Doesn't necessary need to be an issue of ALPHA FLIGHT, but may be Alpha Flight related (maybe where Mac appeared in UXM #109, or where they were guests in ROM or whatever).
For me, I think UXM #121 is still my favorite cover (it was a battle between that, and issue #1 and #3 or #4 - with Aurora on the cover?)
But I think since this was my first introduction to Alpha Flight, and it's a pretty cool action cover - this is just special to me.