FS9 Drop Tanks

[MaddogK]

I'm sure this has been covered many times before but as the the forums are almost new again, and I can't find the info in the SDK's I'll ask again:

I want to put droppable fuel tanks on a model I'm creating but unsure if the tanks require a special part 'tag' or are the tanks part of a seperate LOD model ?

Is there a tut somewhere ?

Thanks in advance.