Mechanical pre-sizing of Ariane

This application developed over the years by the pre-dimensionning teams of Airbus Defense & Space aims at early definitions of the geometry of rockets. It has been used originally for Ariane 6, and will be maintained for the next generations.


The design of spatial launcher is a challenging field on both scientific and industrial front. In order to make the european launcher competitive, Airbus Defence & Space (formerly Astrium), decided to improve its preliminary project studies with more innovation in designs and technical solution. It will thus provide better results to client while reducing delays. 

Means to achieve better quality, increased innovation and reduced cost:

  • Improve ways to work together within Airbus DS
  • Improve knowledge and data management
  • Improve calculation tools:
    1. Improve the way information is exchanged between tools
    2. Improve the range of their capabilities
    3. Make them more generic



To do so, Airbus Defense & Space developped a software environment organised around 3 interconnected module 


# Architecture preconception tool

The main application of this tool is to create launcher architecture by assembling elements from a library. The existing code has been initially developed in-House.

# Load calculation tool

This tool enables to calculate static and dynamic loads during flight. This existed in Matlab and has been rewritten in Scilab.

# Pre-sizing tool

This tool uses the decomposition into elements (architecture preconception tool) to size them individually with loads (find geometry that holds the loads and minimises mass) and calculates consolidated mass of elements.

Sizing criterions : Resistance, Buckling, Stiffness

A preliminary first version of the pre-sizing tool has been developed in-house on Scilab but needed to be industrialised further. Scilab Enterprises helped to develop a more dynamic GUI and improve the code using vector calculation while the ADS team provide a more robust data structure.


This is how the Graphical User Interface of the application “Sizelab” looks like: