Guest post by Dr Geoff Hudson
Everyone likes high speed trains. The Shinkansen (aka “Trunk Route”) trains in Japan are famous. Smooth, speedy, punctual. The problem is the track costs a fortune – $30,000,000 per kilometre is typical. Mag-Lev (Magnetic Levitation) and Hyperloop (Evacuated tube) systems are even more expensive. The problem for high speed rail is that the rails must be in exactly the right position, and must stay in that position from day to day. This is often referred to as good or perfect track alignment. If the tracks move, the train is bumped and possibly derailed. Laying tracks on sleepers on gravel (aka ballast) on the ground means that freight trains can jiggle the tracks around and changes in the moisture content of the ground below the ballast can move the track. Replacing the sleepers and ballast with immovable concrete is the major part of the cost of high speed rail.
Of course the rails and sleepers are not all you need. Signalling systems to avoid train collisions must be included and can cost around $2,000,000 per kilometre. High speed trains in Europe and Japan have overhead electric power at another $2,000,000 per kilometre, and similar costs can be spent removing level crossings.
There have been dozens of studies into high speed rail in Australia. They have all adopted the view the European and Japanese trains are the only available technologies. All have been rejected mainly because of the high cost of laying the rail. There have even been studies showing that the long rail line lengths and low population in Australia condemn high speed rail here. It is just not economic.
Our politicians say that innovation is what we need to supply employment and economic growth. We badly need high speed trains, but seem to make no attempt to create a technology which escapes the basic rolling stock design of the last century. The major innovation which is relevant to the use of existing rail tracks for high speed transport in the last 100 years is the tilting mechanism created by the British Advanced Passenger Train (aka APT) about 50 years ago and then sold to Italian train developers. A Swedish tilt train was tried by NSW a couple of decades ago, but failed because the train alignment was inadequate.
The only escape from this financial trap that I can see is to develop a new train which can run at high speed on our existing tracks. It might have to slow down for bends and stations, tunnels and passing other trains, but if it could do 250 km/hr, you could commute from many regional towns. Why is no-one studying this? It is a peculiarly Australian need, yet we persist with the basic bogie design of the last 100 years. We still use sloped wheels to allow the outer wheel to cover more ground than the inner wheel on a turn, even though that fails with flange squealing so often. We still bolt the carriage down to the bogie with the all the restraint needed at a station, for the entire journey. It is as if there is a religion that says that only the Europeans and Japanese can develop high speed trains and we must not change the basic suspension of trains. The rails that must remain as they are, not the rolling stock.
I have done some sums and I am convinced that a new vehicle can be designed to travel safely and comfortably at 250 km/hr on many parts of our existing rail network. The longest straight stretch of rail in the world (478 km), on the Nullarbor plains is only one of the appropriate targets. Will anyone help me build this vehicle?
A documented and more detailed technical account can be downloaded here.