Development and Application of Separation Analysis Methodology for Noise Abatement Approach Procedures

Abstract

Noise abatement approach procedures have proven to be a cost effective means of achieving near-and medium-term noise and emissions reductions. However, routine application of these procedures is yet to occur. The major roadblocks are the uncertainties in future trajectory of aircraft, the difficulty such uncertainties presents for air traffic controllers having to predict and control separations, and the consequent impact on airport capacity. This paper describes a research targeting to help the air traffic controller predict and manage separations between aircraft performing noise abatement procedures so that these procedures can be implemented at more airports to benefit the communities and operators as well as to ease the constraint on traffic growth. The research first developed a fast-time flight simulator, and modeled factors driving flight trajectory variations. Those driving factors include stochastic aircraft landing weight, pilot response delay, and wind variations between flights. Specifically, a unique wind variation model based on non-linear mode decomposition was developed. Aircraft meteorological reports were used as data source for modeling the wind. The flight simulator together with the models of trajectory variation driving factors formed a Monte Carlo simulation tool. A noise abatement approach procedure framework was proposed. The research then developed a separation analysis methodology to utilize the developed Monte Carlo simulation tool to predict desired initial separation at an intermediate metering point between aircraft performing noise abatement procedures. The initial separation was to be used by air traffic control to assure safe separation would not be violated in the execution of noise abatement procedures. The separation analysis methodology was designed such that the determined initial separation maximizes capacity without sacrificing safety and noise abatement benefits. The Monte Carlo simulation tool and the separation analysis methodology were then applied to a continuous decent flight demonstration test at Louisville International Airport using UPS Boeing 757 and Boeing 767 revenue flights. The flight demonstration test and the follow on analysis of radar data showed close match between simulation results and observed separation between aircraft and thus proved the effectiveness of the tool and analysis methodology.