UKPatternflyer,
The link to the P-17 flight above is this:
https://www.youtubeXXX.com/watch?v=4enIHyWH1SE
(remove the XXX in the link)
Copy and paste that adress and try it in some different browsers You can use and see if it works then.
For me the link works in IE 11, Edge, Crome and Firefox.
/Bo