Friday December 21, 2007 : Solar Impulse, launch of the construction of an initial prototype

Altran is engineering partner of Solar Impulse, a project that aims to fly a plane autonomously propelled uniquely by solar energy. A Franco-Swiss team of consultants from the Altran Group is playing a key role in the project's team.

After four years of research, studies, calculations and simulations, the Solar Impulse project has entered a concrete phase with the construction of an initial prototype with a 61-metre wingspan, referred to by its registration number “HB-SIA”. Its mission is to verify the working hypotheses in practice and to validate the selected construction technologies and procedures. If the results are conclusive, it could make a 36-hour flight - the equivalent of a complete day-night-day cycle - in 2009 without any fuel.


The technological partnership team

Two airplanes on the way to success
Construction of the first prototype, the HB-SIA, began in June 2007 and will last until the summer of 2008. Test flights should start in autumn 2008, with the objective of completing the first night flight in 2009. Another plane will then be developed to attempt to fly several 24-hour cycles consecutively, leading to the first trans-Atlantic flight in 2011, and then the first round-the-world flight.



HB–SIA’s mission
This is a “basic” prototype airplane. The instrument panel will be reduced to the essentials, and with a non-pressurized cockpit it will be unable to fly above 8,500 m. It will be a first approach at optimizing the balance between energy consumption, weight, performance and controllability. The goal is not to try to fly around the world and indeed the HB-SIA is not built to do so.

The objectives at this stage are:
• To validate the computer simulation results, the technological choices and the construction techniques.
• To test an unexplored area of flight: never before has an airplane succeeded in flying with these size, weight and speed characteristics.
• To store sufficient solar energy during the daytime to demonstrate the feasibility of a day-night-day cycle (36-hour flight).

More information about this partnership