Then I sat down with Francis [Ford Coppola] to talk about the beginning. And the script at the beginning of the film had long ago been tossed away because Francis wanted the film to have essentially a prologue to set up the parameters and the themes in a kind of symbolic way of things that you would encounter later on and to establish the character and dilemma of this Captain Willard, played by Martin Sheen. The two pillars on which the opening of the film was now going to be built were two shots that were never intended to be in the film in the first place. One of which was a slow motion shot of a napalm explosion that was shot by a sixth camera. When an explosion went off, you had as many cameras shooting it as possible, because at that time it was the biggest explosion ever staged for a film. In fact, it probably still is the biggest, because now you would do that explosion digitally. You wouldn't have an actual gigantic explosion such as that. So, photograph it with as many cameras as possible because it's only going to happen once and you want to make sure you get the correct coverage.
A.D. Flowers, the man who was responsible for the physical special effects during the shooting, of course, knew how big this explosion was going to be, and he wanted a record of it for his own purposes. So the sixth camera was set at super slow motion, I think probably 240 frames a second, certainly well over 100, maybe 160. And this shot, of course because it was slow motion, there was never a place for it in the actual story of the film, so it was set aside. Oh, that was A.D. Flowers' shot.
At one point in the Philippines, Francis was in the editing room, and his restless mind went and looked at that; what's this? He picked it up. 'Oh, that's this slow motion shot', in which Francis has never seen. 'Well, let me see it.' And so he looked at it, and the lightbulb went off and he thought, this is how I want to begin the film. This telephoto shot of the jungle. Just these flat trees shot from very far away but with a very telescopic lens and then poof, suddenly it bursting into flames with these strange slow motion helicopters sort of floating in at various tilted angles going through the frame.