DECISION SA - Construction et réalisation de structures en matériaux composites

Now that we have completed the “Rivages” project of building Bernard Stamm’s new 60 foot monocoque, better known by the name of “Cheminées Poujoulat”, which is due to take part in the forthcoming Vendée Globe 2012, we move on at the beginning of July to our next project, building the S2, code name for the new Solar Impulse airplane.

Once again we go from boat to airplane, but with our expertise in the use of composite materials as the common factor.

Even before the first flights of HB-SIA, our team at Decision SA were thinking about innovations that could be implemented in the new plane. We reached the stage of working on the lightest carbon fibres weighing only 90 g/m2 (by comparison the sheets of paper we all use daily weigh 80 g/m2) and we wanted to find solutions that we could put to the Solar Impulse design team to make the plane even lighter wherever possible.

The way forward came by taking recent developments in yacht sails by the company Createx of Cossonay and combining them with a new technology called TPT, or Thin Ply Technology. With this technology, we succeeded in laying down on our vacuum tables complex multiple layers of 25 g/m2, plotted by a robot guaranteeing absolute precision in the angles and positioning of the fibres. Incidentally, the CNT (Carbon Nano Tube) included in the new epoxy resin was developed and supplied by Bayer, one of the main sponsors of Solar Impulse.

To validate this new process we worked all through spring and, thanks to the intensive and productive collaboration among all those involved (the Solar Impulse Design Team, Createx SA, Empa and Decision SA), we came to the conclusion that this highly innovative process should be used in building the S2.

So here we are at the end of the year, with all the tools for manufacturing the wing spar completed, and in the process of making the braces for the spar which, when assembled, will be more than 70 m long.

The initial stages of this construction epitomise the mindset of those driving this marvellous project forward: a constant effort to find innovative solutions, to establish their reliability and then to implement them.

Hence the pleasure we all have at Decison SA in building the structures of this extraordinary airplane.

Bertrand Cardis