Cowan rail crash
Encyclopedia
The Cowan rail accident occurred at 7:20pm on 6 May 1990 when the 3801 Limited
3801 Limited
3801 Limited is a not for profit company limited by guarantee. It was incorporated on 5 June 1985; A.C.N. 002 951 671. The registered office of the company is at Australian Technology Park.- Establishment :...

 special steam
Steam locomotive
A steam locomotive is a railway locomotive that produces its power through a steam engine. These locomotives are fueled by burning some combustible material, usually coal, wood or oil, to produce steam in a boiler, which drives the steam engine...

 passenger train returning from the Morpeth Jazz Festival was struck in the rear by the following CityRail
CityRail
CityRail is an operating brand of RailCorp, a corporation owned by the state government of New South Wales, Australia. It is responsible for providing commuter rail services, and some coach services, in and around Sydney, Newcastle and Wollongong, the three largest cities of New South Wales. It is...

 inter-urban passenger service. The steam train had stalled while attempting to climb the steep gradient
Gradient
In vector calculus, the gradient of a scalar field is a vector field that points in the direction of the greatest rate of increase of the scalar field, and whose magnitude is the greatest rate of change....

 from the Hawkesbury River
Hawkesbury River
The Hawkesbury River, also known as Deerubbun, is one of the major rivers of the coastal region of New South Wales, Australia. The Hawkesbury River and its tributaries virtually encircle the metropolitan region of Sydney.-Geography:-Course:...

 to Cowan, New South Wales
Cowan, New South Wales
Cowan is a suburb of northern Sydney, in the state of New South Wales, Australia. Cowan is located 40 kilometres north of the Sydney central business district, in the local government area of Hornsby Shire and is part of the North Shore region. Cowan shares the postcode of 2081 with Berowra...

, and it was found that sand applied to the rails to regain traction had interfered with the signals
Railway signal
A signal is a mechanical or electrical device erected beside a railway line to pass information relating to the state of the line ahead to train/engine drivers. The driver interprets the signal's indication and acts accordingly...

 and given the following train a false clear indication
Wrong-side failure
A wrong side failure describes a failure condition in a piece of railway signalling equipment that results in an unsafe state.A typical example would be a signal showing a 'proceed' aspect when it should be showing a 'stop' or 'danger' aspect, resulting in a "false clear"...

.

Overview

The crash occurred approximately 5 kilometres (3.1 mi) south of Brooklyn, New South Wales
Brooklyn, New South Wales
Brooklyn is a small suburb of northern Sydney, in the state of New South Wales, Australia. Brooklyn is located 51 kilometres north of the Sydney central business district, in the local government area of Hornsby Shire and is part of the North Shore region...

, near the Boronia No. 3 tunnel
Tunnel
A tunnel is an underground passageway, completely enclosed except for openings for egress, commonly at each end.A tunnel may be for foot or vehicular road traffic, for rail traffic, or for a canal. Some tunnels are aqueducts to supply water for consumption or for hydroelectric stations or are sewers...

. The railway line at this point, known as the Cowan Bank
Cowan Bank
-Overview:The Cowan Bank is a 8.6 km double-track section of standard gauge railway line between Cowan railway station 48.8 km north of Sydney, New South Wales, Australia and Hawkesbury River railway station 57.4 km north of Sydney...

, is 2.5% (1 in 40) grade and, as the special hauled by C38-class steam locomotive
Steam locomotive
A steam locomotive is a railway locomotive that produces its power through a steam engine. These locomotives are fueled by burning some combustible material, usually coal, wood or oil, to produce steam in a boiler, which drives the steam engine...

 3801 passed southwards through the No. 3 tunnel, the wheels of the locomotive started to slip
Slip (vehicle dynamics)
In vehicle dynamics, slip is the relative motion between a tire and the road surface it is moving on. This slip can be generated either by the tire's rotational speed being greater or less than the free-rolling speed , or by the tire's plane of rotation being at an angle to its direction of...

. The driver of 3801 applied sand
Sandbox (railways)
A sandbox is a container on most locomotives and self propelled multiple units, or trams, that run on tramways and adhesion railways...

 to the rails to improve traction
Traction (engineering)
Traction refers to the maximum frictional force that can be produced between surfaces without slipping.The units of traction are those of force, or if expressed as a coefficient of traction a ratio.-Traction:...

