Her only Olympic appearance was in London in 1948 when she was a member of the last team to travel to an Olympic Games by ship. The sea trip took about 8 weeks and there was a significant loss in form due to the lack of training facilities on board ship. Galloway was the only woman in the team and the regulations of the day meant a chaperone was necessary to look after her. Mimi Ingram was her chaperone and had to pay her own way to the Olympic Games in London. Galloway did not know how to get around the city or where she could find a swimming pool suitable for training.
"The Great Britain team heard of my dilemma and invited me to join their training," Galloway recalled. "I trained with them and their coach helped me." Galloway competed in the 100m backstroke and became close friends with Helen Yates, who swam the same event for Great Britain. One of the highlights for Galloway was to beat Yates and win the English title in a lead-up event. "I felt guilty beating her because she had helped me a lot," Galloway said. "She became one of my best friends and we have kept in touch ever since."
In the Olympic 100m Backstroke, Ngaire was 7th in her semi-final and had the 11th fastest time.