Arson affected navigation aid (5)

I believe the answer is:

sonar

'navigation aid' is the definition.
(I've seen this in another clue)

'arson affected' is the wordplay.
'affected' indicates an anagram.
'arson' anagrammed gives 'SONAR'.

(Other definitions for sonar that I've seen before include "Device for detecting objects used in arson" , "Underwater detector" , "System for locating underwater objects" , "Means of detecting" , "What a near-blind creature uses" .)

I've seen this clue in The Mirror.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.