Vernier Thruster Implementations
One type of vernier thruster is a smaller rocket engine used for attitude control in conjunction with a larger spacecraft propulsion engine. Due to their weight and the extra plumbing required for their operation, vernier rockets are seldom used for new designs. However, R-7 rocket family, with over nineteen hundred successful launches to date, is based on Vernier rocket design solution.
The Space Shuttle's reaction control system had six vernier engines or thrusters. During STS-130 commander Zamka and pilot Terry Virts used the space shuttle Endeavour's vernier thrusters to reboost the International Space Station to its correct altitude.
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