Accession Number : AD0729443

Title :   Approaches to Evaluating the Effects of VFR Towers on Flow and Safety at Airports,

Corporate Author : NATIONAL BUREAU OF STANDARDS WASHINGTON D C

Personal Author(s) : Joel,L. S. ; Steele,W. A. ; Filliben,J. J. ; Hare,G. B.

Report Date : APR 1971

Pagination or Media Count : 195

Abstract : The Federal Aviation Administration is reviewing its criteria (now based on annual traffic levels) for airports to be eligible for the installation of VFR towers. In support of that review, a study was commissioned to seek mathematical methods and models for measuring the effects of a VFR tower on flow and safety at airports with different traffic volumes. The report discusses a variety of methodologies, viewpoints, and concepts. The first version of a mathematical model, intended to portray a tower's ability to expedite flow by abridging the full operation sequence, was formulated and exercised in illustrative calculations. Available aggregated data are not adequate for identifying functional relations between collision rates and activity levels at tower and non-tower airports; however a novel statistical approach has established the association between tower-presence and lower collision rates on a firmer basis than before. More knowledge is needed concerning pilots' information needs, relative to potential hazards, which go unmet in the absence of a VFR tower; as an initial contribution along this line, a computerized model was developed to air in studying the pilot's time-varying field of vision as limited by cockpit geometry and other structural obstructions. (Author)

Descriptors :   (*AIR TRAFFIC CONTROL SYSTEMS, AIRPORTS), (*AIRPORTS, *AVIATION SAFETY), AIR TRAFFIC, MATHEMATICAL MODELS, STATISTICAL ANALYSIS, AVIATION ACCIDENTS, VISIBILITY

Subject Categories : Terminal Flight Facilities

Distribution Statement : APPROVED FOR PUBLIC RELEASE