Solar Impels

The project Solar Impulse aims at making take off and fly in an autonomous way, of day like night, a plane propelled exclusively to the solar energy, until carrying out a round the world tour without Carburant nor Pollution.

The pilots of Solar Impulse are with the orders of the project since 2003. It is about Bertrand Piccard, the adventurous psychiatrist, and André Borschberg, the pilot contractor. As of the first flights, they will share the missions, the which cannot apparatus, for the moment, to accommodate that only one pilot at the same time.

Great stages of the project

It is a project which falls under the duration:

Feasibility study with the Polytechnic school of Lausanne in 2003.
Development of the concept in 2004-2005.
Flight simulations long lives since 2006.
Design and manufacture of a Prototype in 2006-2007.
Flights tests and first night flight with the prototype in 2008-2009.
Construction of the final plane in 2009-2010.
Round the world tour in five stopovers in 2011.

The goal of the project is to make the round the world tour. Takeoff should take place in May 2011, for an overflight of the ground close to the equator but primarily in the Northern hemisphere. Five stopovers are envisaged, to change pilot and to present the adventure to the public and to the political authorities and to scientists. Each section of the flight will last from 3 to 4 days, which is regarded as the bearable maximum for a pilot alone. When the effectiveness of the Batteries makes it possible to reduce the weight of them, the plane will be able to very take on board two pilots for flights of long lives and a round the world tour without stopover will become possible then.

Aerodynamics

The scale of the plane is of 80 meters, that is to say slightly more than that of a380 Airbus, in order to minimize the induced Traînée and to offer a maximum surface to the solar cells. Such a weak wing load (8 kg/m2) implies a greater sensitivity to the Turbulence. The extra-light structure must use Carbon fibers specifically adapted.

Materials and structure

Whereas traditional the Sandwiches composites has a surface mass of about 10 kg/m ², those developed for Solar Impulse will have to weigh about 0.5 kg/m ². These materials could moreover be equipped with integrated functionalities such of the sensors of integrity, the active control of form, etc

A “skin” made up of ultra-thin solar cells S is integrated in the wings. These cells will be flexible to follow the deformations and vibrations of them and will have to be encapsulated to guarantee a maximum effectiveness under all the conditions, an optimal resistance to the external aggressions but also a structural contribution.

Energy

Like additional difficulty, the energy collected during the day will be not only used to propel the plane, but also to reload batteries to ensure the night flight. The pilot will have thus the peremptory necessity to find himself each evening with full batteries and to save to the maximum energy at disposal to hold the air until the following sunrise. Energy is accumulated during the day in batteries with lithium laid out in the wings and of which the density must approach the 200 Wh/kg, in spite of conditions of temperature varying of +80°C with - 60°C.

Propulsion

The average power over 24 hours placed at the disposal of the engines by the sun is practically equal (12 CV) to that the Frères Wright in 1903 had when they carried out the first flight in the plane of humanity. Success can thus pass only by one optimization of the outputs and a general reduction of the weight.

Cockpit

Because of the still excessive weight of the batteries, the cockpit will be able to accommodate only one pilot, who must be able to operate up to 12.000 meters of altitude, under extreme conditions of pressure and temperature. The cockpit will thus be equipped with various systems: Pressurization, oxygen diffuser, elimination of CO2 and the moisture generated by the human body. These devices will have them to also be extremely modest in terms of weight and energy consumption in order not to penalize the needs for the propulsion.

The realization of the project is ensured by a partnership between several companies and institutions whose principal ones are:

On the level of Principal Partner: Solvay, Omega and Deutsche Bank
On the level of Official partner: Altran
On the level of Scientific and Aeronautical Partner: FPSL, the European space agency (ESA) and Dassault

External bonds

Official site of Solar Impels
Solar Impulse with FPSL

Random links: