With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: McDonnell Aircraft merged with Douglas Aircraft Company.
text_B: The Douglas Aircraft Company was an American aerospace manufacturer based in Southern California .. Aircraft. Aircraft. aerospace manufacturer. aerospace manufacturer. Southern California. Southern California. It was founded in 1921 by Donald Wills Douglas , Sr. and later merged with McDonnell Aircraft in 1967 to form McDonnell Douglas .. Aircraft. Aircraft. 1921 in aviation. 1967 in aviation. McDonnell Douglas. McDonnell Douglas. McDonnell Aircraft. McDonnell Aircraft. Douglas Aircraft Company largely operated as a division of McDonnell Douglas -LRB- MD -RRB- after the merger .. Aircraft. Aircraft. McDonnell Douglas. McDonnell Douglas. MD later merged with Boeing in 1997 .. Boeing. Boeing
related.