The last Chivenor Open Day, with fixed wing participation, as far as I am aware (Not Air Day, as it is a RM base:-)was July 2000. As is always the case, the weather the day before was glorious, with a couple of Hunters demonstrating the 'Blue note' in a pre-match practice, set against a beautifully blue, clear, N. Devon sky.
The actual day was classic warm sector conditions with a limited flypro; Tonka, Tucano, Sea King (of course) Merlin 3, some vintage participation and others, (sorry, can't remember them all). The Red Arrows had to divert into St Athan? due to wx, and one of the team had a major engine snag on the way down with a diversion somewhere else. The Army and RM also done good with some top static military stuff.
As a result of the poor weather, the crowds were well down on expected numbers and financially it was a close run thing. As I recall, the runway was declared unfit for further use by FW soon afterwards, as it was breaking up. I would be suprised if there is another Day like it, as it costs a lot of money to put on.
That's it, there is no more!