Revealing mistake: When Harm kills a poacher hunting them, they take his rifle but the ammunition he has for the rifle is shotgun shells.
Factual error: This episode begins with a luxury cruiser being pursued by a USN Oliver Hazard Perry class frigate. In order to convince the vessel to heave to, the skipper of the USN ship orders two warning shots to be fired from the frigates forward gun. Oliver Hazard Perry class frigates do not have a forward gun. They have a launcher, which is visible in the ships external shots. The shot of the 5" gun firing is archive footage of a completely different (and much larger) vessel.
Revealing mistake: The cockpit of the C130 is not correctly rebuilt. The pilots are sitting too close to each other. (Verified by a former C130 pilot with the USMC.)
Death Watch - S3-E19
Continuity mistake: At Harm's apartment, when talking to Mac about Cmdr. Krennick's advances towards him, he tells Mac that he wouldn't get involved with a superior officer, anymore than she would. However, it had already been established earlier this season in "For The Good of the Service" that Mac had a romantic relation with her Commanding Officer, Lt. Colonel Farrow.
In Thin Air - S8-E5
Continuity mistake: After Rabb flies as RIO near the end of the movie, they land in a F-14 with the number 114, however when they get out of the aircraft the number is 242.
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.
Continuity mistake: When Rabb takes off with the F-117 in the Iranian desert we see bushes when he lifts off, however in the next shot, when we see the Nighthawk from the front, the bushes are gone.
Factual error: The attention to detail on the ship was excellent, except that the sailors' teeth looked too good considering that sailors in the 19th did not brush their teeth and often chew tobacco.
Deliberate mistake: During the civilian sheriff's pursuit of the Navy car, the sheriff is occasionally visible in the passenger seat of his patrol car instead of the driver's seat.
Deliberate mistake: Because the series changed networks after the end of season one, this episode completely ignores that season's cliffhanger about Harm being arrested as a suspect in the murder of Lt. Schonke.
Continuity mistake: The hull number on the flight deck "74" didn't match the hull number on the sailors caps. "74" is the hull number of the Nimitz class carrier USS John C. Stennis.
In Thin Air - S8-E5
Continuity mistake: When Harm goes up with Lt. Albrecht as his RIO, they are shown flying 4 different aircraft - Tomcats 103, 104, 114, 242. This is what happens when stock footage is used.
Factual error: In this episode there is continual reference to the seahawk helicopter in the hanger. The helo that is pictured in the episode is a lot bigger than a seahawk and resembles a sea king. Oliver Hazard Perry class frigates can hold two seahawks but no Sea Kings.
Continuity mistake: When Harm is ejected from the jeep after the mine explosion, his hat is on his head after he lands, but in the next scene, it shows his hat situated on the ground between the jeep & him.
The Bridge at Kang So Ri - S5-E18
Continuity mistake: When Harm is landing the plane, there is a shot of his hand on the controls, but it is minus his school ring which was there in the previous shots.
Factual error: The scene outside the gate of the Naval Amphibious Base - Little Creek was NOT the same as the actual gate. Little Creek does not have palm trees adjoining it. The base itself is located at Norfolk, VA.
The Witches of Gulfport - S5-E21
Continuity mistake: While Mac is in a restaurant with three of the Wiccans, another woman comes over to give them verbal abuse. When you first see her, part of her dress is showing. When the camera comes back to her, that part is no longer seen. Also, the exterior scenes indicate that the location really isn't Gulfport.
King of the Greenie Board (1) - S5-E1
Continuity mistake: When Harm deals with the Lear Jet, his F-14's registration number keep changing with each different shot of it.
Adrift (1) - S6-E24
Continuity mistake: The USS Patrick Henry in "JAG" has always used the hull number "74" on the sailors' ballcaps, as well as the scenes of the ship. (CVN-74 in real-life is the USS John C. Stennis). However, in the scene just before the pilots' briefing, the stock footage of the carrier was of a different vessel, hull number 59. In real-life, "59" was the USS Forrestal (CVA-59), the ship that had one of the deadliest shipboard fire on July 29, 1967. The fire killed 132 crewmen, injured 62, with 2 missing & presumed dead. The fire raged for several hours & would have destroyed the carrier, if not for the actions of the heroic crewmen to save her.
Revealing mistake: When Harm talks to the young sailor about the lighter and how high the flame really was...he says "dial that up as high as it'll go"...keep your eye on his collar, and you'll see the tag on his shirt says "DAVID"...