Research on Separation and Emission Reduction of Regional Airliner Based on Wake Encounter Response Model

Abstract

To ensure the safety of aircraft operation, the current regional passenger aircraft maintains a large distance from the preceding aircraft in actual operation, which result in reducing the operation efficiency of airports and airspace, and increasing pollutant emissions. To address these issues, in this paper, two aircraft types are selected in which the CRJ-900 encounters the trailing wake vortices of the A380 in front. An improved strip model is developed to build the CRJ-900 overall response wake encounter value. First, the safety of the CRJ-900 longitudinal and lateral wake encounters in different flight stages is analyzed. Second, we calculate the critical safety separation and its impact on air transport efficiency. Third, we use the LTO model to measure the reduction of aircraft fuel consumption and pollutant emissions. The results demonstrated that the medium-sized aircraft CRJ-900 has the potential to reduce the wake separation when following the super-heavy A380 aircraft. In terms of the critical safety separation calculated by the safety index, the operating efficiency of airports and airspace could be effectively improved, allowing the reduction of pollutant emissions during aircraft take-off and landing. During the takeoff, level flight, and landing phase, the results are summarized as follows: when the CRJ-900 is 13km away from the A380, the maximum lift variation is 11334N, 8157N, and 7366N; the maximum rolling moment variation is 43836N•M, 35274 N•M, and 28487 N•M; the maximum value of the rolling moment coefficient (RMC) is 0.0171, 0.0160, and 0.0130; when the RMC critical value is 0.031, the maximum safe separation for different flight stages is 11960m, which is 1040m shorter than the existing separation; when the RMC critical value is 0.05, the maximum safe separation distance of each stage is 10083m, a reduction of 2917m compared with the existing separation; when the RMC threshold is 0.07, the maximum safe separation of different flight stages is 9021m, a reduction of 3979m compared to the existing separation; when the RMC value is between 0.031-0.07, the fuel consumption can be reduced by 7.9%–12.8%, and the pollutant emission can be reduced by 9.1%–12.8%.