The plane crashed into jumbo (8)
'jumbo' is the definition.
'the plane crashed' is the wordplay.
'crashed' is an anagram indicator.
'theplane' is an anagram of 'ELEPHANT'.
'into' acts as a link.
(Other definitions for elephant that I've seen before include "The animal that never forgets", "Trunked mammal", "See 18", "Trunk carrier?", "Endangered Species".)