"shootdown of a Gazelle" . . . "1990 Gazelle shootdown" . . . . . . . "1990 British Army Gazelle shootdown" . . . . "A British Army Gazelle helicopter was shot down by the PIRA's East Tyrone Brigade" . . . . "on 11 January 1990" . . . "11 January 1990" . . . "between Augher and Derrygorry" . . . . "British Army Gazelle shootdown" . . . . "brigade managed to shoot down" . . "Gazelle" . . "United Kingdom" . . . "1990 British Army Gazelle shootdown" . . "Derrygorry Army Gazelle downing" .