摘要: Reducing the separations between aircraft can improve airport capacity and decrease delays. This report addresses the feasibility of reduced IFR separation standards on final approach, and identifies the characteristics of the ATC... 展开 Reducing the separations between aircraft can improve airport capacity and decrease delays. This report addresses the feasibility of reduced IFR separation standards on final approach, and identifies the characteristics of the ATC system which affect or are affected by the separation standards. This study has been limited to conditions during which wake turbulence is not a factor. Given this assumption, separation reduction will be most limited by the need to avoid simultaneous runway occupancy by successive arrivals. As the interval between landings decreases, so must the time spent on the runway, if dual runway occupancy is to be avoided. For acceptable performance, the average runway occupancy time must be no more than 50 seconds for a 2.5 nmi minimum separation standard or 37 seconds for a 2.0 nmi standard, with the current ATC system. Various technical improvements now under development may make it possible to operate a 2.0 nmi minimum with average runway occupancies as great as 45-50 seconds. Adequate communications and surveillance for the controller, and enforcement of current ATC procedures are also required for operations with reduced separations. An alternative solution to the runway occupancy problem is to use a pair of close-spaced, dependent (dual-lane) runways and alternate arrivals between them. Reduced separation on approach to a single runway cannot be realized until the wake vortex problem is resolved. 收起