Plane crashing close to India in mountainous territory (6)
I believe the answer is:
nepali
'in mountainous territory' is the definition.
(in or relating to Nepal)
'plane crashing close to india' is the wordplay.
'crashing' indicates anagramming the letters.
'close to' says to put letters next to each other.
'india' becomes 'i' (phonetic alphabet: alpha, bravo, charlie etc.).
'plane' with letters rearranged gives 'nepal'.
'nepal'+'i'='NEPALI'
(Other definitions for nepali that I've seen before include "Native of one Himalayan state" , "Foreigner" , "Native of a mountainous Hindu kingdom" , "Language of Kathmandu" , "one found in mountainous region" .)