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Bourquin, K. R.

Publications and source records attributed to Bourquin, K. R..

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 (1) the profile and procedures developed and the noise reduction achievable, (2) the vortex characteristics behind an aircraft on a two-segment path, and (3) cost estimates for retrofitting aircraft with two-segment avionics.

Denery, D. G.

Description and flight performance of two systems for two-segment approach

This paper describes two different avionic systems which were designed and developed to provide guidance and control for two-segment noise abatement approaches. The concept of a low-cost retrofit avionic system evolved into a special-purpose two-segment computer which required a DME collocated with the ILS glide-slope transmitter. This system was evaluated in a Boeing 727-200 aircraft. The second system is an area navigation (RNAV) system modified to include the two-segment approach. This system is more sophisticated than the first system and does not restrict usage to any specific navigation ground aid. The modified RNAV system is a Collins ANS-70A and is currently being evaluated in a DC-8-61 aircraft.

Wehrend, W. R.

Jet transport noise - A comparison of predicted and measured noise for ILS and two-segment approaches

Centerline noise measured during standard ILS and two-segment approaches in DC-8-61 aircraft were compared with noise predicted for these procedures using an existing noise prediction technique. Measured data is considered to be in good agreement with predicted data. Ninety EPNdB sideline locations were calculated from flight data obtained during two-segment approaches and were compared with predicted 90 EPNdB contours that were computed using three different models for excess ground attenuation and a contour with no correction for ground attenuation. The contour not corrected for ground attenuation was in better agreement with the measured data.

White, K. C.

Flight evaluation of three-dimensional area navigation for jet transport noise abatement.

The NASA, working with American Airlines, has completed the first phase of research to evaluate the operational feasibility of two-segment approaches for noise abatement. For these tests, area navigation was used to establish the upper glide slope and an ILS was used to establish the lower. The flight director was modified to provide command information during the entire approach. Twenty-eight pilots representing the airlines, professional pilot associations, FAA, and NASA participated. With an ILS approach for comparison, the procedure gave a noise reduction of 18 EPNdB at the outer marker and 8 EPNdB 1.1 n. mi. from touchdown.

Denery, D. G.