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Rail Safety Investigation Report No 2011/03

End-of-Track Overruns

Metro Trains Melbourne

Pakenham and Sandringham Sidings

09 March 2011

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TABLE OF CONTENTS

The Chief Investigator 5

Executive Summary 7

1. Pakenham Incident 9

1.1 Circumstances 9

1.2 Train driver 10

1.3 The train 10

1.4 Sequence of events 11

1.5 Infrastructure 12

1.6 Environment 15

2. Sandringham Incident 17

2.1 Circumstances 17

2.2 Train driver 19

2.3 The train 19

2.4 Sequence of events 19

2.5 Infrastructure 21

2.6 Environment 22

3. Research pertaining to both incidents 23

3.1 Siemens Electric Multiple Unit 23

3.2 End-of-track protection 23

3.3 Regulatory regime 27

3.4 MTM risk management 28

4. Analysis 29

4.1 The incidents 29

4.2 Train operation 29

4.3 Train braking performance 29

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4.4 End of track protection 29

4.5 Risk management 30

4.6 Application of VRIOG Standards 30

5. Conclusions 31

5.1 Findings 31

5.2 Contributing factors 31

6. Safety Actions 33

6.1 Safety Actions taken since the event 33

6.2 Recommended Safety Actions 33

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THE CHIEF INVESTIGATOR

The Chief Investigator, Transport Safety is a statutory position under Part 7 of the Transport Integration Act 2010. The objective of the position is to seek to improve transport safety by providing for the independent no-blame investigation of transport safety matters consistent with the vision statement and the transport system objectives. The primary focus of an investigation is to determine what factors caused the incident, rather than apportion blame for the incident, and to identify issues that may require review, monitoring or further consideration. In conducting investigations, the Chief Investigator will apply the principles of ‘just culture’ and use a methodology based on systemic investigation models. The Chief Investigator is required to report the results of an investigation to the Minister for Public Transport or the Minister for Ports. However, before submitting the results of an investigation to the Minister, the Chief Investigator must consult in accordance with section 85A of the Transport (Compliance and Miscellaneous) Act 1983. The Chief Investigator is not subject to the direction or control of the Minister in performing or exercising his or her functions or powers, but the Minister may direct the Chief Investigator to investigate a transport safety matter.

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EXECUTIVE SUMMARY

On Wednesday 9 March 2011, trains at Pakenham and Sandringham overran the end of the track and derailed. In both instances:

The trains were being stabled and were not conveying passengers at the time of derailment.

Significant damage was caused to infrastructure as well as to the trains involved.

There were no reported injuries.

The trains comprised two Siemens three-car sets forming six-car trains.

The investigation found that in both incidents the trains were travelling at speeds exceeding that permitted in the sidings, low adhesion conditions existed, braking performance was less than expected by the drivers and end-of-track protection was ineffective. Neither train was fitted with sanders to assist braking in low adhesion conditions. Since the incidents, Metro Trains Melbourne (MTM) has:

1. Issued alerts to train drivers regarding their obligation to adhere to posted speeds.

2. Completed a risk review of all stabling sidings to inform future infrastructure works at sidings, including end-of-track protection.

3. At Sandringham – installed steel buffer-stops at the end of siding tracks 1 and 2.

4. At Pakenham siding track 5 – relocated the catenary support structure struck by the derailed train to a position clear of the overrun zone.

5. Completed the installation of sanders on all Siemens trains, including the two six-car sets involved in these incidents.

This investigation makes recommendations in the areas of train driver supervision.

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1. PAKENHAM INCIDENT

1.1 Circumstances

At about 1913, train № 4629 running the 1757 service from Flinders Street Station arrived at Pakenham railway station platform 2. Shortly thereafter, the empty train was moved from the platform and into the yard to stable in dead-end track 5.

Figure 1 – Pakenham track layout and incident diagram

At about 1920, the train occupied track 5 and failed to stop, overrunning the end-of-track by more than 13 metres, destroying the timber baulks, and dislodging an overhead wire1 support stanchion from its concrete footing by approximately 5 metres. The stanchion was deformed and twisted around the leading end of the train. The overhead contact wire was dislodged and fell to lie across the top of the train. All wheels of the train’s leading bogie were derailed and the fibreglass lower structure of the leading end and ancillary equipment located behind it sustained significant impact damage (see Figure 2). The train windscreen and some intercar2 components were also damaged or destroyed.

