Continuity mistake: On the boat after leaving Kilgore Chef lights up a joint and hands it to Lance who holds it between his thumb and index finger. In the next shot it's between his 1st and 2nd fingers as he offers it to the Captain. (00:52:25)
Continuity mistake: On the boat they offer a joint to Captain Willard who approaches them clean-shaven and dry. He wants nothing to do with them and goes back to his work but in the next shot he's dripping wet and needs a shave. (00:52:30)
Audio problem: On the boat after they offer the joint to Captain Willard, Clean says, "All right, that's great" and his lips don't match what he's saying. (00:52:40)
Revealing mistake: After they ditch Kilgore they dock the PBR on the side of the river. The film jumps here as the camera hits a tree branch as it zooms in on them. (00:53:30)
Continuity mistake: They dock the boat on the side of the river and as Lieutenant Kilgore flies over looking for his surfboard we see a long rope running from the front of the boat to a tree. It's in some shots but not in others. (00:53:45)
Continuity mistake: As Colonel Kilgore flies over looking for his surfboard the boat is docked with it's bow towards the shore in some shots and it's stern towards the shore in others. (00:54:10)
Continuity mistake: After Colonel Kilgore's helicopter flies over looking for his surfboard Lance says," Let's get this board out of my turret" but in several shots you can see the surfboard is not in his turret but wedged next to the roof of the boat. (00:54:15)
Visible crew/equipment: In the shot of Captain Willard and Lance joking about the colonel Lance says, "how am I going to shoot him the next time he comes around?". Look closely between the two actors as an equipment shadow moves from left to right than back again against the trees behind them. (00:54:45)
Continuity mistake: Lance wants the surfboard out of his gun turret so Captain Willard pulls it straight up with both hands. In the next shot he's got the surfboard under his arm. (00:54:45)
Continuity mistake: As Chef and Captain Willard continue walking through the jungle looking for mangos Chef says, "Hell, I joined the Navy" and he's holding his gun out in front of him with both hands. In the next shot he's carrying it over his right shoulder. (00:57:00)
Continuity mistake: As Chef and Captain Willard are walking through the jungle looking for mangos Chef says," I was supposed to go to Paris" as he's walking over the roots of a huge tree. He continues talking but in the next shot he's out in the open, nowhere near the roots of that tree. (00:57:00)
Continuity mistake: As Chef and Captain Willard walk through the jungle we get a couple of good close-ups of the band-aid on his cheek and it's different between shots. In the close-up when he first hears the tiger, the right side of the band-aid is pointing towards the top of his ear lobe. Then just seconds before the tiger attacks we see it pointing directly into the middle of his ear. (00:57:50 - 00:58:45)
Continuity mistake: Just before the tiger attacks them there's a close-up of Captain Willard's face with a large leaf in front of him to his right. As the tiger lunges he runs several feet to his left. He gets out of the way by moving, but the next shot as he fires his rifle he's back in the same spot again. (00:58:50)
Continuity mistake: After the tiger attack Chief Phillips backs the boat out away from the shoreline and says, "Clean bring that 60 forward" well after the boat has cleared the tree that has been camouflaging it. In the next shot the tree is hitting Clean in the face. (00:59:20)
Continuity mistake: As Chef and Captain Willard get back on the boat after the tiger attack Clean is on the 60-caliber gun and the entire boat is camouflaged under a tree. Clean says, "Let's go" and you can see the river behind him without the tree there obstructing the view. (00:59:20)
Continuity mistake: Chef says, "I gotta remember, never get out of the boat" as he sits in front of Chief Phillips on the starboard side of the boat. In the next shot as they pull away from the tree they've been hiding under he's walking around on the other side of the boat. (00:59:30)
Continuity mistake: After the tiger attack Chief Phillips asks, "What happened, how many is it?" and Clean is firing the 60-caliber gun behind him at the shoreline. Smoke pours out of the gun as he fires but in the next shot the smoke is not there and the gun has not been fired. (00:59:30)
Continuity mistake: Back on the boat after the tiger attack, Chef freaks out and yells, "Yes I've had it" and the surfboard behind Chief Phillips' head moves about a foot to the left between shots as he says, "Tiger?" (00:59:40)
Continuity mistake: Before he talks to the sergeant about fuel for the boat Captain Willard looks out at the stage were the USO show is going to be held and it's not raining as it was in the previous shot of him walking on the dock. (01:00:50)
Continuity mistake: On the boat Captain Willard reads newspaper clippings about Colonel Kurtz' and thinks to himself, "38 fucking years old." He is sweating profusely, with sweat dripping off of his face and neck. However, his right hand is perfectly dry when he lifts a flashlight and moments later a cigarette. (01:01:00 - 01:02:50)
Chosen answer: Kurtz was protected by political connections and his military record from being relieved of command, and the Montagnard people whose village he was in were considered American allies, so they couldn't just send a force in to kill him or relieve him of command, but an individual assassin. (The US Government's "official" policy is that they do not engage in assassination, which is why "this mission does not exist, nor will it ever exist").
Captain Defenestrator