, but the train came to a complete stop approximately 50m clear of the tunnel. Passengers on the steam train reported seeing a signal fluctuating aspects
Railway signal
A signal is a mechanical or electrical device erected beside a railway line to pass information relating to the state of the line ahead to train/engine drivers. The driver interprets the signal's indication and acts accordingly...

 between green and yellow. The following CityRail V set inter-urban train, which had been halted at the northern entrance to Boronia No. 4 tunnel for 10 minutes by a red stop signal
Railway signal
A signal is a mechanical or electrical device erected beside a railway line to pass information relating to the state of the line ahead to train/engine drivers. The driver interprets the signal's indication and acts accordingly...

, received a green indication and proceeded, colliding with the steam train shortly after.

The impact killed the driver of the inter-urban, Gordon Hill, and a passenger who was riding in the inter-urban's cab, as well as four passengers in the rear carriage of 3801's train. 99 passengers were injured, 11 of those seriously. The force of the crash completely destroyed the last carriage of the steam train, and was enough to break the locomotive coupling and push the engine 12 meters forward.

A coronial inquiry
Coroner's Court of New South Wales
The name of "Coroners Court" is the generic name given to proceedings in which a Coroner holds an inquest or an inquiry in New South Wales. Coroners have jurisdiction over the remains of a person and the power to make findings in respect of the cause of death of a person...

 heard by Mr Derrick Hand subsequently found in December 1990 that the sand that had been applied to the rails by 3801 to aid traction had insulated the train from the rails and had caused the track circuits to fail to detect the presence of the train in the block, allowing the following inter-urban train to be given a false green clear aspect (known as a Wrong-side failure
Wrong-side failure
A wrong side failure describes a failure condition in a piece of railway signalling equipment that results in an unsafe state.A typical example would be a signal showing a 'proceed' aspect when it should be showing a 'stop' or 'danger' aspect, resulting in a "false clear"...

). Mr Hand also considered it likely that a passenger on 3801 had applied a handbrake on the third carriage, and that this, combined with the heavy load, steep grade and curvature of the line had prevented the steam train from restarting. No fault was found with the signalling system, although the coroner recommended that it be upgraded as soon as possible.

Contributing factors

Contributing factors include:
  • AC
    Alternating current
    In alternating current the movement of electric charge periodically reverses direction. In direct current , the flow of electric charge is only in one direction....

     track circuit
    Track circuit
    A track circuit is a simple electrical device used to detect the absence of a train on rail tracks, used to inform signallers and control relevant signals.- Principles and operation :...

    s, which are less sensitive at detecting rail vehicles.
  • No indication of track circuit state to the controlling signal box
    Signal box
    On a rail transport system, signalling control is the process by which control is exercised over train movements by way of railway signals and block systems to ensure that trains operate safely, over the correct route and to the proper timetable...

    , which might have alerted the signalman
    Signalman (rail)
    A signalman or signaller is an employee of a railway transport network who operates the points and signals from a signal box in order to control the movement of trains.- History :...

     of a possible shunting
    Shunt (electrical)
    In electronics, a shunt is a device which allows electric current to pass around another point in the circuit. The term is also widely used in photovoltaics to describe an unwanted short circuit between the front and back surface contacts of a solar cell, usually caused by wafer damage.-Defective...

     problem caused by sanding.
  • The signalling system was two-aspect colour light - a three aspect colour light may have provided the driver of the following train with more warning.
  • No sand removal system fitted to 3801.
  • No mechanism (at the time) for train-to-train or train-to-signalman communication (communication with signal boxes was only possible by track-side phones).
  • It is believed that the handbrake
    HandBrake
    HandBrake is a general-purpose, open-source, cross-platform, multithreaded video transcoder software application. HandBrake was originally developed by titer in 2003 as a general-purpose video transcoder to make ripping a film from a DVD to a data storage device easier...

    s on one of the carriages may have been applied as a stunt

Consequences

  • An interim ban was placed on the use of steam locomotives on the NSW railway system. The ban was lifted 9 months later.
  • Operators were required to use one State Rail employee on each train
  • Operators were required to carry insurance cover of $10 million. The government agreed to underwrite any claims exceeding that amount.
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