90 per cent at 2330 on 30 May 2020. Wind was from the north at 33km/h, gusting to 42 km/h and a light drizzle fell between 2300 and 2330 (0.2mm).

Safety actionAs a result of testing, performance issues with the sanding system on VLocity 3VL70 were identified and Bombardier has subsequently undertaken fleet-wide testing of VLocity sanders and performed remedial action where required.

Further investigationTo date, the ATSB has:

• carried out inspections of rollingstock and testing of the brake and sander operation
• carried out analysis of event recorder data
• conducted interviews with train crew
• examined evidence around track geometry and rail head condition.

The investigation is continuing and will include the review and examination of:

• operation and maintenance of the VLocity sanders
• evidence in relation to rail condition and wheel/rail interface
• dynamic performance of the braking system
• train operation and performance.

Should a critical safety issue be identified during the course of the investigation, the ATSB will immediately notify relevant parties so appropriate and timely safety action can be taken.

A final report will be released at the conclusion of the investigation.

AcknowledgementsThe ATSB acknowledges the cooperation received from V/Line Corporation and Bombardier during the initial investigation.