died, according to the u.n., with that number expected to now rise significantly. the number of military casualties is not clear but is said to be considerable, as the report by ivan watson in the last hour from a ukrainian cemetery illustrated. the ukrainians remain significantly outgunned in the air. ukrainian pilots are more than answering the call. >> reporter: counted out early in the war but still going strong. against all the odds, russia has not managed to ground ukraine's air force. we spoke to fighter pilot andrei, who was in an undisclosed location and hiding his identity for safety locations. >> translator: at first, russian pilots dominated in quantity of fighters and equipment. now they're starting to refuse to fly because we're shooting