In the classic science fiction movie Aliens (1986), directed by James Cameron, Colonial Marines Drake and Vasquez are equipped with a squad automatic weapon called a M56A Smartgun. The weapon is attached on a swing arm to a hip mount.

The M56A serves in the squad automatic or MG role, with a high rate of fire. Not only is it counterbalanced for ease of use, but also has an eye piece for targeting.
But why is the weapon called a Smartgun? It’s use in the movie doesn’t explain that part.

A relatively recent book (2016), called the Alien Weyland Yutani Report (S.D. Perry), collects color photos, diagrams, and in-universe commentary about the Aliens moves, written from a “Corporate” perspective. It covers the movies up through Prometheus, but not Covenant.
It’s still easily available on Amazon.
Check Wayne’s Books inventory for ALIENS stuff
I spotted a two-page spread about the M56A, just after the more familiar M41A Pulse Rifle.





See also:
Did you know there were 1980s Aliens RPG, board game, and metal miniatures? Visit my RPG Reference page for Aliens
Traveller 2300 : Three Centuries after a Global Nuclear War, Humanity Reaches for the Stars (1986) – Want a similar sci-fi RPG campaign universe, minus the all-consuming Aliens?