I did see something on Sky last year where a pulse laser was used to propel a small vessel into the air. Not much use for every day flight but useful for going up and into orbit.
Perhaps we will only use oils for a booster to get an aircraft up to Scramjet speed then inject some organic fuel such as turnip juice etc?
Reactors will no doubt have massive flight safety issues attached and all the pinko green types would be up in arms near local airports!!
I do think the time for research is now though, and if found we should switch as aircraft are often overlooked as massive CO2 etc polluters