Sino – Vietnamese clashes in the air

Gentlemen I know that there is already a thread for the Sino – Vietnamese war and I had some doubts if creating a new one would be appropriate but I came to the conclusion that the matter proposed for discussion warrants that (I seriously hope mods / admin concur). I am speaking about Sino – Viet clashes in the air and that includes by extension air defences. Now I know about the fact, that both sides used transport aircraft & helicopters for supplies / logistics and the like but I would prefer to leave it for later. Now I propose to discuss actual air combat / shoot downs by AD (including engagements which did not result in a “kill”). Before presenting a short list and asking for more details & other incidents let me point out, that there is a well known pic of a PLAAF J 6 with its nose section missing being guarded by Vietnamese militiamen (the said pic is even floating around somewhere on this forum if I am not mistaken). However this is not an example of Sino – Vietnamese air combat / AD action for the J 6 was shot down by Chinese AD as it was attempting to defect and came down in Viet territory. This is a subject for a separate discussion. Now as for those Sino – Viet action in the air. The first resulting in a “kill” would be on before the 1979 war but close enough. In August 1978 (the exact date would be appreciated) a Chinese aircraft was shot down over Xuan Thuy in the Nam Dinh province by Vietnamese fighter jets. This event was supposing witnessed by many people from the ground. The Chinese aircraft came down in Viet territory with both the wreckage and the body of the pilot who was KIA being recovered (his remains were subsequently returned to China) while the wreckage of the aircraft were put on public display in Nam Dinh – pics would be most welcomed as they were surely made and for 99 % published and I guess Vietnamese forum members could dig them up though I am fully aware that it would require some serious and time consuming research effort with possibly tons of old newspapers to be sifted through. The Chinese came close to scoring even in 1986 (exact date would be most welcomed) when two J 6 intercepted a Vietnamese MiG 21 which intruded into PRC airspace. The lead J 6 launched PL 2 air to air missiles but they failed to hit and the Viet aircraft managed to escape. But the next year the Chinese scored although it was a “kill” performed by their AD. Namely in August 1987 the PLAAF 97 Battalion shot down (I suppose using a Chinese SA 2 “clone”) a Viet MiG 21. Near Long Zhou Gunagxi province. The pilot Capt. Chen Zun was captured. More details, pics etc. regarding those incidents would be most welcomed I think not only be me but also by virtually anybody with interest in Chinese and Vietnamese military history.