'Xian H-6, surely?'
Sorry. Xian makes aeroplanes, Harbin makes beer. Easy mistake to make!
Actually, when the TU16 was first made in China under licence, it was at the Harbin aircraft factory. Production was later transferred to the Xian factory, but the designator H6 was retained - the H referring to Harbin. If it had first been produced at Xian, it would have a J designator such as the Xian J7 (MiG 21 copy). The J comes from the original Wade-Giles spelling of the city of Xian, which has it as Jian. Both are pronounced the same.
I'll get me anorak!