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In page Buran programme:

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  • Energia's four boosters used liquid propellant (kerosene/oxygen). The Space Shuttle's two boosters used solid propellant.[3]
  • The liquid fueled booster rockets were not constructed in segments vulnerable to leakage through O-rings, which caused the destruction of Challenger.[citation needed]
  • Energia's four boosters were designed to be recovered after each flight,[4] though they were not recovered during Energia's two operational flights. The Space Shuttle's boosters were recovered and reused.