OK Crab, I'm beginning to realise that there are those that can't be persuaded and those that won't be persuaded.
You're using some pretty strong terms:
("why blow £300K of it on doctors?", "more likely to stay and play at the scene"),
relying on second-hand, subjective evidence:
("Of the medical professionals (including doctors) I have talked to, most seem to think that doctors on AA will have a limited and possibly negative effect", "a small benefit for one or 2 patients")
and indulging in some fairly heavy-handed unfounded speculation:
("It seems the charities are sitting on a huge pile of cash and are looking for ways to spend it quickly so people don't ask questions or stop donating").
Finally, you haven't moved from your stance that the whole thing is an NHS issue:
("I believe the money would be better spent in other areas of the NHS, regardless of the fact the taxes are supposed to provide these services. The charities could donate funds or sponsor extra posts or provide buildings/renovations where the NHS trusts are overstretched.")
From the top:
Charities are far more accountable to their donors than the NHS, or the MoD for that matter. Furthermore, if charities were to be seen to be frittering money away then people would simply stop donating. If only the same could be said for Gov't funded organisations like the 2 I've just mentioned...
Doctors working in the properly-structured environment that exists in places like London, Kent et al don't "stay and play" - they provide appropriate treatment and ensure that the casualty then gets the further care he/she requires.
Try talking to medical professionals who actually know, from first-hand experience, what working in such an environment involves. Better yet, try listening to what such doctors might have to say.
Charities have a responsibility to their donors, as alluded to above, to ensure that any surplus funds are allocated in the best manner possible. If a charity sees a way to improve an already-excellent service then it is their duty to do so.
Finally, they're called "Air Ambulance" charities 'cos that's where their money goes. People give them funds in the knowledge that they will specifically spend the money on a means of getting rapid intervention/treatment/extraction on the fortunately-rare occasions when things all go horribly wrong. Should the Charity Commission or whatever it's called this week catch such an organisation donating money to prop-up NHS building shortfalls or whatever there'd be hell to pay - quite rightly. If you haven't gripped the difference between medical services people expect from the Gov't (the NHS) and medical services funded through other means ( eg BUPA, Air Ambulance charities) then we're not going to get anywhere 'til you do.
OK - you think the NHS should have more funds and you don't think money should go to Air Ambulances so that they can "up their game". Fine, help vote in someone who'll sort out the Health Service and only donate to charities that don't have properly-trained, supervised doctors on board. However, let those who've done the research, tried the alternative and found it better get on with their work without the sniping, eh? Oh, and crack on with the excellent SAR stuff you folk do so well - much appreciated.
ps - were you a student of mine at Shawbury? I seem to remember chatting to someone with your debating methods between 1984-6