Figure 2 – Damage to the front end of the train and leading bogie

1 The energised overhead electrical contact wire. 2 Between passenger cars.

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1.2 Train driver

The driver of train № 4629 was considered to be fit for duty and was current with regard to the required operating competencies. After arriving at Pakenham, he changed to the opposite-end driving cab and ran the empty train out of the platform (towards Melbourne) to position it beyond shunting signal 8 (see Figure 1). He changed ends again, and with the authority conveyed by the shunting signal, ran the train into the stabling yard to track 5. He stated that as he moved toward the yard he was momentarily distracted as a Down V/Line train passed him on the parallel track and he had to check his speed while crossing the Main Street level crossing. He stated that his train “...reacted to the braking as I would expect it to...” When the train was fully in track 5 and approximately two or three car-lengths from the baulks he applied braking in position 2 and the train did not brake at a rate consistent with his expectations and did not slow down. He increased the braking effort but again the train did not respond. At about one car-length from the baulks he applied emergency braking “...and felt the train take off.” At this point the driver realised the train would overrun the end-of-track and braced himself for collision with the stanchion. The driver reported that he attempted to place an emergency radio call to Metrol3 but without success. He then made contact on a company-supplied mobile phone to advise Metrol of the incident. He subsequently used the phone to call the Pakenham railway station, receiving no response. Aware there was a dislodged overhead contact wire lying across the train, the driver remained inside his cab until advised that the power was off. He later returned to the cab to activate the train’s data recorder. The driver also advised that at the time of this incident he was distracted by a personal domestic matter.

1.3 The train

1.3.1 General

The six-car train consisted of Siemens car-sets 815M-2558T-816M and 817M-2559T-818M. Total consist length was 143.6 metres and total mass was 241.6 tonnes. The braking system of Siemens trains comprises electro-dynamic (ED) and electro-pneumatic (EP) elements. To assist the management of wheel slip-and-slide in low adhesion conditions, the braking control system includes a wheelslip/wheelslide protection (WSP) feature that activates automatically upon detecting a loss of traction when under power or upon the onset of wheelslide under braking. The train was not yet fitted with sanding devices to assist braking in low adhesion conditions (see section 3.1). Post-incident inspection did not identify any defect relevant to the incident.

3 MTM’s control centre for train operation on the metropolitan passenger network.

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1.3.2 Data recorder

Siemens trains are fitted with a Traction Control Unit (TCU)4 that incorporates a diagnostic facility for maintenance support as well as limited capacity for event recording. Following any out-of-course operating event, the train driver is required to capture data recorded over about the last kilometre of distance travelled by pressing a button mounted on the driver’s control console. If this button is not activated following an event, data recorded up to that point will be progressively overwritten when the train next moves. Operating information recorded by the system includes:

Operating mode (e.g. powering, braking, direction of travel)

Status of braking control equipment (including degree of braking called-for by the driver)

Speed of train (estimated from axle speeds).

The system does not measure or record brake cylinder pressure.

1.4 Sequence of events

After arrival at Pakenham railway station platform 2 and discharging passengers, the train was run back out of the platform on the Up track5, stopping behind shunting signal 8 (Figure 1). After receiving the requisite Low Speed indication (maximum speed 15 km/h) on this signal, the train proceeded into track 5. Analysis of the train’s recorder data reveals the following sequence:

1. After moving off from the signal, the train is shown to have accelerated to around 40 km/h over a distance of approximately 80 metres. The train then coasted for about 100 metres, reaching an indicated speed of 43 km/h. Over the next 250 metres a number of brake applications were made, gradually reducing the speed of the train.

2. The final braking sequence, initially using only brake positions 1 and 2, was commenced about 160 metres before the baulks at a speed of about 31 km/h. The initial evidence of a loss of wheel-rail adhesion was seen on motor car DM815 about 30 metres later at a speed of 27 km/h.

3. A brake application to braking position 3 was made about 70 metres prior to the baulks with the train at a speed of about 20 km/h, and at about this time there was evidence of a loss of adhesion on other DM (Driving Motor) cars, and a transition from ED to EP braking (this transition occurs automatically). This brake application is shown to be incrementally increased until attaining full service about 40 metres prior to the baulks. An emergency application was then made 25 to 30 metres before the baulks and about 40 metres before the train came to a stand.

4. Once wheel-rail adhesion was lost—initially on DM815 and later on the other DM cars—there was evidence of the presence of ongoing relative longitudinal creep between wheels and rail, suggesting continuing low levels of adhesion.

4 A microprocessor-based device that monitors and controls aspects of the train’s traction and braking functionality. 5 On double-line, the Up track conveys rail traffic toward Melbourne.

