solar war planes

en.wikipedia.org...

The Solar Impulse project aims to have a plane powered exclusively by solar energy take off and fly autonomously, day and night, to the point where it could circumnavigate the globe with no fuel, generating no pollution.

The pilots of the Solar Impulse, Bertrand Piccard, psychiatrist/adventurer, and André Borschberg, pilot/entrepreneur, have been leading the project since 2003. Beginning with the first flights, they will share the missions, as at the moment the aircraft can only carry one pilot at a time.

THE MAJOR STEPS

This is a long-term project:

• Feasibility study at the Ecole Polytechnique de Lausanne in 2003.

• Development of the concept in 2004-2005.

• Simulation of long-haul flights as of 2006.

• Design and manufacture of a prototype in 2006-2007.

• Test flights and first night flight with the prototype in 2008-2009.

• Construction of the final plane in 2009-2010.

• Missions of several days, crossing the Atlantic and trials circumnavigating the globe with five stages in 2011.

Take-off should occur in May 2011, for a flight around the world near the equator, but essentially in the northern hemisphere. Five stops are planned to change pilots. Each leg will last three to four days, which is the maximum time one pilot alone can handle. Once the efficiency of the batteries makes it possible to reduce the weight, the aircraft could carry two pilots for long flights, and a trip around the world without stopping will be possible.

My question is why is the military not investing in technologies like this? It would save an enermouse amout of fuel resulting in huge savings. Especially when you think about the new solar cells that can now achieve 40% energy conversion rates. You could generate a huge amount of powere especially on the huge transport planes.

Maybe because it's slow, and it may be awhile before they ever get faster.