Secret plane

Maybe he saw a Typhoon, but that doesn't explain why he said his camera runs out of juice when he tries to snap it, does it?

Actually the millitray plane have this anti-camera thing going on (at least in the US they do) because if you try to take a picture of a plane in San Diego (lots of millitary plane there if you didin;t know) then your film will come out black. Doesn't make sense how they do that unless your camera falls under the "harmful/unharmful interference law" stated on the camera or near it somewhere.

I think unless you have hard evidence of these 'black triangles' you claim to have seen, then its pointless to go on about it. I could say I saw a blue flying elephant & have the same evidence as you, as I say nonsense.
If things are happening at say RAF Macrinhanish, they go straight out to sea, NOT over UK land.