What is REALLY in Hangar Eighteen?

It disappoints me, also, that the military will not allow this information to citizens. Anyone who could tell you the answer would either have to kill you afterward, or the Air Force would come around to kill you yourself. The question is, is it right for them to hide this information? Whatreally happened that night? My brother is in the Air Force; He goes to Wright-Patterson every day. I believe he knows, but he would never tell.