ABSTRACT
It follows that HSR can substitute for only a modest part of total air travel. It cannot compete on long flight distances and can only compete on shortto medium-flight distances when market conditions are favourable. But the relationships between HSR and air travel are not only substitutive, they can also be complementary. Four types of complementarity are possible:
v HSR can serve as a feeder to airports for medium-and long-distance flights; v HSR can provide short-to medium-distance travel services to city pairs in
which the airlines are not much interested; v HSR can be used as a backup system if air connections have to be cancelled
because of weather conditions or other problems; v HSR can be used as a feeder system for freight parcel service.
