ZEFIRO-23 second stage
The Vega’s second and third stages both use Zefiro solid rocket motors. These stages, each 1.9 meters in diameter, comprise a filament-wound carbon-epoxy case, with low-density EPDM insulation and a nozzle with flex-joints, equipped with electromechanical actuators to direct the thrust.
The Zefiro 23 second stage is 8.39 meters long, and is loaded with 23,814 kg. of solid propellant HTPB 1912, providing maximum vacuum thrust of 1 120 kN. It operates for approximately 78 seconds.