"The Project aim is to develop and demonstrate an advanced structural surface cooler mounted in an appropriate core fairing composite structure. Currently surface coolers are an integral feature of advanced turbofan engine designs. They contribute to achieving the best engine performance by maintaining oil and fuel temperatures within defined limits and by virtue of their mounting on the inside of the fancase they obviate the need for additional ducting of air and a control valve to switch the air on/off. The lack of ducting and control valve leads to an overall cost and weight reduction. Oil and/or fuel is cooled by the passage of cool engine bypass air flow over the air washed surface of the heat exchanger.Current surface coolers are parasitic to the existing engine structure, and occupy surfaces that can also be used for acoustic treatment to control engine noise. As such the weight, volume and efficiency of the surface cooler are all of great importance.The design and installation of a compact and lightweight structural surface cooler in a core fairing structure will contribute positively to the efficiency of the power-plant by providing the necessary oil cooling at minimum overall weight and hence optimal fuel burn..Also it is envisaged that surface cooler/composite core fairing designs will evolve that employ novel structural design, advance manufacturing techniques, potentially novel materials and new concepts in utilising air washed surfaces on the engine. The structural integration of the metallic structural surface cooler to a composite core fairing type structure has been identified as an important area for success. The joint must allow a strong load path, handle dissimilar degrees of thermal displacement and provide sealing yet being light and durable. Therefore mounting of such a surface cooler in a composite core fairing structure will also be researched for future engines where composite air washed structures may be used"