CA, what you say is true to a point but I disagree that the A46 has the capacity. I was not thinking of the air show but regular museum traffic. The A15 might be straight but is otherwise pitiful. I agree the motorway access is good but that is why the A15 is inadequate.
The hangars are an issue. If they are listed and I can't think why as they are not unique. A!ing the ridge you have Kirton Lindsey, Hemswell, Scampton, Waddington, Digby and Cranwell - take your pick. Or Binbrook, Manby, Cottesmore. Then I believe there is no requirement for the MOD to either maintain or retain a listed building.
Many might not like Hendon and think it too far away, but I would bet they have a much more populous catchment area and a greater footfall.