Accession Number : ADA306884

Title :   A 4-Flap Design with Graphite and Boron Composites,

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

Personal Author(s) : Hawley, A. V. ; Ashizawa, M.

PDF Url : ADA306884

Report Date : OCT 1968

Pagination or Media Count : 12

Abstract : The design and development of an A-4 landing flap is described. The flap was initially selected as a suitable component for obtaining flight experience with boron filaments. The existing production aluminum flap was redesigned utilizing boron skins supported by a full depth honeycomb core, while retaining some of the basic component aluminum parts for interchangeability reasons. A second flap design, utilizing graphite as the composite reinforcement and developed in accordance with advanced structural element concepts such as molded graphite parts to replace aluminum rib and hinge fittings was developed. The choice of skin layup and core geometry is explained. It is shown to depend not only on the strength and stability of the skin but also on the temperature and pressure conditions that exist during the cure and secondary bonding. Emphasis is placed on the problems encountered during the design and development phases rather than on those which came to light during the final detailed analysis.

Descriptors :   *FLAPS(CONTROL SURFACES), *BORON, *GRAPHITE EPOXY COMPOSITES, LOAD DISTRIBUTION, TENSILE STRENGTH, STRESS ANALYSIS, ALUMINUM ALLOYS, STRUCTURAL PROPERTIES, LAMINATES, STIFFNESS, FIBER REINFORCED COMPOSITES, MODULUS OF ELASTICITY, MATRIX MATERIALS, THERMAL EXPANSION, AERODYNAMIC LOADING, COMPRESSIVE STRENGTH, SKIN(STRUCTURAL), AIRCRAFT LANDINGS, LANDING GEAR, CYCLIC LOADS, ADHESIVE BONDING, SANDWICH PANELS, HONEYCOMB CORES, SHEAR STRENGTH, STRESS CONCENTRATION.

Subject Categories : Laminates and Composite Materials
      Aircraft

Distribution Statement : APPROVED FOR PUBLIC RELEASE