In cases like this, it’s probably best to let the video speak for itself: [youtube]http://www.youtube.com/watch?v=ueWCnmyH9g8[/youtube] The guy sitting on the plane in the above screen grab (and, in the clip’s opening shot, fixing a fence with a rake while wearing a tuxedo and drinking a martini; we told you it’s best to let the video speak for itself) is F-18 pilot Lt. Clayton Heyward. His YouTube proposal to superstar recording artist Katy Perry — in the form of a parody song set to her hit “E.T.” — is a simple one: Make the trip from Hollywood to Fresno, Calif., and…