Need to Know - S8-E7
Factual error: Those that have a technical background may have noticed at the end, when the sub was destroyed due to being crushed from the water pressure, it was shown as having EXPLODED, instead of IMPLODING. This was due to the cost of setting up a shot, when stock footage was already available.
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 ★