I think it is just Team Plasma's boat that they used to get from city to city. I can't be too sure but it's not like the others that you can go to places on. So I don't think it's that important tbh.
Hope this helps. :)
^ I'm going to correct this person's verison.
The black boat is in fact Team Plasma's boat, and it does come into the game.
If you get a Liberty Pass (no longer available, but was obtainable over Nintendo wifi) and go to the Liberty Garden, Team Plasma is there. They have heard that a legendary Pokemon named Victini is on that island and they plan on catching it. You will have to defeat all the Team Plasma members and then catch Victini for yourself (it's at level 15)
Then, when you go outside you will see Team Plasma getting back into their black boat, they are being kicked off the island. Afterwards, Professor Juniper will appear to thank you.
hope this answers your question. :)
A boat owned by team plasma
It's Team Plasmas boat!
There is none in pokemon black.
you cant on pokemon black
Dawn is not in pokemon black.
Zekrom (Pokemon White) and Reshiram (Pokemon Black).
traveling
You can't.
To take team Plazma to liberty island.
It's Team Plasmas boat!
I have a feeling it is the boat u ride to the p2 lab for the genesect event.
Well I don't think you can actually get into the black boat as it is Team Plasma's. I'm not sure though but it doesn't seem like you can.
go on it and find out.
in castelia city, city with boat to victini
It doesn't do anything that I am aware of, as it is Team Plasma's boat which they would use but it doesn't do anything and you can't board it.
The black boat that can be found located to your left on Prime Pier in Castelia City does not go anywhere and serves no purpose in the game.
black boat = schwarzes Boot
You can't. It belongs to Team Plasma, but it doesn't really do anything.