Zefiro-23

Avio Zefiro-23 is the filament-wound composite-casing HTPB solid rocket motor used on the second stage of the original Vega launcher. Avio's product page publishes 24 t propellant, 1,122 kN mean thrust, 287.5 s specific impulse, and 77 s ignition duration; ESA identifies the motor as Vega's second-stage solid motor and gives a 71.6 s combustion reference. The row remains retired with the original Vega vehicle, while the manufacturer evidence now preserves the distinct motor architecture and rating context.