Revealing mistake: As Harm & Mac are returning to the US, we are told they are flying out of London Heathrow. But the stock footage of an airport used is actually London Gatwick, identified by its distinctive control tower, and not Heathrow.
Revealing mistake: When Harm kills a poacher hunting them, they take his rifle but the ammunition he has for the rifle is shotgun shells.
Revealing mistake: The municipal court-room used for the Chief's arraignment hearing looks amazingly similar to the military court-room at JAG. Or maybe, the same architect of the Navy's court-room was retained by the District as well.
Chosen answer: When landing on an aircraft carrier, a pilot "calls the ball" by confirming to the landing signal officer (LSO) that they have the carrier, and more specifically its landing guidance systems in sight. Carriers use a Fresnel lens system which is a light only visible at a certain angle, so if a pilot sees the "ball" they are at the correct altitude and glide slope for landing.
Sierra1 ★