Optimizing the flow of aircraft through a new work of bases requires some modification of the standard network flow algorithms because of the special nature of air transportation. The pay load carried by an airplane is a function of the distance between refueling stops, as well as field conditions at the bases; and in general the maximum allowable payload is not the same on all arcs of the network. Thus the shortest route through a network is not necessarily the route of maximum payload flow per hour of flight time, a trivial example being a plane which can fly non-stop from origin to destination but only with zero payload. Two air network problems analogous to the shortest path and the maximum flow problems are considered. These are the route of maximum payload flow per hour of flight time and the maximum steady-state payload flow through a network with base capacity constraints. (Author).