Space X, Amazon and Boeing are currently engaged in a great battle to conquer space. Recently, Boeing CEO Dennis Muilenburg said that Boeing will be sending the first humans to Mars, not SpaceX.

These companies are developing reusable launch systems which are capable of launching a payload into space more than once. No completely reusable orbital launch system has ever been created; however, several partially reusable launch systems have existed.

Boeing and Lockheed Martin have formed a joint venture, United Launch Alliance, to develop a reusable rocket.

A recent patent granted to Boeing discloses a unique multi-stage space launch system which includes two stages and a thrust augmentation stage. The thrust augmentation stage includes a bore that engages with the first stage. The thrust augmentation stage and the first stage both provide thrust during the initial portion of a launch, and the first stage continues to provide thrust during the launch trajectory following the thrust augmentation stage.

Further, the thrust augmentation stage is configured to be selectively decouple from the first stage during the launch trajectory. Thereafter, the thrust augmentation stage descends in a controlled manner to land vertically on Earth. It is subsequently retrieved and reused for another launch.

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