A variation on this excellent scheme from: https://bonecron.blogspot.com/2019/06/titanicus-terrain-painting-tutorial.html

1. Prime with citadel Grey Seer
2. Base with 1:1-ish mix of :Proacryl 1step Bright Slate Grey/Graphite Grey:
3. Drybrush with Neutral Grey
4. Drybrush with Bright Neutral Grey
5. Paint pipes with Bronze
6. Paint roof hatches/fans/electrical boxes with :vallejometalcolorexhaustmanifold
7. Paint wings/aquilas with :proacrylrichgold
8. Paint little circles and random door trim with :proacrylcopper
9. paint windows with heavily thinned Asurmen Blue (3:1?)
10. Paint roofs with :proacryl/1stepdarkgreenblue