This project is devoted to the pre-development of Alphabus Central Tube (@CT), equipment which belongs to the structure subsystem of the Alphabus spacecraft. This pre-development consists in demonstrating through theoretical studies and samples manufacturing that the next spacecraft generation could benefit from new technological or industrial improvements, i.e.:
The issues can be divided in design and manufacturing issues:
Main design issues
Main manufacturing issues
The @ CT belongs to the @BUS primary structure which will provide a performance gap over than +50% compared to the current SPACEBUS 4000 or EUROSTAR 3000 primary structures.
The @BUS platform is expected to support up to 8.5 tons spacecraft launch mass. With regard to the Central Tube, this pre-development will enable improvements and industrialization of existing baseline (Mecabus Central Tube heritage) Several design improvements and manufacturing process evolution will issue an overall enhancement of the performances of the central tube (quality of the product and health of the composite materials).
The global shape of the tube is cylindrical. On its lower part, a ring called "launcher junction frame" (LJF) provides the fitting between the cylinder and the launcher adapter. An intermediate ring called "intermediate frame", on the outside of the @CT provides a base for several I/F. On the upper side, the @CT is connected with the first floor through the First Floor Frame (FFF) .
The interface with launcher is the standard ACU 1666mm as described in ARIANE 5 User's Manual.
According to pre-development results, this baseline could be improved/modified accordingly.
The expected project plan is built in 3 steps as follows:
Phase 1 of this pre-development has been completed with the Technology Evaluation Review held beginning of 2005.
The main results of the Phase 1 studies are: