The early diesel locomotives were big, heavy and under-powered compared to the steam locomotives they replaced. The 3300hp Deltic (above) was one of the early challengers with sufficient muscle for the task. But this power was dearly bought. A typical diesel-electric locomotive cost about five times as much as the equivalent steam locomotive, and machines like the Deltic were highly tuned, needing a well planned support operation with teams of skilled technicians to keep them going day in and day out. The days of muck shovelling by unskilled labour were over.
What was the early experience with diesels? It was claimed that they could keep running 22 hours a day, and the better designs probably could. The difficulty was, and is, that there is not the traffic to keep them occupied in this way, and once complete fleets had been acquired, expensive capital was inevitably kept idle for long periods. This is the economic reality of running a railway. Demand varies over the course of a day, a week, a year, and over the longer economic cycle. Railway equipment can spend long periods out of use over the course of its life of thirty or forty years.
This is why yield management needs to be applied to both short-term and long-term cycles. One solution is to keep a mix of new and old, using the efficient new stock all the time and bringing out the less efficient old fleet to cope with peak demands.
Inga kommentarer:
Skicka en kommentar