H-I

The H–I or H–1 was a Japanese liquid-fuelled carrier rocket, consisting of a license-built version of the Thor-ELT, which was originally constructed for the US Delta 1000 rocket, and all-Japanese upper stages. The H in the name represented the use of liquid hydrogen fuel in the second stage. It replaced the N-II, and was subsequently replaced by the H–2, which used the same upper stages with a Japanese first stage.