Factual error: In the scene where Rambo plays possum then suddenly takes out the Russian Officer's Hind Helicopter he uses an M72A2 light anti-tank weapon (LAW). When fired, the M72A2 has a back blast that can kill out to 100 feet, which means he would have either blown up his own helicopter or killed all the MIA's he had rescued...

Other: In a scene towards the end, we see a crowd of Vietnamese on a riverbank firing their machine guns into the trees...one soldier clearly walks directly in front of another soldier who continues firing away without hitting him.

Continuity: When Rambo fires the rocket launcher at the Russian Hind helicopter, he is clearly seen aiming a LAW rocket launcher. The LAW is fired by pressing a lever on the top. But when Rambo fires, a quick edit from a previous shot (on the patrol boat) shows him pulling a trigger from the Russian RPG launcher he used to dispatch the Vietnamese patrolboat earlier in the film. The film returns to show him holding the LAW rocket launcher again.