Indy and Sala take the headpiece to the staff of Ra to a translator. They ask him if the headpiece says anything about how long the staff should be. On one side the translator says the staff should be six ka-dong (sp) in length; which Sala translates as "about 72 inches." Divide 72 by six, that means a ka-dong is about 12 inches (one foot) in length. Then the translator flips the headpiece over and says "subtract one ka-dong to honor the Hebrew God for whom..." Which means that the total length of the staff should be 5 ka-dong or 5 feet. When Indy takes the staff into the map room, it is at least his height, and I'm pretty sure Harrison Ford is more than 5 feet tall.