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5. For the final stages of deceleration prior to impact, with braking first at Full Service and then Emergency positions, the calculated average deceleration was about 0.2 m/s².

Significantly, the rate of speed retardation indicated during this attempt to slow the train as it approached the end of the siding was somewhat less than that obtained earlier when the train arrived at Pakenham railway station and was bought to a stand at platform 2 without incident. At the end of track 5 the train struck and destroyed the timber baulks secured across the rails and continued for approximately 8.6 metres through ballast before striking and riding up onto the concrete foundation block of an ‘overhead’ stanchion6 located directly in its path. The train came to rest with the forward end of the train astride and projecting almost 5 meters beyond the concrete block, with the distorted steel stanchion draped around its leading end. Although the lead DM car was derailed and its lead bogie ran through ballast and could not therefore provide accurate evidence of distance after leaving the rails, an analysis of distance is afforded by cross-referencing the data from other DM cars in the train.

1.5 Infrastructure

1.5.1 Track construction and geometry

The track geometry category that defines the structure of track 5 in the Pakenham railway station yard is siding track. It consisted of second-hand jointed rail dog-spiked to timber sleepers and was in average condition. It is specified for a maximum speed of 15 km/h. Track geometry measurements for the final 315 metres of the siding were made post-incident by MTM and supplied to the investigation. All aspects of the track geometry were found to be within specified tolerances for 15 km/h siding track, except for gauge being tight by up to 9 mm for short distances at two locations – about 140 metres and 40 metres respectively from the end-of-track. Timber baulks were provided as the end-of-track protection and were overridden by the train.

1.5.2 Rail head geometry

A substantial length of the rail in the siding was significantly head-worn, and in some locations the area of wheel-rail contact indicated that this rail had been transposed7. This is not unusual for second-hand rail that may have been cascaded from premium to secondary use or swapped in-situ to equalise rail head wear. This advanced head-wear had resulted in a flat rail head profile that provided opportunity for water to pool and in some sections two points of wheel contact (see Figure 3).

6 A vertical stanchion supporting one end of the overhead contact wire gantry. 7 Moved from being a left-hand or right-hand rail (in either direction of travel) to being the opposite. In both cases, the

‘gauge face’ (or running edge) of the rail becomes the ‘field face’ and vice-versa.

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Figure 3 – View of the rail head at Pakenham train stabling siding track 5

Independent assessment of wheel-rail interface at Pakenham and Sandringham The investigation obtained from MTM the results of an independent assessment by a consulting track infrastructure engineer of the nature of the interface between the wheel treads of both train sets and the rail head surfaces at both the Pakenham and Sandringham sites. For the incident trains at both sites, wheel wear was evaluated as ranging from negligible to moderate and in both cases was within allowable limits. Rail head wear was similarly described as being well within allowable limits, with rails exhibiting some plastic flow and minor wear in the gauge corner region. However, the rail cant8 throughout both sidings was found to vary considerably and in some cases was close to zero. The assessment confirmed that some sections of rail may have been previously used elsewhere. The independent assessment of the wheel-rail interface found that, in most cases, contact occurred towards the gauge corner of the rails; this tendency being more evident for those rails with less-than-normal levels of cant (that is to say, a more-horizontal rail head).

8 Rail inclination to the vertical.

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1.5.3 Rail head surface condition

Two samples of rail head residue were taken from separate locations towards the terminating end of the siding. They showed the dominant material to be rust, with minor components of sulphur-based organic material and inorganic silicates or clay dust. Visual inspection following the incident indicated a growth of grass and weeds to a varying degree between the rails along much of the length of the siding; however, this growth did not generally project across or lie over the rail head and did not exist at all towards the end-of-track – the critical portion of the siding. The investigation did not consider this growth to be a threat to wheel-rail adhesion. There was no clear evidence on the rail head of lock-up wheelslide9.

Figure 4 – Intermittent vegetation at Pakenham train stabling track 5

9 In the context of wheelslide, a ‘loss of adhesion’ does not necessarily mean to the extent that wheels are not rotating

at all (are locked) while the vehicle continues to move. A ‘partial’ loss of adhesion may exist by which the wheel is rotating but not at the same speed as the vehicle is moving. This degree of wheelslide will not present the same degree of visible evidence on the rail head as would a fully-locked wheel. In fact, in some instances it may present no visible evidence at all.

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Figure 5 – Minimal vegetation near the end of the track

1.6 Environment

The weather for the 24 hours (0900 9 March – 0900 10 March) covering the incident period, as measured at the Bureau of Meteorology weather station closest to Pakenham (Cranbourne Botanical gardens, approximately 20 km SW), recorded total cloud cover and 8.8 mm of rain. An MTM report stated: “It was reported that the rails were wet at the time of the incident.”

