CNN Documented July 20, 2014 00:09:00
If the missile hit there why does the missile section appear intact? >> the missile throws debris at the aircraft. it explodes before it hits and impacts, so with that a case to me, those pieces of debris separated the tail from the aircraft. so the aircraft was -- the tail was gone before the aircraft went down or caught on fire. so this piece of the tail is where you would find the black boxes. if the black boxes were in that tail, though, there's a possibility they broke loose from the aircraft at that point. if that happened, they could be anywhere up around the countryside. they're heavy ...
Source: archive.org