I've thought about it many times.
Then realised that in our industry the benefits are tenuous, whilst I could buy and read all the textbooks for well under £1k, leaving the other £20k of the course fees to blow on hats. Or borrow them all from a good library, allowing me to spend the £1k on beer.
It *may* be useful for somebody who has no management experience, but considerable industry experience, and wants to make that sort of career move. Maybe. I'm not convinced - personally I think that you're more likely to get a management job on the back of a good specialist MSc from somewhere like Cranfield.
There are however if you're interested, some specialist aviation management MBAs - Brunel's one is obviously targetted at the Heathrow community for example. Being serious, I've no doubt that this study would allow me, or many other aviation managers, to understand our jobs better. But, equally taking the time to cherry pick and self-study the important stuff, would be much less expensive of time and money, and probably work as well - for me personally.
I asked my wife the question (she does have an MBA) and she reckons that the biggest benefit is the year-long networking opportunity with the people who may be significant in your industry over the next 5-10 years. I'm not sure I buy that either - that could perhaps be obtained through active membership of RAeS committees, or the specialist MSc again?
G