LONGER FREIGHT TRAINS: POSSIBILITIES AND LIMITATIONS

Long heavy freight trains are in regular scheduled operation in Russia, the USA, Canada, Brazil, South Africa, and Australia. The heaviest trains so far have had a gross load of 40,000t, and trains with 24,000t loads are not uncommon. Many trains are over 3km long. These railways usually separate freight and passenger traffic as far as possible, and use only bogie wagons to carry freight. The advantages of longer heavier trains include: (1) greater throughput and thus greater capacity on congested lines; (2) no need to build double tracks or passing tracks; and (3) savings in numbers of locomotives and locomotive drivers. This paper presents an investigation by Swiss Railways (CFF/SBB) of the possibility of placing longer freight trains in service on the north-south main line via the Gotthard Tunnel under the Alps. The reasons for the study were related to threatened congestion on part of the rail network and the need to find more cost-effective freight transport. Aspects considered included journey times, traction, power supply and overhead lines, and signalling installations. The tests conducted showed that freight trains up to 1.5km long would be feasible if their individual wagons had relatively uniform braking properties; it would be necessary to use locomotives remotely controlled by radio.