Crew plans means to embark on a voyage (8)
I believe the answer is:
gangways
'crew plans' is the definition.
The definition and answer can be both man-made objects as well as being plural nouns.
Perhaps there's an association between them I don't understand?
'means to embark on a voyage' is the wordplay.
'means' becomes 'ways' (I've seen this in other clues).
'to' says to put letters next to each other (I've seen this in other clues).
'embark on a voyage' becomes 'gang' (I can't justify this - if you can you should believe this answer much more).
'ways' put after 'gang' is 'GANGWAYS'.
Can you help me to learn more?
(Other definitions for gangways that I've seen before include "Movable bridges for boarding ships" , "Passages going on board" .)