The cylindrical drum structure of the duct was designed in light alloy and the bell-mouth entry and downstream diffuser sections were molded from fiberglass. The problems of making such sections accurately were considerable, and hardwood plugs representing a third of the circumference were first made as the formers for the heavy fiberglass molds. To minimize dangers arising from propeller blade tip contact with the duct, the whole of the inner section of the structural box is covered with a layer of polyurethane foam faired into the leading and trailing edge moldings. The main purpose of this ducted propeller project is to secure a substantial reduction in noise.

Media Info

  • Pagination: p. 317-323

Subject/Index Terms

Filing Info

  • Accession Number: 00135847
  • Record Type: Publication
  • Source Agency: Engineering Index
  • Files: TRIS
  • Created Date: Jul 13 1976 12:00AM