Overwatch's Retribution archives event has a few sections in which enemy troops drop in from gunships/dropships at certain parts of the map, most notably in the end sequence. When shooting these dropships, hitmarkers do activate, and it seems like some fire and sparks start appearing around the engines.
It begs the question; can these gunships be destroyed completely? I have not had the opportunity to play a character with the potential damage output to do so (Bastion), so I'm not too sure.
Best Answer
I've tested this with a Bastion, and even though he causes dropships to very quickly start burning, I've never been able to take one down, either before or after it releases enemies.
Hoever, in the event's final area, some dropships will release two waves of enemies. It is possible to force a dropship to retreat after the first wave of enemies by dealing enough damage to it.