ballooning

bal·loon·ing /bəˈlu:nɪŋ/ noun

[noncount] : the activity or sport of riding in a hot air balloon
▪ She's always wanted to go ballooning.

— bal·loon·ist /bəˈlu:nɪst/ noun, plural bal·loon·ists [count]
▪ an experienced balloonist [=a person who goes ballooning]