Status Report on NASA Two-Segment Approach Program

NASA, in cooperation with the FAA, is evaluating the two-segment approach as a routine procedure for reducing aircraft noise. The program calls for separate flight evaluations using a 727 and a DC-8, and an extrapolation of these results to determine the adaptability of the technique to the rest of the fleet. After a review of the total program, this paper presents (i) the profile and procedures developed and the noise reduction achievable, (ii) the vortex characteristics behind an aircraft on a two-segment path, and (iii) cost estimates for retrofitting aircraft with two-segment avionics.