Expedition travelling west in khaki kit - no knapsacks (3-4)
I believe the answer is:
'expedition' is the definition.
(1947 expedition across the Pacific Ocean)
'travelling west in khaki kit no knapsacks' is the wordplay.
'travelling west' is a reversal indicator.
'in' indicates a hidden word.
'ikitnok' is hidden in the letters of 'khaki kit no knapsacks'.
'ikitnok' backwards is 'KON-TIKI'.
(Other definitions for kon-tiki that I've seen before include "Thor Heyderdahl's raft" , "Thor Heyerdahl's raft" .)