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2. SANDRINGHAM INCIDENT

2.1 Circumstances

At about 2014 on 9 March 2011, train № X177 running the 1948 ‘empty cars’ service from Flinders Street Station arrived at the Sandringham Home Arrival signal SHM906. Shortly thereafter, the driver of the train received a Low Speed indication and moved across the Abbott Street level crossing and directly into the yard to stable in track 2. All tracks at Sandringham are dead-ended.

Figure 6 – Sandringham track layout

Proceeding straight ahead into track 2, the train failed to stop, overrunning the end-of-track by almost 14 metres, striking an overhead wire stanchion and then the wall of a commercial building. All wheels of the train’s leading bogie were derailed and a portion of the building structure demolished. The train’s windscreen was destroyed and parts of the leading-end fibreglass fairing sustained significant damage.

Figure 7 – Extent of damage to bank building

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Figure 8 – Exterior damage to bank building

The portion of the corner of the building—a retail trading bank—that was demolished included an area occupied by a customer service desk; this being the workstation of two bank staff members who would normally be sitting there during business hours.

Figure 9 – Internal damage to building and proximate staff workstation

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2.2 Train driver

The driver of train № X177 was considered fit for duty, and current in the required operating competencies. The driver reported that during the journey from the city to Sandringham the train’s performance under braking was to his expectation and that he was detained at the Sandringham Home Arrival signal for a brief period. After receiving a Low Speed indication on this signal he moved directly ahead into track 2. He stated that he applied the brakes prior to entering the [Abbott Street] level crossing but the train did not brake as expected. He then applied full service braking but again the brakes did not respond. He placed the controller into Emergency braking position and again the brakes did not apply. The driver reported that at this stage the train was picking up speed as it was a falling gradient at Sandringham and he was two thirds into road number 2 when he pressed the Park Brake button, but the end of the road was approaching quickly. He stated that the train then struck the baulks at the end of the road and proceeded through the [ballast] screenings which were heaped behind the baulks. The train then ran into the building and he was showered with glass from the windscreen shattering.

2.3 The train

The six-car train consisted of Siemens car-sets 822M-2561T-821M and 829M-2565T-830M. The train was not fitted with sanding devices to assist braking in low adhesion conditions (see section 3.1). Post-incident inspection did not identify any defect relevant to the incident.

2.4 Sequence of events

After stopping at the Down Home Arrival signal SHM906, the train received the requisite Low Speed indication (maximum speed 15 km/h) and proceeded directly into track 2. From signal SHM906 to the end of track 2, the distance is approximately 385 metres. From analysis of the train’s data recorder, the following sequence is apparent:

1. The train reached a speed of 36 km/h about 85 metres after moving away from signal SHM906. Over the next 180 metres a series of brake applications ranging between brake controller positions 1, 2, and 3 were made that slowly reduced the speed of the train. There were no indications of loss of adhesion or of the occurrence of wheelslide during this time.

2. The final braking sequence, initially at brake controller position 1, commenced a little over 100 metres from the baulks with speed at 26 km/h. At about the point at which braking was increased to position 2 (about 83 metres from the baulks), there was a recorded loss of wheel-rail adhesion on three of the four DM cars, and braking was reduced to brake controller position 1; the braking system remained in ED.

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3. After travelling a further 10 to 15 metres (now about 70 metres from the baulks), braking was again increased to position 2, and at this point, with speed now 23 km/h, a loss of adhesion was recorded on all DM cars and the braking system transitioned from ED to EP. The brake application was then rapidly increased until it was at the full service value about 55 metres before the baulks. An emergency brake application was made about 20 metres prior to the baulks and about 35 metres before the train came to a stand.

4. Once wheel-rail adhesion had been lost for the second time (about 70 metres from the baulks), the event recorder presented evidence of ongoing relative longitudinal creep (partial wheelslide), suggesting continued low levels of adhesion.

5. For the final stages of deceleration prior to the train coming to a stand, with braking first at Full Service and then Emergency, the calculated average deceleration was about 0.2 m/s².

Significantly, the rate of speed retardation indicated during this attempt to slow the train as it approached the end of the siding was somewhat less than that obtained earlier when the train was bought to a stand on the main line for the Down Home Arrival signal. At the end of the siding the train struck and overrode the timber baulks secured across the rails and continued for approximately a further 14 metres through ballast, striking a glancing blow to an overhead contact wire stanchion located slightly to the right of the train’s path before impacting the bank building. Although the lead DM car was derailed, and its lead bogie ran through ballast and could not therefore provide accurate evidence of distance after leaving the rails, an analysis of distance is afforded by cross-referencing the data from other DM cars in the train.

