Were you watching? Later the Next clue is at the Hanoi 52 Memorial, shot down during the war.
B-52 lake or May Bay B52 is located just south of the West Lake along Hoang Hoa Tham Rd, more a rather large pond it contains wreckage of a B-52 Stratofortress shot down on 19 December 1972 during Operation Linebacker II
http://en.wikipedia.org/wiki/Operation_Linebacker_II
http://en.wikipedia.org/wiki/File:B-52_shotdown_piece.jpg