Loading, Degradation and Repair of F-111 Bonded Honeycomb Sandwich Panels - Preliminary Study

摘要

Many of the fixed and removable panels on the RAAF F-111 aircraft are made up of bonded honeycomb sandwich panels. Experience with the RAAF fleet has shown that a serious problem exists with degradation and damage of these panels. A review of the literature was undertaken to gain an understanding of the extent of this problem. It was found that panels were subject to large areas of adhesive bond separation and corrosion damage. This damage was believed to be caused by the ingress of water in the panel through poor sealing at the edges or after repair of the panels. Moisture in the panel is also believed to cause adhesive degradation that may reduce the strength of the bonds in such panels. At the same time the literature was surveyed to determine the design load cases for such panels. This information was used to develop a simple finite element model of a bonded honeycomb sandwich panel. This model was in turn used to generate data on the loading and failure of such panels. In addition, an understanding ofF-111 Structural Repair Manuals and the RAAF Engineering Standard C5033.