Figure 10 - Aerial image showing path taken and distance covered by derailed train

14 m

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2.5 Infrastructure

2.5.1 Track construction and geometry

The track geometry category that defines the structure of track 2 in the Sandringham station yard is siding track. It consisted of second-hand jointed rail dog-spiked to timber sleepers, and was in average condition. It was specified for a maximum speed of 15 km/h. Track geometry measurements for the final 157 metres of the siding were made post-incident by MTM and supplied to the investigation. All aspects of the track geometry were found to be within specified tolerances. Timber baulks were provided as the end-of-track protection.

Figure 11 – Timber baulks pushed together and overridden by the train

2.5.2 Rail head geometry

Refer to the independent assessment of wheel-rail interface at Pakenham and Sandringham in section 1.5.2.

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2.5.3 Rail head surface condition

Following the incident the friction properties of the rail head were independently analysed. Two samples of rail head residue obtained at separate locations near the terminating end of the siding showed the dominant material to be rust, with minor components of sulphur-based organic material and inorganic silicates or clay dust. Visual inspection following the incident indicated the growth of grass and weeds between the rails towards the end of the siding and evidence of some wheel-crush of vegetation matter on both rails at this location. Investigators, however, did not consider this to be either recent or of a significant degree. There was no clear evidence of locked wheelslide.

Figure 12 – Vegetation at Sandringham track 2

2.6 Environment

The weather for the 24 hours (0900 9 March – 0900 10 March) covering the incident period, as measured at the closest Bureau of Meteorology weather station (Moorabbin Airport, approximately 8.5 km ESE), showed total cloud cover and 5.2 mm of rain. An MTM report noted that it had been raining and that the track was wet.

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3. RESEARCH PERTAINING TO BOTH INCIDENTS

3.1 Siemens Electric Multiple Unit

3.1.1 History of braking performance

Since its introduction into service on the Melbourne metropolitan rail network in 2003, Siemens Electric Multiple Units (EMU) have been involved in a relatively high number of reported overrun events. Following further overrun events in 2009, a detailed investigation was undertaken by the Chief Investigator, Transport Safety. The investigation (Rail Safety Investigation Report No 2009/05) concluded that there was no identifiable defect on Siemens trains but as an integrated system the Siemens train was more prone to overrun than other types of train running on the network. Those features of the train identified as most likely to have contributed to overrun events related to the train’s influence on the wheel-rail interface and the response of the braking system during a wheelslide event. A further conclusion was that the majority of overrun events occurred in the presence of rail head moisture from light rain or dew and that this moisture, when combined in particular proportion with rail head contaminants such as iron oxides and mineral clay, could produce rail head conditions conducive to the development of reduced levels of adhesion at the wheel-rail interface. The investigation also acknowledged that contact conditions and the level of adhesion between wheel and rail could be influenced by the track geometry and rail head profile. The investigation examined a number of other factors contributing to overrun in specific instances including train handling, track grade and network risk management. The investigation reported that MTM commenced trials on a sanding device in March 2010, the purpose being to enhance wheel-rail adhesion during a wheelslide event. MTM reported that trials demonstrated significantly improved braking performance in conditions simulating reduced-adhesion conditions. MTM subsequently completed the installation of the sanding devices on all Siemens trains on 18 June 2011.

3.1.2 Specified braking deceleration

On dry, level track, the Siemens EMU has a specified deceleration of 0.9 m/s2 under full-service braking and 1.3 m/s2 when in emergency. Both rates have been shown to be met in dry conditions, in testing and in service.

3.2 End-of-track protection

3.2.1 Baulks

A ‘baulk’ is a length of sawn timber—most often a railway sleeper—usually applied across the rails in sets of two and designed to impede the movement of rail vehicles along a rail track. Historically, baulks have been applied at the discretion of Victorian railway District Engineers at the ends of sidings where freight wagons were stabled.

