Accession Number : ADA301579

Title :   Boron/Aluminum Skins for the DC-10 AFT Pylon.

Descriptive Note : Final rept.,

Corporate Author : MCDONNELL DOUGLAS CORP LONG BEACH CA DOUGLAS AIRCRAFT DIV

Personal Author(s) : Elliott, S. Y.

PDF Url : ADA301579

Report Date : MAY 1975

Pagination or Media Count : 151

Abstract : Four boron/aluminum aft pylon "boat tail" skins are designed and fabricated and three of them are installed on three DC-lO aircraft for a 5-year flight service demonstration test. The fourth skin is retained as a spare and all skins will be replaced at the end of the service period by their titanium counterparts. Inspection and tests of the exposed skins will establish the ability of the boron/aluminum composite to withstand long time flight service conditions, which include exposures to high temperatures, sonic fatigue, and flutter. The results of a preliminary testing program yield room temperature and elevated temperature data on the tension, compression, in-plane shear, interlaminar shear, bolt bearing, and tension fatigue properties of the oriented 11 ply boron/aluminum laminates and this information together with a stress analysis are used to obtain FAA approval. Present state-of-the-art technology (emphasizing low cost) was used in the fabrication of the skins and these are installed on the existing titanIum substructure with the same number of the same sized mechanical fasteners as are used for the present titanium skins. The boron/aluminum skins measure approximately 20.32 x 170.18cm (8 x 67 inches) and are 2.032mm (0.080 inch) thick. Although maximum weight saving was not sought, the 1.56Kg (3.45 lb) weight of the constant thickness boron/aluminum skin is 26% less than the chemically milled titanium skin.

Descriptors :   *METAL MATRIX COMPOSITES, *ALUMINUM, *BORON, MEASUREMENT, TEMPERATURE, COMMERCIAL AIRCRAFT, STRESS ANALYSIS, EXPOSURE(GENERAL), LOW COSTS, STATE OF THE ART, COMPOSITE MATERIALS, HIGH TEMPERATURE, LAMINATES, STRUCTURES, FABRICATION, TENSION, FATIGUE(MECHANICS), TITANIUM, FASTENINGS, SKIN(STRUCTURAL), WEIGHT REDUCTION, FLUTTER, SPARE PARTS, SONIC FATIGUE, BOLTS, MECHANICAL COMPONENTS.

Subject Categories : Commercial and General Aviation
      Laminates and Composite Materials

Distribution Statement : APPROVED FOR PUBLIC RELEASE