Bidirectional?
It means a single line which allows trains to run in both directions.
There are obvious dangers with bidirectional lines, the most serious of which is the possibility of two trains on the same line in opposite directions – it has happened in the past.
The simplest method of controlling such a line is to have only one train operational, on the basis a single train cannot collide with itself. Such a system is known as “one-train working."
The main disadvantage is single line running restricts the number of train movements which can be made.
Bidirectional or single line tracks are the predominant system in most of Australia with double line running only in metropolitan areas, on major routes such as Sydney to Newcastle or on coal lines where there is continuous running.
My early education
My dad, a train driver then, was able to answer all my questions regarding the single line running so when I became involved many years later, it was easier to learn.
Reliance is placed not on employing only one train in the single line section but on having a single physical object available for the single-track section and ruling a driver may enter the single line section only if in physical possession of the object.
That object is known as a ‘staff’ and is marked to indicate to which single track section it belongs.
Physically seeing the staff provided assurance there could be no head-on collision.
Inconvenient?
Using only a single token (the staff) does not provide convenient operation when consecutive trains are to be worked in the same direction. The simple token system was therefore extended.
So how do we ensure the only trains on a single line are running in the same direction?
If one train was to be followed by another in the same direction, the driver of the first train was required to be shown the token (staff), but not take possession of it (in theory he was supposed to physically touch the token, but this was not strictly followed).
The driver was given a written authority to enter the single line section, referred to as the ‘ticket.’ They could then proceed, and a second train could follow.
In the earliest days, the second train could proceed after a designated time interval. However, following the Armagh rail disaster of 1889, block working (safeworking) became mandatory.
To ensure the ticket is not issued incorrectly, a book of numbered tickets is kept in a locked box, the key to which is permanently fastened to the token or is the token.
Staff and Ticket
In addition, the lock prevents the token being removed until the ticket box is closed and it cannot be closed unless the book of tickets is in the box. Once a ticket is issued, its number is recorded in a Train Register book, and the token is locked in a secure place.
This system is known as staff and ticket.
In a variation on this principle, called divisible train staff, a section of the token referred to as the ticket portion was designed to be removed and handed to the driver instead of a paper ticket.
Along the single line, what the railwaymen called ‘loops’ but better known as sidings, to allow for one train to pass another in either direction, controlled by signals similar in most respects to traffic lights.
An example of this would be a fast passenger train passing a slower moving goods (or freight) train.
Often, these sidings were yards where goods trucks (freight wagons) could be shunted off for delivery to customers
Modern technology
I remember when the milk train from the North Coast of NSW, carrying milk obviously, and destined for Sydney, was given free passage to pass other trains along the way – milk, after all, is perishable.
The staff and ticket system worked successfully in Australia for many years and led to rail being described as the safest way to travel. I believe flying now holds the title but I’m not sure.
Modern technology is gradually taking over from those manual jobs and the staff and ticket system is being phased out but it worked very well for over 100 years in Australia and if necessary, could be reinstated with nothing more than a re-education program for drivers and guards alike.
We humans aren’t trains but there is a similarity. We’ve been asked to travel on the narrow road which leads to eternity, not the broad way which leads to eternal damnation but we don’t need a ticket or a staff.
The Apostle Paul says, “if you confess with your mouth Jesus as Lord and believe in your heart that God raised Him from the dead, you shall be saved.” (Romans 10:9)