Topic summary
Two-stage
Extracted from the Wikipedia article Multistage rocket.
Two-stage-to-orbit
A two-stage-to-orbit (TSTO) or two-stage rocketlaunch vehicle is a spacecraft in which two distinct stages provide propulsion consecutively in order to achieve orbital velocity. It is intermediate between a three-stage-to-orbit launcher and a hypothetical single-stage-to-orbit (SSTO) launcher.