The concept envisages very large - possibly nuclear-powered - aircraft flying on stable circuitous routes that connect major centres of population. These large cruisers remain airborne for very long periods so that they could be considered to be permanently cycling around their designated route.
They would fly at an economical altitude and speed which would not vary substantially.Linking these cruisers to fixed bases near the population centres would be short range shuttle aircraft designed only to travel from the ground to the an interception with the cruiser and back again.
Courtesy of ACARE