Continuity mistake: As they begin to break out of the fog bank Chief Phillips says, "Lance on the 50s". Lance doesn't move from where he is on the roof of the boat but Chef goes to the machine gun twice between shots and points it in different directions each time. (02:21:00)
Continuity mistake: Clean hammers on the helicopter door and says, "I got my rights, man." He's in direct sunlight when you see him from inside the helicopter and not in the shot of him on the outside. (01:30:00)
Continuity mistake: When Colonel Kurtz says, "And they call me an assassin," the statue in front of the TV casts its shadow on the left of the picture tube. The lighting doesn't change throughout this scene but the next time we see it the shadow is one quarter of the way to the center of the picture tube. Later the shadow moves back to the side of the TV again. (00:13:55)
Continuity mistake: After leaving the Do Lung Bridge everyone sits around reading their mail from home. Lance takes the canister of purple smoke and proceeds to throw it overboard as he says, "Hot potato. Hot potato." In the next shot he has the canister in his hand again. (01:51:15)
Continuity mistake: There's a shot of two injured soldiers in wheelchairs sitting front row dead center as playmate of the year Carrie Foster is brought out to the audience. There's another soldier crouching between them who disappear between shots. (01:07:50)
Continuity mistake: While discussing surfing at the beach party Colonel Kilgore says, "We'll pick your boat up and put it down like a baby where you want it." The cigarette he's smoking here gets longer between shots. (00:33:35)
Continuity mistake: When the soldiers lower Clean's body into the grave they're all standing. In the next shot they're all crouching. (02:01:50)
Factual error: The date on the top of Chef's letter from Eva says, "Sept" with the year conveniently whited out. If the letter was written in September of 1969 she couldn't have known about Manson who wasn't arrested until December 3, 1969. This also dates the movie as taking place sometime in 1970. (01:50:50)
Continuity mistake: In the first close-up shot of the soldier wounded in the Vin Din Dop courtyard there are two medics working on him. In the next shot there is a third kneeling by his left leg in the exact spot where the cameraman just stood in the previous shot. (00:43:20)
Continuity mistake: The day after the USO Playboy Bunny show, the patrol boat canopy is set afire by some pranksters from a passing boat. Yet, that night in the scene at the Do Lung Bridge, the canopy is intact. It goes through some amazing transformations during the remainder of the picture. (01:41:33)
Continuity mistake: Hubert de Marais continues to speak to Roxanne in French. As she looks at him intently her expression changes and she goes from having her hands at her sides to unfolding her napkin again between shots. (02:04:30)
Continuity mistake: As they begin to break out of the fog bank Chef says, "watch it over here, chief, got a stump". Here he's helping Chief Phillips steer the boat with a long pole that he places back on the floor of the boat after the uses it. You can see that it's not hanging over the right side of the boat behind Chief Philips but at the beginning of the arrow attack it's back extending out over the side. Then a few shots later as Captain Willard runs to the back of the boat to stop Chef from firing it's gone completely. (02:20:55)
Continuity mistake: Colonel Kurtz drops Chef's head into Captain Willard's lap. At first the head has no blood on it but in the next shot when the captain realizes what it is Chef's face has blood all over it. (02:47:10)
Continuity mistake: Hubert de Marais says to the Captain, "because life, sometimes is very cruel, as you can see" as he hands him a plaque. At first he's holding it with his left hand then when he gives it to him, he's using both hands. (02:03:15)
Continuity mistake: As captain Willard, Lance, and Chef stand on the dock they hear the voice of a Frenchmen shouting at them. If you look closely at Chief Phillips on the bridge of the boat, he doesn't have a rifle in his hands but in the next shot he does. (01:57:20)
Visible crew/equipment: On the boat while reading Kurtz' file Captain Willard recalls Harrison Ford saying, "and follow every order, however ridiculous" while having lunch with the general earlier in the movie. If you look at the close-up of his eye you can see a cameraman and another person's reflection as they stand in front of him. (01:18:35)
Continuity mistake: A guy from Lazaro's boat throws a smoke canister that catches fire on the roof and Chef tries to put it out with a fire extinguisher. When we first see him trying to put the fire out his shirt is dry then the next time we see him his shirt is full of sweat. (01:16:40)
Continuity mistake: The camera pans left as Colonel Kilgore has a beach party for the men at the end of the day. If you look closely at Lance he has two cans of the beer to the left of him, a Schlitz and a Budweiser. In the next shot the cans are reversed. (00:31:40)
Continuity mistake: As he spots the sampan Chief Phillips says, " Clean get on that 60" and the machine gun on the back of the PBR is aiming left towards the shore. In the next shot "Canned Heat" is pointing directly behind the boat. (01:34:25)
Continuity mistake: Captain Willard and his two escorts get out of a helicopter and walk up to the guard post on the way to see General Corman. The soldier in the front is carrying some yellow papers in his right hand. In the next shot as they pass the guard the papers are in his left hand. (00:09:40)
Answer: It should be noted that "transmutation" is a word Coppola has used to describe the film making process. Https://m.youtube.com/watch?v=LFTQcwgq4CY.
Bishop73