Revealing: After crashing in the jungle, while hanging "upside down,"  Mel Gibson's medallion hangs in the wrong direction. This shows that the actors were actually right side up, and the camera was inverted in order to create this scene.

Other: When Robert Downey Jr. lowers the helicopter onto the freeway to yell at the truck driver, he is very close to the truck driver, so close that the truck driver can even hit the helicopter. Why does a long haired man standing underneath a helicopter not have his hair blown around?