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The Atlas H was a stage and a half rocket, using the enhanced Atlas rocket designed for use as the first stage of the Atlas G rocket, which differed from the Atlas H in having a Centaur upper stage. This stage was later reused as the first stage of the Atlas I. In practice, an MSDupper stage was flown on all five launches.
This template lists historical, current, and future space rockets that at least once attempted (but not necessarily succeeded in) an orbital launch or that are planned to attempt such a launch in the future
Symbol indicates past or current rockets that attempted orbital launches but never succeeded (never did or has yet to perform a successful orbital launch)