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3.2.2 Buffer stops

A buffer stop is a structure provided at dead-end platform tracks at mainline terminals and other dead-end sidings and designed to arrest the movement of rail vehicles at the end of these tracks. Buffer stops are currently specified in VRIOG Standards (see section 3.2.3) for reasons of asset protection and safety at the termination of single-ended siding tracks used to stow passenger rolling stock. In Victoria, buffer stops—as distinct from baulks—were traditionally required at the dead-end of sidings that were frequently used, and/or on a grade falling towards the dead-end10. For any collision above relatively minimal speeds, buffer stops were not intended to stop the moving rolling stock absolutely, but were designed to yield structurally under impact forces to an expected measure and thus serve to halt the movement by offering a robust obstruction to it while, at the same time, avoiding undue damage. Contemporary styles of buffer stops are designed to absorb considerably greater impact forces than has historically been the case while remaining structurally intact; although, depending on their design, this might result in greater damage to the derailed rolling stock and potentially greater harm to any occupants. Various friction types11 are available and are designed to absorb energy by sliding along the rail when impacted, providing a controlled deceleration of the train. Buffer stops currently in use in Victoria include UHMWPE-types12 derived from designs for wharf fenders, permanent structures of heavy steel construction fixed in concrete and friction types.

Figure 13 - UHMWPE buffer stops used at Melbourne's Southern Cross Station

10 Per Victorian Railways engineering policy (for example, see Way & Works Branch Plan № 239B, adopted Nov 1943). 11 These types of buffer stop are designed to absorb impact energy by sliding along the rails against a preset value of

friction, set by the application of a clamping force. Their design concept requires the existence of usable track length beyond their installed location.

12 Ultra-High Molecular Weight Polyethylene cone-type fenders designed for maritime application.

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Figure 14 - Steel buffer stops installed at Sandringham after the overrun incident

The investigation received information from other state railway authorities regarding their processes for the management of trains entering dead-end tracks, and for managing the risk of overrunning. Public Transport Authority of Western Australia Transperth have adopted the use of friction or hydraulic buffers where practicable; friction buffers being their preference. This operator’s application of ATP13 requires that passenger trains entering dead-end tracks are restricted to a maximum speed of 10 km/h.

Figure 15 – A friction-type buffer stop used in Western Australia

13 Automatic Train Protection - A railway electronic technology designed to ensure safe operation in the event of human

failure.

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Rail Corporation New South Wales Railcorp specifies the design requirements for buffer stops that apply to all terminal roads and sidings where passenger trains operate by application of a Civil Engineering Standard14. This standard specifies, among other things:

- approved materials – including that, except for fixed buffer stops, timber shall not be used and that masonry cannot be used at all

- that energy-absorbing buffer stops are preferred where passenger trains operate

- that ‘lower-order protection devices’ (stop-blocks and earth or ballast run-off areas) may be used where passenger trains do not operate. Stop blocks may be timber bearers or concrete sleepers

- that a risk assessment shall be made at each location to determine the design performance criteria and whether additional overrun protection is required.

Figure 16 – A friction-type buffer stop used in New South Wales

3.2.3 Victorian Rail Industry Operators Group Standards

VRIOG Standards are a collaborative product of this group, whose membership comprises rail operators (including MTM) and the Public Transport Division of the Department of Transport. The standards are intended to facilitate the interoperability of infrastructure across the state. Their use is not prescribed by law. The VRIOG Standards for train stabling facilities15 states that it shall be applied in any circumstance of substantial alteration to, or new construction of, train stabling. The standard states that each site will have its own constraints and requirements and that the minimum consideration for usage of the standard will be agreed by the Director of Public Transport and the relevant Accredited Rail Operator (ARO). The standard did not exist when the current layouts of the Pakenham and Sandringham railyards were created.

14 ESC 361, v2.3 Feb 2011. 15 VRIOGS 004.13 Rev A 26/10/10, Train Stabling Facilities.

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For the termination of a stabling siding, the VRIOG Standards states that buffer stops shall be provided at the termination of each single-ended siding track for asset protection and safety. It specifies that the design requirements for buffer stops will be site specific and determined by factors such as operational requirements and factors influencing speed and force of impact. It also specifies that a risk assessment of each location shall be conducted by the ARO in conjunction with the Director of Public Transport. The standard states that baulks may be used as stand-alone or in conjunction with a buffer stop, subject to approval by the ARO.

3.3 Regulatory regime

In Victoria the provision of safe rail operations is sought through the Rail Safety Act 2006 (Vic). The Act describes a number of principles of rail safety, including:

Principle of shared responsibility. A shared responsibility for rail safety of the rail operators, rail safety workers, the Director, Transport Safety16, other persons who are involved in the design, construction and maintenance of rail infrastructure and rolling stock operations, and the public.

Principle of accountability for managing safety risks. Managing risks associated with rail infrastructure or rolling stock operations is the responsibility of the person best able to control that risk (that is to say, the operator).

