Locomotion Commotion Achievement

Note: If playing in co-op, this does unlock for both players.

This is unlocked in Mission 4, ‘War Factory’. In the southwest part of the map is a tall crane on top of a building overlooking train tracks. There is a person inside its control room, and shooting them will cause the crane to malfunction and drop explosives onto a train below, which will unlock this achievement.

If you missed this while playing the mission the first time, and have unlocked all the starting positions, the closest starting point is ‘Trainyard Office’. From there, the crane is just a short distance away to the south.