There is another problem. A FF using p+11B reaction will produce some high energy gammas. About .1% of the energy output or so, ie about 6kW of gamma in the MeV range. Even if the rate is less by a factor of 10 that is still a lot of radiation. These will need far more than a 1 meter of shielding. Even a meter is too much for the weight of an aircraft.
I can’t see p+11B flying. It makes more sense to use a big power station to create jet fuel out of air and water.
