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Abstract.The adhesive fracture energy, G c , is determined from two types of elastic-plastic peel tests (i.e. the single-arm 90 o and T-peel methods) and a linear-elastic fracture-mechanics (LEFM) test method (i.e. the tapered double-cantilever beam, TDCB method). A rubbertoughened epoxy adhesive, with both aluminium-alloy and steel substrates, has been used in the present work to manufacture the bonded joints. The peel tests are then modelled using numerical methods. The overall approach to modelling the elastic-plastic peel tests is to Further, it has been found that the calculated values of G c are independent of whether a standard LEFM test or an elastic-plastic peel test method is employed. Therefore, it has been demonstrated that the value of the adhesive fracture energy, G c , is independent of the geometric parameters studied and the value of G c is indeed a characteristic of the joint, in this

The upwards trend for the use of electrical power on state of the art aircraft is resulting in significant change to the design of power system architectures and protection systems for these platforms. There is a pull from the aerospace industry to integrate the electrical power system with the aircraft's structural materials to form an embedded system, reducing the need for bulky cable harnesses. This directly impacts the fault response for ground faults and ultimately the development of appropriate protection systems. Such structural materials include composites such as carbon fibre reinforced polymer (CFRP). This paper presents the experimental capture and analysis of the response of CFRP to electrical fault current, which indicates the need for two distinct sets of electrical ground fault detection criteria for low and high resistance faults and identifies the threshold resistance for this distinction. By extrapolating these results to develop models of CFRP for use in transient simulation studies, the key electrical fault detection thresholds for speed, selectivity and sensitivity for a DC system rail to ground fault through CFRP are identified. This provides the first set of key factors for electrical fault detection through CFRP, providing a platform for the design of fully integrated structural and electrical power systems, with appropriate electrical protection systems.Index Terms-Carbon fibre reinforced polymer, electrical protection, more-electric aircraft.Electrical and thermal effects of fault currents in aircraft electrical power systems with composite aero-structures.S