Lt. Col. 'Bull' Meechum grabs Cpl. Atcherly by the feet and dunks him head first into the toilet. After he pulls him out and lets go of him Atchlerly's shirt is mostly dry. But in the very next shot Atcherly's shirt is almost completely soaked with water.
As the Santini family pulls up to their new home, Lillian is seen putting her arm in the window. In the next shot her arm is no longer in the window.
As Santini's family is waiting at the hangar for him to arrive, Lillian's hair changes. With the wind blowing, sometimes her hair is messed up, sometimes it is combed nicely.
When Ben meets his dad at the officers' club to celebrate Ben's 18th birthday, Bull offers a toast. When he rises to offer the toast, he picks up the beer glass. However, when the camera angle changes, he is now holding the liquor glass and the beer glass is back on the table.
When the Santini family is in their station wagon, in the process of moving, Santini wakes his son up. The pillow that Lillian was using is missing in the shot of the awakened boy and Santini.
In Colonel Hedgepath's office, he admonished, "And don't go attacking anymore corporals on the latrine!" No Marine would refer to a bathroom as a "latrine"; that is an Army term. In the Marine Corps and the Navy, the term is "head."
The squadron that Bull Meechum assumes command of, VMFA-312, was known as "Checkerboards", not "Werewolves". In the opening scene, he dogfights with two navy F-4s while flying a VMFA-312 jet. Supposedly, he left that squadron in Spain! Also, the tail letters for VMFA-312 are "DR", not "DF".
When Bull Meechum is in bed with his wife, his arm bears a tattoo of VMFA-323. This unit was designated VMF(AW)-323 in 1962.
In the night flying scene (which was actually a Day for Night shoot), when Bull lights the afterburners on his F-4, we barely see the afterburner flames inside the engine nozzles. At nighttime, the afterburner flames on an F-4 are visible to at least half the length of the aircraft behind the nozzles and up to over twice the length.
In the opening dogfight sequence you hear the lead pilot call
"Okay, it's Marines verses Navy"; and you see a F-4J Phantom with the word Navy on the side. However, the squadron designation is VMFA-251. At the time, only Marine Phantoms carried the "VMFA" designation, Navy Phantoms were "VF" . The "Marine" squadron was in fact VMFA-251 Thunderbolts, who now fly the F/A-18C.
After Col. Meechum dunks Cpl. Achley's head in the toilet, he tells him to "get out!". The strike plate for the stall door has been visibly loosened, allowing the stall door to swing outward, which it is not intended to do. The prank would be difficult to pull off if the door only swung inward.
The film begins in 1962, but the aircraft are F-4J Phantom II's, a version first produced in 1966. They fill in for the F-4B which reached its first Navy and Marine squadrons in 1961. The aircraft have ECM antennas on the intake shoulders, which were added in 1975. Finally, the planes are gull-gray on the bellies and noses. This was a paint scheme mandated in 1978.
During the last scene of Bull Meechum with his family on the porch prior to the Prom the youngest son is wearing a jacket covered in aviation patches. One of these patches is for the F-14 Tomcat which first flew in 1970 and wasn't operationally deployed until 1974. The film is set in 1962.
Bull Meechum meets his old buddy, Virgil Hedgepath, and they wrestle each other in Hedgepath's office. In the background, you can see a couch. As Hedgepath gets Meechum in an arm lock, on the floor, you can see that the floor has been raised: in the background, the couch is noticeably higher, and you can see the side of the platform that the actors are on, directly below Robert Duvall's face. Filmed in a 4:3 ratio, the raised floor was cropped out for the 1:85 theatrical release.
When Ben misses his first free throw in the second half of the basketball game, the camera cuts to the Eagles cheerleaders. Scaffolding from earlier shots is visible, stored in the entrance area of the gymnasium. The fire code would not permit it there during an actual game, and it does not appear there at any other time.
In the initial mock dogfight, the situation is described as being 1-v-1, but multiple aircraft are seen on both sides.
At a military funeral all personnel in uniform render a hand salute during the playing of Taps. In the movie the only personnel presenting arms are the firing detail.
In the opening mock dogfight, the Phantoms glint in the sunlight. That is the LAST thing a fighter pilot would want. It can be picked up visually by enemy pilots at long distances and is (sometimes literally) a dead giveaway. Fighters are always painted in flat colors (if not in camouflage) with the wings unpolished (no wax job) to subdue their visibility.