Actualités

Pushing the limits is a tough job, but it’s a necessity when innovation is the ultimate goal. The problem is that it’s hard to know ahead of time where the limit is. Solar Impulse crossed that thin line last year, on July 5^th, 2012, during the structural test of HB-SIB’s wing spar – the central part of the second solar airplane’s wings. We got too close to the edge and fell overboard: i.e. the wing spar broke. Only by persevering and learning from one’s mistakes can innovation happen. In fact, this is the attitude that made it possible to build the first solar airplane able to fly day and night with the wingspan of a Jumbo Jet, the weight of a small car and an almost limitless endurance.

The new wing spar was delivered July 19^th, 2013 in Dübendorf. The engineers had no time to lose and immediately began preparations for the upcoming tests of this very large and bulky part (over 70 meters in length). The first one, a torsion test and also the most difficult one, took place on Monday August 5^th. Solar Impulse engineers decided to start with the one that had caused the first spar to break in order to instantly know whether the new structure would be able to handle the load. Nothing in the configuration of the test was changed. In fact, the analysis done after last year’s incident proved that the load cases, test jigs and overall setup were indeed correct.

This series of tests will be completed by the end of August from which point the “dressing” of the wing will start. Solar panels, ribs, fabric and motor gondolas will be added to the structure bringing the solar wings slowly to life…

Source: Solar Impulse