Abstract: An exhaust nozzle bell for a rocket engine including a first part arranged on a motor of the rocket engine, and a second part coupled to the first part. The second part having a stowed position in which the second part surrounds the first part and is positioned closer to the motor, and an operating position in which the first part and the second part form a continuous shape and the second part is arranged farther from the motor. Moreover, the nozzle can include an extension mechanism structured and arranged to extend the second part from the stowed position to the operating position, the extension mechanism including a plurality of swiveling extension arms, wherein the extension arms have first and second ends. Furthermore, each of the extension arms comprise one of a sliding and rolling element on an end facing the second part of the exhaust nozzle bell.