Principle of enforcement. The enforcement of the Act and regulations should be undertaken for the purpose of public safety, promoting improvement in rail safety, removing incentive for any unfair commercial advantage that might be derived from contravening the rail safety requirements under the Act or Regulations, and influencing the attitude and behaviour of those persons whose actions may have adverse impacts on rail safety.

Rail operators are required to be accredited by the Director, Transport Safety. (Some exemptions are allowed for in the Act, particularly associated with private sidings). To obtain accreditation a rail operator is required to have a safety management system (SMS) that complies with the Act and regulations. The SMS must be in place, maintained, and complied with by the rail operator in respect to the rail operations the operator carries out while accredited. Rail operators applying for accreditation are required to demonstrate to the Director, Transport Safety that they have the competency and capacity to manage risks associated with the rail operations for which accreditation is sought. To manage risks, a rail operator is required to identify all incidents that could occur while carrying out operations and identify all hazards that cause, or contribute to causing, those incidents. The Act requires that a rail infrastructure manager must, so far as is reasonably practicable, ensure the safety of rail operations carried out by them. In doing so they are required to eliminate risks to safety, so far as is reasonably practicable and if it is not reasonably practicable to eliminate risks to safety then reduce those risks so far as is reasonably practicable.

16 A position created under the Transport Integration Act 2010 whose primary object is to independently seek the

highest safety standards that are reasonably practicable.

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The rail safety regulators role The Director, Transport Safety is the Victorian rail safety regulator. Transport Safety Victoria (TSV) acts as a support agency in assisting the Director in carrying out this role. The role of the regulator is to provide independent oversight of the management of safety by rail operators and all those with safety duties under the Act. This is achieved through safety audits and compliance inspections. The program of audits and compliance inspections is based upon safety intelligence using risk assessments, incident information and data and alerts from railway employees and passengers. TSV use enforcement tools to achieve compliance with the law taking into account the ‘so far as is reasonable practicable’ legal test.

3.4 MTM risk management

As an ARO, MTM is required to maintain a safety management system that provides, among other things, for hazard identification and risk management in accordance with their statutory obligations. The provision of adequate infrastructure and accessories (for example, baulks and buffer stops) is part of these obligations. The investigation has been advised by MTM that in assuming the Melbourne metropolitan rail franchise from Connex Melbourne Limited (CML), they inherited three separate operational risk registers: one from CML itself; one from MainCo, their infrastructure maintenance provider; and a third from United Group Melbourne Transport Ltd, their rolling stock maintenance provider. Towards the end of 2010, MTM launched their own SMS and have been working to consolidate the CML and MainCo risk registers, a process that has included a rationalisation of the Risk Matrices. Following a recent spate of end-of-track overruns17, MTM completed a review of hazard identification relevant to dead-end sidings. This has resulted in a streamlined Risk Assessment/Review of Train to Train Running Line Collision document, and generated a prioritised list for attention. MTM have also reviewed their application of the ‘so far as is reasonably practicable’ (SFAIRP) test.

17 Carrum Siding on 3 March 2011, Pakenham and Sandringham Sidings on 9 March 2011 and Macleod Railway

Station on 24 March 2011.

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4. ANALYSIS

4.1 The incidents

The two incidents occurred almost within an hour of each other. Although the locations were dissimilar, the circumstances were not. Both incidents involved Siemens trains being moved into stabling sidings at speeds exceeding that permitted and in wet conditions. The outcomes were also similar, with both trains overriding timber baulks and colliding with significant infrastructure.

4.2 Train operation

Both drivers operated their trains at speeds in excess of the authorised speed of 15 km/hr permitted for siding operations. In the Pakenham incident, the train entered the stabling siding at a speed almost three times that permitted, and in the Sandringham incident in excess of twice that permitted. As the trains approached within 70 metres of the end-of-track baulks, both were still in excess of the speed permitted, travelling at about 20 km/h at Pakenham and 23 km/h at Sandringham. The trains were also not operated in a manner that would have been prudent given they were running on wet siding track. This was especially the case given the well-known history of inconsistent braking performance of Siemens trains in such conditions.

