Aigner made his debut at the
2021 World Para Snow Sports Championships where he won gold medals in the slalom, and parallel event, and silver medals in the super-g and giant slalom events. Aigner competed at the
2022 Winter Paralympics and won gold medals in the
downhill and
giant slalom. He also won silver medals in the
super combined and
slalom and a bronze medal in the
Super-G. He competed at the
2023 World Para Alpine Skiing Championships and won gold medals in the downhill and alpine combined, and silver medals in the Super- G and giant slalom events. He was subsequently awarded the Rising Star Award at the 2023 Para Sport Awards. He won the 2025–26 FIS Para Alpine Ski World Cup overall crystal globe for the fifth consecutive season. ==Personal life==