# ASTERION FCTA-1 — Version 0.8 Release Notes

Version 0.8 converts the Version 0.5 findings into a controlled redesign. The selected H3 design is not the lightest candidate and not the stiffest candidate; it was selected because it satisfies every provisional Version 0.8 criterion with lower mass than the heavier H4 and H8 alternatives.

## Main changes

1. **Central spine:** radius increased from 1.2 m to 1.8 m while retaining 160 × 6 mm longerons.
2. **Frames and diagonals:** increased to 130 × 5 mm and 100 × 4 mm respectively.
3. **Ring torque path:** 48 cross-spokes create triangulated torque paths between the outer rings and inner support structure.
4. **Docking:** eight long load spreaders transfer docking moments to station X=14 m.
5. **Propulsion:** twelve longitudinal struts convert the thruster load path from local bending to predominantly axial action.
6. **Braking model:** simultaneous braking now applies opposite torques to counter-rotating rings. A separate single-ring fault case is retained.

## Selected results

- Idealised structural mass: **10423.4 kg**
- Dry docked mass: **53223.4 kg**
- Misaligned docking: **22.870 mm**
- Propulsion thrust: **0.215 mm**
- Balanced braking: **1.846 mm**
- Single-ring fault braking: **3.487 mm**
- First supported mode: **0.1964 Hz**

These remain screening results from an ideal-joint Euler–Bernoulli frame model. Authoritative ANSYS results are still required.
