The research task will be to develop optimal parameters of welding lap joints with use of friction stir spot welding FSSW (RFSSW) process to weld fuselage thin skins (<2 mm) and aircraft skins with stringers. The optimization of the FSSW (RFSSW) parameters will be based on the selection of adequate parameters for the skin thickness, such as tool rotational speed, tool insertion time, mixing time, time of tool returning, etc. An important part of the work will be research on the choice of suitable adhesive bond for effective RFSSW lap joints. The adhesive layer should fill the gaps of a joint, protecting the inner surfaces from corrosion. Please refer to the full topic descriptions document published in this call.