Resources

2016 – Sept- Erdos – Collision involving road-train truck and train 8834N near Narromine, New South Wales, 23 September 2015

Author(s):

Date presented: January 4th, 2017

Safety summary – what happenedOn 23 Sep 2015, a road-train truck collided with train 8834N at the Tullamore - Narromine Rd railway crossing, NSW. The railway crossing was controlled by flashing lights, bell, approach warning signs & road markings. The collision/post-impact fire destroyed the truck. The truck driver was fatally injured. The train sustained minor damage, the second wagon derailed. One set of flashing lights destroyed.

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2016 – Sept – Cox – Level Crossings, When is enough, enough?

Author(s):

Date presented: January 4th, 2017

Introduction Level crossings represent high risk exposure for railway operators. Obligation for engineers and railway operators is to ensure level crossing risks are seen to be reduced So Far As Is Reasonably Practicable (SFAIRP). Grade separation is best solution but how can we ‘sweat’ level crossing assets? Once you have ‘lights, booms and gongs’ what then? Road complexity, number of cars, type of traffic, frequency of trains all increase risk What else can we do?

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2016 – July – Pfister – Swiss Army Knife vs KISS How to optimise a level crossing

Author(s): Mathius Pfister

Date presented: July 24th, 2016

Assuming you get the job to implement or update a new level crossing: You will be confronted with lots of stakeholders,influencers and legislative guidelines. The national regulator is giving you a certain framework. Investors, be it therailway operator or the infrastructure owner usually limit your ambitions in terms of money. There is only a limited budgetavailable and it needs to be spent wisely. In contrast, other stakeholders such as end users or neighbours, living next toa crossing, usually tell you exactly how things should work - or more often - how they shouldn’t.This document addresses general areas of conflict. Furthermore, it shows how national regulator, infrastructure owner oroperator can influence the value for money proposition to achieve improved cost structures or whole of life costs as wellwhat suppliers can do in order to ensure lower cost and safe level crossings. The paper highlights cost savings due tobetter selected requirements and provides a simple example.

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2016 – July – Macdougall – Headway as Part of the Operating Plan

Author(s): Terry Macdougall

Date presented: July 24th, 2016

Signal engineers and train operations staff often misunderstand each other when talking about headway. When someone in the operations team refers to headway, they actually mean the interval between trains expressed in minutes. They assume that the interval between trains is enough to deliver a reliable on-time service. Signal engineers however calculate headway as the absolute minimum time between following trains that will allow drivers to retain line speed without having to apply brakes due to passing yellow signals. The signal design will generally try to space signals so that there is a fairly uniform headway across a section of line. The worst headway on the line sets the "ruling headway" for the line. This is sometimes called the theoretical signalling headway. Trains travelling closer than the ruling headway will meet at least one yellow signal and be forced to apply brakes, and will therefore lose time. This in turn will delay the following train and so on, causing cascading and compounding delays. Several factors contribute to achieving reliable train frequencies, such as the permitted line speed, driver behaviour, train acceleration & braking rates, train length, signalling principles (such as overlap length), planned station dwell time, and most importantly, passenger behaviour. This paper provides a brief background on classical headway theory; some insight on how track speed and station dwell time impact on achievable capacity; a case study to demonstrate that terminal stations may pose a greater constraint on capacity than the signalling; and a suggested method to allow quick assessment of achievable capacity on a new line.

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2016 – July – Heibel – CBTC Versus ETCS – Score and Forecast

Author(s): Dr Frank Heibel FIRSE

Date presented: July 24th, 2016

Modern in-cab signalling can increase capacity beyond the limits of conventional legacy systems and also improve service punctuality. The present market for in-cab signalling is divided in two segments. For mainline railways on a national level, the European Train Control System (ETCS) is preferred by railway operators well beyond the reach of European legislation. For high performance metro-style city railways, Communications Based Train Control (CBTC) is the solution of choice. Both technologies have different purposes and histories and consequentially developed distinct strengths but also weaknesses. The suburban railway systems in the major Australian cities appear in a transition from a mainline legacy to high capacity metro ambitions. The technology selection between ETCS and CBTC is therefore less straightforward with no clear "right" or "wrong" and examples for either system evolving in Australia. However, operators need to recognise and accept the consequences of selecting either technology. The paper concludes with an outlook on further development of both technologies, which concentrates on addressing the individual shortcomings while maintaining existing advantages. The evolving subject of "convergence" between ETCS and CBTC will be discussed to assess whether there will be only one "best" signalling technology in the future.

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2016 – July – Green – Re-Engineering Level Crossing Safety

Author(s): Terry Green FIEAust CPEng

Date presented: July 24th, 2016

This paper describes components and processes to re-engineering level crossing safety by controlling the movement over level crossings for both road and rail vehicles. This is primarily aimed at highway crossings and in particular remotely located crossings on heavy haulage rail lines. The rail corridor has always been designated as a permanent way with the train driver as the only stopping control to avoid collisions with obstructions. With the introduction of new technologies and driverless train projects the need to detect obstructions and control the passage of trains across conflict zones such as level crossings has become vital. These new technologies must be introduced with strict operational guidelines that are fit for purpose. Technology that increases train delays due to false or unreliable alarms is not an acceptable solution. System components for this design will include  Duplicated Flashing Lights  Duplicated Half Boom Gates  Barrier protection around level crossing equipment locations  CCTV with integrated crossing state logging  Obstruction Detection in the crossing zone  Duplicated Advance Warning Lights  Road Speed Reduction  Rumble Strips  Full Road Pavement Markings and duplicated road signage  Vital Communications to stop the train All components play an important role in level crossing protection.

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2016 – July – Burns – Time Based Movement Authorities

Author(s): Peter Burns

Date presented: July 24th, 2016

Modern communications based signalling places improved signalling functionality on board the train. This can be used to enforce conventional temporary speed restrictions using location based authorities. With these the train ensures its speed is maintained below the temporary maximum between two defined points. In a related class are time based authorities. A time based authority commences at a specified time and continue to a specified event (which is not necessarily time based). Two examples are presented. The first relates to a requirement to restrict passing speeds within a long tunnel to below a specified maximum (as is the case for the Seikan tunnel in northern Japan). In this case the signalling system is aware of the location and authorized speed of the two passing trains in advance. With this knowledge a passing point can be predicted in terms of location. However, a speed restriction based on this criterion can be shown to be unsound as a provider of safety. Thus a safety benefit is obtained by defining the passing point in terms of time; a time based authority emerges. The second relates to level crossing protection. It is conventional in a class of signalling to require a train to obtain an authority to cross a protected level crossing. Communications base signalling allows a train to communicate its arrival time to the level crossing as part of the process for obtaining that authority. This is another class of time based authority – the train obtains authority to cross at a specified time. Once communicated, the train is able to regulate its progress safely to ensure it does not arrive prior to the specified time. The crossing is able to ensure that the standard warning is provided prior to the authorised arrival time. The paper explores the characteristics of, and requirements for time based authorities.

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2012 – July – P Hughes – You cant get good train control

Author(s):

Date presented: May 23rd, 2016

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1993 – April – Mitchell – BHPs Mt Newman Rail Signals Group Involvement

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Date presented: May 23rd, 2016

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2005 – Oct – Braban and Yelloz – Resignalling and Interoperability

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Date presented: May 23rd, 2016

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