Hind - ground crew
Those "little guys" march purposefully around your base, armed presumably with Kalashnikov AK-47's and add considerably to the atmosphere.
The Jane's USNF series had the first ground troops I can recall seeing in a flight sim, but they were 2 dimensional bitmaps, all that was feasible for home computers to render at the time.
These ground crew and combatants in Hind have fully articulated legs and actually walk!
Now this may not have much to do with flying the chopper, but it demonstrates that DI were at the bleeding edge in the sphere of creating complex sim worlds in 1997.
The cargo doors work, and you can load and unload troops.
Unlike the western equivalents of the Hind, the AH-64 Apache and AH-1 Cobra), the Hind carries 8 fully armed troops or 4 stretchers in addition to the pilot and gunner.
Some of your missions involve insertion and extraction of troops. In the mission I tried no one came to the party! Oh well. Anyway some bloodthirsty virtual test pilots found early on that if you open the doors in flight, then shake the stick about those poor little guys will fall out .... can you believe it?