Liquid rocket boosters

A liquid rocket booster (LRB) consists of liquid fuel and oxidiser as booster to give a Liquid-propellant rocket or a hybrid rocket an extra boost at take off. It is attached to the side of a rocket. In contrast to solid rocket booster it can be throttled.

A liquid rocket booster (LRB) uses liquid fuel and oxidiser to give a liquid-propellant or hybrid rocket an extra boost at take-off, and/or increase the total payload that can be carried. It is attached to the side of a rocket. Unlike solid rocket boosters, LRBs can be throttled down, and can be shut down safely in an emergency for additional escape options in human spaceflight.

By 1926, US scientist Robert Goddard had constructed and successfully tested the first rocket using liquid fuel at Auburn, Massachusetts.

For the Cold War era R-7 Semyorka missile, which later evolved into the Soyuz rocket, this concept was chosen because it allowed all of its many rocket engines to be ignited and checked for function while on the launch pad.

The Soviet Energia rocket of the 1980s used four Zenit liquid fueled boosters to loft both the Shuttle Buran and the experimental Polyus space battlestation in two separate launches.

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