Remain when in trouble - these fly (6)
I believe the answer is:
airmen
'these fly' is the definition.
The definition suggests an adverb but the answer is not.
'remain when in trouble' is the wordplay.
'when in trouble' indicates anagramming the letters.
'remain' anagrammed gives 'AIRMEN'.
Can you help me to learn more?
(Other definitions for airmen that I've seen before include "Pilots" , "serving in HM forces?" , "Daedalus and Icarus for example" , "Some engaged in 7 [NATIONAL SERVICE]" , "they take off from the ground" .)