it's a matter of efficiency (Score 1)

An aircraft that runs on fuel has to carry said fuel, therefore requiring more fuel to carry the fuel itself. Even if the laser is powered by an base generator running on fuel, it will save fuel by removing the power cost of carrying the fuel on board the aircraft. Also the laser allows powering the aircraft with out having to land. That will eliminate many takeoffs which are the most fuel expensive part of the average flight. And the on base generator could run on far lower grades of fuel than JP5 saving more money. A on base generator, as opposed to an aircraft engine, also will optimized for efficiency instead of weight. Finally, imagine running this off a nuclear powered aircraft carrier. That would have massive fuel savings. Food for thought.