[mhcarlin (OP)]

it's feasible.

[another_someone]

it's feasible.

In what way are you thinking the aircraft fuel is unsafe (I am not saying you are wrong, I am merely wondering what the focus of your concern is, and what aspects you see as greater risks than others)?

Things that can be done today is the use of self sealing fuel tanks (I believe this was implemented on Concorde very late in its life, after the Paris air crash; and is common on military aircraft that are likely to get bullets through the fuel tank).

Generally, the use of heavier fuels (such as diesel) reduce the likelihood of combustion, but are not presently suitable to aircraft engines.  Whether other additives can be included to reduce fuel vapour (it is the vapour that is usually the trouble, not the liquid fuel) is another matter - but then you have to make sure you can properly vaporise the fuel when ignition is required in the engine (which is why diesel fuel will not work).