Avio has a major share in the production of the solid rocket motor for Ariane 5, which carries 240 tons of solid propellant. The two boosters of Ariane 5 launcher deliver 90 percent of the thrust to the launcher at take-off for 130 seconds. Both separate from the central body of the launcher at a height of 60 km.
The booster has three segments: S1, S2 and S3, built separately and integrated by Avio in French Guiana, completed with the igniter and the nozzle.
The S1 segment
The S1 segment is one of three segments for the Ariane 5 booster and is fully manufactured in Avio’s
Colleferro plant (Rome, Italy), except for the metallic part manufactured by MT Aerospace.
The manufacturing process is:
• application of thermal protection
• loading with 25 tons of solid propellant
• inspections of forward and back chicanes – (in a series of inspections and checks to verify its compliance to the project)
The loaded segment is then shipped to French Guiana, where it is assembled to the S2 and S3
The S2 e S3 segments
The S2 and S3 segments (the metallic part is manufactured by MT Aerospace) once thermally protected (at the Colleferro), are then shipped to French Guiana where they are each loaded with 107 tons of propellant by the Regulus company (60% Avio and 40% Ariane Group). All the segments are then integrated by Europropulsion, a company equally shared by Avio and Ariane Group and assembled with the igniter and the nozzle by ASL.
The booster igniter is also manufactured in Colleferro plant. It has three stages: pyrotechnical igniter, intermediate and principal. The three stages are thermally protected, filled with propellant, and after being checked, they are shipped in French Guiana where they are assembled and integrated on the booster. Each igniter is filled with about 65 kg of propellant.