Five business jet airplanes were flown to determine the noise reductions that result from the use of modified approach procedures. The airplanes tested were a Gulfstream 2, JetStar, Hawker Siddeley 125-400, Sabreliner-60 and LearJet-24. Noise measurements were made 3, 5, and 7 nautical miles from the touchdown point. In addition to a standard 3 deg glide slope approach, a 4 deg glide slope approach, a 3 deg glide slope approach in a low-drag configuration, and a two-segment approach were flown. It was found that the 4 deg approach was about 4 EPNdB quieter than the standard 3 deg approach. Noise reductions for the low-drag 3 deg approach varied widely among the airplanes tested, with an average of 8.5 EPNdB on a fleet-weighted basis. The two-segment approach resulted in noise reductions of 7 to 8 EPNdB at 3 and 5 nautical miles from touchdown, but only 3 EPNdB at 7 nautical miles from touchdown when the airplanes were still in level flight prior to glide slope intercept. Pilot ratings showed progressively increasing workload for the 4 deg, low-drag 3 deg, and two-segment approaches. (Author)

  • Corporate Authors:

    Edwards Flight Research Center

    National Aeronautics and Space Administration
    Edwards, CA  United States  93523
  • Authors:
    • Burcham, FWJ
    • Putnam, T W
    • Lasagna, P L
    • Parish, O O
  • Publication Date: 1975-11

Media Info

  • Pagination: 31 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00146733
  • Record Type: Publication
  • Source Agency: National Technical Information Service
  • Report/Paper Numbers: NASA-TM-X-56037
  • Files: TRIS
  • Created Date: Feb 16 1977 12:00AM