Pilot uses infrared navigating to capital city (7)

I believe the answer is:

tripoli

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'to capital city' is the definition.
(capital city of Libya)

I don't understand the remainder of the clue.

(Other definitions for tripoli that I've seen before include "Libyan city" , "North African port" , "Middle East port" , "Place in Libya" , "North African city" .)

I've seen this clue in The Irish Times.

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