There is a lot to be said for mahogany bob's suggestion ; if it is to be done outside, let it be done by people who routinely train large numbers of staff, fairly efficiently, and also could provide some useful incentives.
I found Lima Juliet's response / explanation to Timelord fascinating, hilarious and depressing - with all the 'creamies' and 'skimmies', 'swim lanes' etc. Thank you LJ. Reading that makes it depressingly clear why the system is having trouble. It is far too complicated - possibly because it has grown orgaincally over mnay years, perhaps for some it is 'hallowed' by tradition and of course has been messed up by efforts like the DSDRs. It needs simplifying and a complete reset. BA, whoever owns them, could do a darn fine job at it; their safety and their airworthiness record is fairly good...
It is not that complex. You are training people to fly, operate and maintain aircraft - OK 'air systems' to allow for the drones - and their various supporting services and processes. That's it. That's all. Most really large companies do this sort of thing routinely, some in-house, some contracted out. If they beahved like the RAF, they'd be long gone.
And no, 'security' considerations are not an excuse. Large multi nationals deal with both their own and others' commercial security matters as well as nations' security issues as necessary - routinely and generally well So forget that one. None of what the RAF does in terms of trainiing is particularly difficult of itself; it has just been allowed to grow admin and business BS for too long - mimicking so much the MoD appears to damage!