Chug
You repeatedly state that the MOD, MAA and MilAAIB must be separate and independent of each other. For civil aviation, the AAIB and CAA are independent of each other but both belong to the Dept of Transport and answer to the same minister. (Yes, EASA is an added layer, but it is DofT that acts on behalf of the State with EASA, not the CAA.)
I am not quite clear how you think an independent MAA would be able to compel the MOD - a Department of State - without elevating its ownership to Cabinet level. And if you put the MAA with the CAA in DofT, you then have the spectacle of an OGD telling the MOD what its spending priorities are, which would definitely not be a good thing. This is not the same as Treasury having a say in affordability or budgetary control.
I can see there may be an argument for separating the MilAAIB from the MAA, though again I am not sure where you would put it, but you still end up with the risk being held by SofS as the point where all this meets.
For now, you have an MAA (and a DG prepared to say what he thinks) that is at least independent of the single Services and answerable through PUS to SofS. I do not see how you are going to get a better arrangement by taking the regulatory function outside the MOD, when control of their own specialist regulation is a core function of all Govt Departments.
I think what we may all be agreed on is that key safety measures should be treated separately within the overall resourcing process.
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