Sadly, here we go again
In all honesty I never thought they would get this far and I have nothing but admiration for what has been achieved. Without a major benefactor this project has never had a long term future. Maybe, just maybe, one will still be found. I certainly hope so. There are plenty of people in this world to whom £5M £10M £20M is nothing. Maybe one will feel this is their baby? However the chances are getting less. I've spent all my life working in the museum field. Generally it is much easier to raise money to acquire something new or build an extension than to keep something running.
One of the problems with the Vulcan project was that it was not (nor could it be) for ever. Say Mr Mega Rich had written out a cheque for £10M at the start. With careful management that would have got her in the air with sufficient funds to operate for X years. But would it? Once there is a large sum in the bank people tend to look at projects differently. Costs would have risen and fewer people would have worked for nothing. So, perhaps it would have needed £15M, maybe £20M. But what does Mr Rich get for his money? A static exhibit in a museum 15 years later than it would otherwise have happened.
Also, at the moment XH558 draws the crowds. It is “new” on the airshow scene. Realistically, even if the running costs are found, it will not be quite such a draw in 5 years time. Maybe somebody will have found a way to get, say, a Lightning authorized to fly in the UK by then. That will be the new kid on the block and XH558 will be old hat. I suspect this is the view that would be taken by some potential donors. The project does not leave a legacy for their money.