4.3 Train braking performance

In both incidents, train deceleration was lower than expected by the driver and during the final braking sequence, considerably less than dry braking deceleration. Consistent with the identified wheelslide and in the absence of any identified train defect, the investigation has concluded that the lower than expected deceleration was the result of low levels of adhesion at the wheel-rail interface. Previous investigation by the Chief Investigator identified that the Siemens EMU was prone to the development of low wheel-rail adhesion in particular conditions. In both these instances it is probable that low adhesion conditions were developed as a result of the trains’ interaction with siding track having less than ideal rail head geometry and in the presence of moisture. It is likely that this moisture mixed with normally occurring rail head contamination, such as iron oxides and clay, to form a layer conducive to the development of low levels of wheel-rail adhesion. In these incidents, vegetation is not considered to have been contributory to the existence of these conditions.

4.4 End of track protection

In both incidents, the end-of-track protection was baulks consisting of two sleepers lying across the track and fixed to it. In both cases the train ran over the top of the baulks before colliding with infrastructure. Clearly, the baulks provided no defence against a train overrunning them and as such the only purpose they could be considered as serving was as an indication to drivers of the position of the end of the track.

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4.5 Risk management

The traditional requirements for protecting dead-end siding tracks against overrun by passenger rolling stock were more stringent than is permitted in the contemporary era. The risk in both of these locations of track overrun at a speed greater than that able to be controlled by baulks could reasonably have been identified as an inherent hazard, and a current VRIOG Standards addresses this. A stanchion supporting the overhead electrified catenary existed within a proximate distance to the end-of-track at one of the locations, and a commercial building was similarly located at the other; neither being hazards that can be overstated. The location of these structures might have been expected to have raised some level of disquiet during the hazard identification process of the previous and current network managers. Such concern would have justified specific consideration (especially considering the previous incidents of overruns at end-of-track and station platforms and the brake problems associated with Siemens trains) of the possible outcomes should one or some of the considered risk mitigations fail to protect against a track overrun. Also, it could be argued that the regulator might have been more proactive in their audits of both the risk registers maintained by Connex and MTM for this particular risk. As a result of these incidents, MTM have reviewed their decisions around risk attached to possible overrun at stabling sidings. Buffers have been provided at tracks 1 and 2 at Sandringham and the catenary stanchion at the end of siding track 5 at Pakenham has been relocated clear of the overrun zone for this track.

4.6 Application of VRIOG Standards

VRIOG Standards did not exist when the yard layouts at Pakenham and Sandringham were created and VRIOG Standards did not require that they be applied retrospectively. Nonetheless, it would be prudent in the pursuit of a continuous improvement in rail safety, for any rail operator who is a member of the Victorian Rail Industry Operators Group to consider the retrospective application of these guidelines. Such consideration in these two instances may have resulted in the application of an increased level of overrun protection. In considering the possible benefit to rail safety of the existence of VRIOG Standards, the question of their purpose might be examined. While it would be onerous to require the standards to be applied retrospectively, AROs should be required to demonstrate to the regulator at audit that they have considered the implications of new or revised VRIOG Standards in their safety management systems.

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5. CONCLUSIONS

5.1 Findings

In both instances:

1. The driver of the train was qualified and assessed as medically fit for duty.

2. The train transited the siding at speeds significantly in excess of that permitted.

3. The siding track was fit-for-purpose.

4. The dead-end sidings were not equipped to prevent a train overrun at anything other than the slowest speed.

5.2 Contributing factors

In both instances:

1. The train was operated at an excessive speed for the prevailing track and environmental conditions.

2. The braking performance of the train was less than expected by the driver.

3. As a result of the train’s interaction with the wet siding track, low adhesion conditions were developed at the wheel-rail interface.

4. An effective means to arrest overrunning rolling stock at the end-of-track was not provided.

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6. SAFETY ACTIONS

6.1 Safety Actions taken since the event

Since these incidents, MTM have completed a risk review of all stabling sidings. The investigation was advised that this has produced a prioritised list of sidings with the highest likely consequence in the event of a train overrun and that the report generated from this review will inform future infrastructure works. Infrastructure changes have been made at both incident locations. At Pakenham siding track 5, the catenary support structure that was struck by the derailed train has been relocated clear of the overrun zone. At Sandringham siding tracks 1 and 2, steel buffer stops have been installed (see Figure 14 in section 3.2.2). MTM also advised that they have issued alerts to train drivers regarding their obligation to adhere to posted speeds. Since these events, MTM have completed the installation of sanding equipment to all Siemens trains including those involved in the incidents (see section 3.1).

6.2 Recommended Safety Actions

Issue 1

In both of these incidents the trains were operated contrary to the operating rules and procedures. While the operator has a driver audit program, this program was not effective in ensuring compliance in these two incidents.

RSA 2012012

That Metro Trains Melbourne reviews the processes available to them to improve the monitoring of and adherence to rules for the operation of trains.

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