Leave Steiner's workshop and double back using the same road (double back using the small street, turn right at the junction, then turn left) to return to the tavern.
Captain Obo can be found in the bottom left corner of the room (next to the chimney). Talk to him. Unfortunately, Kate won't be able to reason with him, as he is deep into the bottle. Approach the counter to speak with Sara and the owner of the tavern. Follow their suggestions and talk to captain again (he'll sober up a bit). To convince him right away, choose the following dialogue options: 3, 1, 3, 1, 1 (if you were successful, you'll be rewarded with an achievement - Crime and punishment). However, if you were unable to convince the captain, you'll need to supply him with additional reason.
Leave the tavern and make your way to the ferry (turn left, then proceed down the coast and use the wooden stairs to get onboard).
Use of one of the available doors to enter the quarter-deck and proceed up the stairs to find the bridge.
Approach the table found in the southern part of the room (the table is opposite to a stillage with the phonograph) and pick-up Captain Obo's log book. Read through its contents, and return to the tavern to make another pass at the captain. This time, Kate will be successful - the captain will leave the tavern and proceed to the ferry. Return to the bridge and access its upper part (the one with the steering wheel). Talk with the captain to learn that the ship needs a coal supply and you receive captain Obo's paper with access code - you can access the hangar and the crane.
(If you go to the ferry in order to get the journal before you meet with the captain in the tavern and then you start the conversation with the knowledge about his past, which can be used during the dialog - option no. 2 - you get Martingale achievement. The achievement can also be acquired in, at least, two other parts of the game that takes place later).
Leave the ferry and head to the tavern where you must speak with the captain again. This time Kate manages to convince him - when the captain leaves the place you can do the same and go to the ferry. Enter the quarterdeck and climb on the bridge. You learn that you must deliver coal to the hold and you also receive a paper with captain Obo's access code - use it to open the hangar and use the crane.