To win back shares in the freight traffic market lost to road-based competitors, the project ETNA (development of technologies for improving the product) will be launched by SNCF as an experiment starting in 1988. Using a computer-based system, freight trains will be made up as unit trains for three classes of service, i. e. very urgent, urgent and less urgent freight, and thus be fully utilized. The trains will run at speeds between 100 and 160 km/h. The number of slower trains will be reduced. Owing to the high operating speeds, the cars will have to be modified at the bogies or replaced with new designs.