When Harm and Bud drive up to the Douglas home (seeking the pilot's wife and family) there are several sets of damp tyre tracks on the road from the puddle in the gutter at the end of the driveway. This implies recent visits to the house (where the family have, in fact, been missing for days. This often happens in USA-made TV, where several "takes" (especially those action scenes involving "stunt" driving or skids) usually result in multiple skid-marks on the road, within one to three feet of the path taken by the vehicle in the final version of the take.
When Harm and Bud are waiting for the UFO photographer Harm says the man is late, he was supposed to meet them at 11:00 PM but hadn't shown by 11:50 PM. However the episode's title screen stated the time as 0450 Zulu, Zulu time is four hours head of Eastern Standard Time, so if it were 0450 Zulu the local time would be 12:50 AM.
Naval ships do not use their names over the radios. They all have call signs. The Coral Sea's call sign was Mustang.
The commanding officer of the supposed USS Coral Sea (CV-43), an aircraft carrier, wears not gold wings but rather the surface-warfare insignia, whereas in the real world of the US Navy the CO of an aircraft carrier is a Naval aviator, not a surface skimmer. The CO also does not wear a command-at-sea pin on his khaki shirt.
Harm asks to have a call put through to Major MacKenzie about USS Coral Sea(CV-43). Screen flashes to the superstructure of USS Enterprise(CVN-65).
Later planes are supposedly launched from USS Coral Sea(CV-43), as planes clear the catapults, the ship number on the bow is either 66 or 68 indicating those planes launched from USS America(CV-66) or USS Nimitz(CVN-68)
USS Coral Sea (CV-43) was decommissioned 30 Apr 1990, 7-1/2 years before this episode aired on 28 Oct 1997.
In at least one sequence the sound of piston engines accompanies an E-2 Hawkeye search aircraft in flight. Although the Hawkeye is propeller-driven, the powerplants are turboprops rather than reciprocating engines. The turbine engines emit distinctly different sounds.
Despite the house supposedly being empty someone can be seen walking behind Bud and Harm at 30:20.