In Chapter 36, DeWitts only objective is to find a way to reach the top deck of the ship. However, the task isnt easy to accomplish, because the path is filled with all sorts of enemies.
The following collectibles guide details the location of the BioShock Infinite collectible available in Hangar Deck, and since the ships exterior can be misleading, players are encouraged to use the guide to their advantage.
Once you reach the Hand of the Prophet flagship, Elizabeth tells you that the only way up is by using the sky-line.
However, the sky-lines are blocked by patriot pods and you need to find a way to clear them off. Once youre done, ride the sky-line up to the next deck.
On this deck there are two locked doors, one that requires one lockpick and one that requires three lockpicks. Find the door with one lockpick, near the control panel for the pods that block the second sky-line.
Head inside and get in the room past the headless patriot to find the BioShock Infinite Hangar Deck Voxophone on the desk.
WHATS DONE IS DONE; Rosalind Lutece; September the 3rd, 1909
Clear the sky-line and then use it to reach the next deck. Access the 3rd deck interior to start the next chapter, Engineering Deck.