From Fallen London Wiki
The maps also require 5 <a href="/wiki/Services_Rendered:_Zailors" title="Services Rendered: Zailors"><img alt="" src="/w/images/thumb/3/3c/Crew.png/20px-Crew.png" decoding="async" width="20" height="26" srcset="/w/images/thumb/3/3c/Crew.png/30px-Crew.png 1.5x, /w/images/thumb/3/3c/Crew.png/40px-Crew.png 2x" /></a> <a href="/wiki/Services_Rendered:_Zailors" title="Services Rendered: Zailors">Services Rendered: Zailors</a>, which is what takes an average of 12.5 actions.