Carbon fibre-reinforced polymer (CFRP) is a crucial material in aerospace parts. A key engineering challenge is wrinkles in composite structures during manufacturing, which have a dramatic effect on structural strength. Multi-scale imaging on industrial parts (≥1 metre) is conducted to understand the micro-scale mechanisms (< 100 µm) that lead to the formation and evolution of macro-scale wrinkles. This new in situ experiment uses an industrially applied technique of hot diaphragm forming of thick multi-layer carbon fibre (CF) flat stacks with semi-cured polymer into part shapes. The multi-scale deformation mechanisms are characterised, and the wrinkles metrics are quantified to understand the defect formation and evolution. These beamline experiments are essential in understanding microscale wrinkle mechanics, leading to a positive and direct impact on composite design and manufacture of ultra-light, emission aerostructures.