2008: HB-SIA taking form

This was an important year for Solar Impulse and its visionaries. Founders and pilots Bertrand Piccard and André Borschberg succeeded in the first virtual flights (25 hours each) as construction of the HB-SIA prototype continued.

May

• May 12: As the aircraft’s parts are built, André Borschberg and Bertrand Piccard will both undergo a 25-hour virtual flight each in a mock cockpit.  

November

• 27 November: Wing spar delivered in Dübendorf for the construction of HB-SIA.

December

• 5 December: Wing spar assembled.

We then began vibration tests. These consist of vibrating every part of the aircraft to measure its specific frequencies, for example by moving the wing tips by up to 50 cm. We had of course already measured these different vibration frequencies with sophisticated computer models. And despite the complex nature of these phenomena, the live measurements came out very close to our earlier calculations..

What difference does this make? Too big a gap would have required us to review the design and the structure We can now look forward serenely to the next set of tests planned for January.

A happy festive season to everyone.

One week after the wing spars were delivered to our Dübendorf hangar, we have finished assembling the 3 parts and can now (for the first time) contemplate the wing with its full 61 metre span! With the initial shock now past, I have to admit that we are already accustomed to this carbon structure invading our hangar, and are nearly used to its extraordinary dimensions.

Within a few days we will have fixed this wing to the cockpit, itself already attached to the fuselage and rear stabilizer. We will then have before us the first skeleton aircraft and be able to start extensive vibration testing, which I will be telling you about shortly.