Plane crashed in mountainous country (5)
I believe the answer is:
nepal
'mountainous country' is the definition.
(I've seen this before)
'plane crashed' is the wordplay.
'crashed' indicates an anagram.
'plane' with letters rearranged gives 'NEPAL'.
'in' acts as a link.
(Other definitions for nepal that I've seen before include "Mountainous country" , "mountainous area" , "Himalayan kingdom" , "Gurkhas' homeland" , "neighbour of Tibet" .)