Aluminium alloys 2024 and 7175 are vital in the aerospace and automotive industries due to their high strength and low weight. Understanding their behaviour under dynamic loading is essential for safety and reliability. There is limited detailed analysis of these alloys fractography under dynamic shear compression, making it hard to predict failures. This study examines the fractography of 2024 and 7175 aluminium alloys under dynamic shear compression using a compressed air launched projectile. The fracture surfaces were analysed with scanning electron microscope (SEM) and optical microscope to observe microstructural changes and adiabatic shear band (ASB) formation. Results show the formation of adiabatic shear bands in AA 7175, offering key insights into their dynamic failure mechanisms. These findings enhance our understanding of aluminium alloys under high strain rates, aiding in the design of more durable aerospace and automotive components.