For JFM re: L-39 Albotros
The aircraft is privately owned, registration, which is visible under the horizontal stabiliser is C-GOZA. Owner is unknown. It appears regularly at Comox, but is ,I believe registered in Alberta. There is no USAF presence at Comox, and if he is playing the aggressor role for the USAF, it will be by private contract, about which I would know nothing. If so why would he fly from a Canadian airport.
Here is a url to better pictures of the a/c in Alberta.