Revealing mistake: When Indy is running through the cave and finds the spy that took the artifact with spikes through him, he brushes up against the dummy and it shakes like rubber and the light bounces off it like rubber. (00:09:10)
Continuity mistake: At the beginning of the film, When Indy uses the whip to take the guides gun away, Satipo makes a weird face and starts to move away in amazement. The very next frame, in a wider shot, he is not finishing his movements, but on the contrary he is standing still, with a normal gesture, until a second later he starts to repeat the movement and looks from before.
Continuity mistake: When Indy is fighting the Nazis on the truck, one Nazi is thrown from the truck and is rolling the opposite direction of the truck. (01:23:30)
Factual error: During the travel to Nepal, "Thailand" is written on the map. The country has had this name only since 1939. This film takes place in 1936, when Thailand was called Siam. (00:23:20)
Continuity mistake: After Satipo runs with the idol, Indy grabs a root to help him climb up the ledge. Half a second later, from a different angle, the root is meters away and he is grabbing it again, repeating the whole scene.
Continuity mistake: Just before the car carrying Marion in the wicker basket explodes in the alley, Indiana shoots a man twice in the chest. The man has blood stains on his shirt before he is shot.
Continuity mistake: As Indy and Marion are starting to run from the plane, you can see the yellow wheel chocks are back in place under the plane's tires.
Continuity mistake: After Indy steals the idol, while he is hanging in the well, in the front angle his left leg is bent and already outside, in a quite comfortable and secure position; yet in the angles from behind both legs are inside, hanging loose.
Continuity mistake: After hitting one thug, Indy jumps out of the way of one trying to spear him, leading to the one behind Indy getting run through. As the guy gets run through, he is in front of a hanging string of fruit, with the stacked fruit to his right. After a cut scene to Indy and Marion running away, the run through thug is now facing the fruit stand, setting up the sight gag of the blade sticking out with two fruits stuck on it.
Continuity mistake: While Indy is in the Well of Souls, Belloq greets him and is standing by one of the four sides of the rectangular hole. A frame later he stands by one of the corners.
Continuity mistake: After grabbing the idol, the cave starts to collapse, filling the place with rocks and rubble. When Indy starts to run, from the angle behind the floor is clean, rocks starting to fall for the first time.
Continuity mistake: Satipo drops the whip half a meter away from the closing gate, then runs away. However, when Indy rolls underneath the door, the whip is laying right next to it.
Continuity mistake: When Indiana is hiding his face with the cloth, watch as he enters the tent that Marion is being held prisoner in - at first, Indiana has to hold it in place; in the next shot, he has it tucked into the rest of the folds. The next shot, the actual position of the cloth changes.
Factual error: At the beginning of the movie, Indy escapes in biplane with registration OB-CPO (a Star Wars nod, as noted in trivia). However the OB registration is used by Peru, and it should be followed by four digits, not by three letters. (00:12:10)
Revealing mistake: The Pan American aeroplane Indiana Jones boards in San Fransisco looks similar to (but has noticeable differences from) the Boeing 314 PanAm used for transpacific flights. This aeroplane did however not fly until 1938 and at the time of the story the company only flew transpacific with Sikorsky S-42s, an aeroplane with a completely different body than the one used in the scene.
Revealing mistake: When Indy is fighting the big German at the base of the airplane, Indy reaches down and grabs a handful of sand to throw in his face. You can see the finger marks in the sand from a previous take.
Audio problem: When Marion meets up with Indy on the steps of the building at the very end of the film, she asks what was going on in there. Her first few lines of dialogue were dubbed in after shooting. Her mouth isn't moving with the dialogue.
Continuity mistake: When Indiana is fighting the Big German mechanic by the plane, the plane goes around in circles and the wing tip of the plane punctures a hole in a petrol tanker that is parked near by. This causes the petrol to gush out of the tanker and you can see that ground underneath the plane gets totally drenched with petrol. But in the later shots, the ground under the plane is dry. There is also a shot where you can see the tanker in the background not pouring petrol any more and all you can see is a little wet spot around the tanker. (01:18:45)
Revealing mistake: During the truck chase scene, Indiana is thrown or forced over the front of the bonnet and almost run over. There is a wide camera shot, and while holding on to the front fender, Indiana can be seen sitting on a chair which is attached to the truck. (01:27:40)
Revealing mistake: When we have the exterior shot of the ship that Harrison Ford, Karen Allen, and the ark are aboard, even on the DVD can be seen specks of dirt over the view of the ship and the ocean - obviously it was filmed through the window of another ship. (01:31:35)
Answer: The scene you describe was indeed filmed. It was cut out of the US release of the film although I cannot speak for the Australian version. The scene also appears in the Marvel Comics adaptation. http://www.theraider.net/films/raiders/deleted_scenes.php has a list of this and the other deleted scenes.
Phil C.