Possible to add "unknown" ships to the rec manual?

[Von Due]

Some ships that appear in the game, do not appear in the recognition manual. Ships like submarines and lightships. Looking at the submarines folder I saw they have no sil.tga file.

Is there a way to add the necessary files to whatever other folders so that these ships appear in the rec man, and can be identified within the game mechanics like the other ships?

EDIT: Speaking of light ships. Any idea where the folder for those are? They have the class code LGH but I can't find the folder with the other data in it.

EDIT 2: It seems
submarines are UnitType=200
light ships are UnitType=105

Not sure how this relates to which ships will show up in the rec man.

[Sailor Steve]

Lightships aren't ships in the game at all, but environmental objects. Not only are they not in the recognition manual, but your crew can't see or identify them. This is why they always have a tug parked nearby, so your crew will report that ship to you.

[Jimbuna]

An example.
http://i.imgur.com/WyUHrYa.jpg

[Von Due]

Lightships aren't ships in the game at all, but environmental objects. Not only are they not in the recognition manual, but your crew can't see or identify them. This is why they always have a tug parked nearby, so your crew will report that ship to you.

Aah! Thanks heaps for the explanation.