submarine invisible helipad equivlant?

[kdk11 1]

anyone know a way of using something like the invisible helipad but for submarine's? as transport unload wont work without one.

[kdk11 1]

bump*

[TGxAltair 10]

I use the invisible helipad for unloading boats, just use it for the submarine.

[l etranger 5]

Can't you put a invisible helipad under water?