WASHINGTON: The U.S. Air Force has decided to push development of a new type of fuel to power its bombers and fighters, mixing conventional jet fuel with nonpetroleum-based fuels that could eventually end military dependence on foreign sources of oil.

The plan, to be announced at the Paris Air Show, will open a contest between fuel refiners and alternative energy companies to produce a jet fuel composed of no more than 50 percent petroleum. Reflecting the importance that the U.S. government attaches to the initiative, the public announcement will be made by U.S. Air Force Secretary Michael Wynne and U.S. Federal Aviation Administrator Marion Blakey.

"The goal is to certify the entire fleet by 2010 with a 50-50 mix," said Air Force Special Assistant Paul Bollinger who is coordinating the military shift to synthetic fuels.

As far as I know, the only 50/50 blend tested so far (with a B52 bomber all 8 engines) is based on gas and coal liquefaction (Fischer-Tropsch tech).

Any decision by the US air force will have a big impact on civil aviation. They are subsidising the the R&D by  ordering the first large deliveries for their tests.

I'll try to catch that announcement in Paris and see what their intentions are.
Just a bit scared that this news will be burried among the show and will be hard to find.

The struggle of man against tyranny is the struggle of memory against forgetting.(Kundera)