Fischer-Tropsch derivedfuels for aviation have been produced recently for the Department of Defense by U.S. based Syntroleum, and have been successfully tested by the US Air Force in a B-52 jet with all eight of its engines fueled by the mixture.
Certainly, greenhouse gas emissions are not the only consideration to be borne in mind in choosing a particular biofuel, and there is the matter of production-costs and the feasibility of making the fuel on the large scale, if any significant substitution for petroleum-derived fuels is to prove practical.
The air force is working to certify all its aircraft to use synthetic fuels made from gas derived from coal or biomass, using the Fischer-Tropsch method used by Germany during the second world war.