tail assembly vs empennage

tail assembly and empennage both are nouns.

Word	Noun	Adjective	Verb	Adverb
tail assembly	Yes	No	No	No
empennage	Yes	No	No	No

As nouns, tail assembly and empennage are synonyms defined as:

Other synonyms of tail assembly include tail.

tail assembly (noun)	empennage (noun)
the rear part of an aircraft	the rear part of an aircraft